2007-04_NHT_Reformer_LOPA

Layer of Protection Analysis NHT Reformer Unit TOTAL Petrochemicals USA, Inc. Port Arthur Facility October 2008 Project No. 07-099

R R S ENGINEERING 6455 South Shore Blvd., Suite 400 League City, Texas TEL 281.334.4220 www.rrseng.com

77573 FAX 281.334.5809

TOTAL Petrochemicals Port Arthur Refinery

NHT Reformer Unit Layer of Protection Analysis

DISCLAIMER RELATING TO THIS REPORT The work was prepared by Risk, Reliability, and Safety Engineering, LLC (RRS) at the request of TOTAL Petrochemicals. As a material part of RRS agreeing to perform the work for Client, Client has agreed to the terms of this disclaimer. Specifically, Client agrees that, to the maximum extent allowable by applicable law, neither RRS, its employees, agents, representatives, successors, assigns, affiliates, directors, officers, and members, nor any person acting on RRS' behalf in furtherance of its activities in performing the work for Client: 1.

Makes any warranty or representation, express or implied, (all of which are hereby expressly disclaimed) with respect to the accuracy, completeness, or usefulness of the information contained herein or the work, or that the use of any information, method, apparatus, or process contained herein, does not infringe on any rights of others; nor

2.

Will have any liability arising by, through, or under Client with respect to the use of, or for special, incidental, or consequential damages related to or arising directly or indirectly out of the use of any information, method, apparatus, or process disclosed herein or the work; nor

3.

Assumes any liability to client or any third party, with respect to the use of any information, method, apparatus, or process disclosed herein or in the work.

Client agrees that RRS has made reasonable efforts to perform the Work contained herein in a manner consistent with high professional standards. However, Client agrees that the Work was conducted on the basis of information made available to RRS by Client and is dependent on the accuracy of the information provided. Client agrees that all observations, conclusions and recommendations contained herein are relevant only to this work, and will not be applied to any other facility or operation. Client agrees that the Work RRS performed is advisory in nature only and that the responsibility for use and implementation of conclusions and recommendations contained herein rests entirely with Client. Client agrees that it will independently evaluate any actions taken to address the results of this effort to ensure they will not create unacceptable hazards and that safe practices are followed when any change is implemented. Furthermore Client agrees that federal and state regulations are subject to interpretations and no one can guarantee how they will be interpreted in the future. Client agrees that RRS will have no liability for any incident or regulatory action that occurs at Client. Client agrees that it will be solely responsible for disclosure of the Work to any third-party or the use of the work, or any information or conclusions contained therein.

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NHT Reformer Unit Layer of Protection Analysis

TABLE OF CONTENTS PAGE 1.0

2.0

INTRODUCTION............................................................................................................................... 1 1.1

Study Team ..................................................................................................................... 1

1.2

Study Dates ..................................................................................................................... 2

LOPA METHODOLOGY .................................................................................................................. 2 2.1

Scenario Identification ..................................................................................................... 4

2.2

Consequence Severity Evaluation.................................................................................. 4

2.3

Initiating Cause Likelihood Evaluation ............................................................................ 5

2.4

Independent Protection Layers (IPL) Evaluation............................................................ 7

2.5

Rules for Independent Protection Layers (IPLs) .......................................................... 10 2.5.1 2.5.2 2.5.3 2.5.4 2.5.5

2.6

Vulnerability Factors ...................................................................................................... 12 2.6.1 2.6.2

2.7

Intermittent Hazard (Not Always Present) .................................................... 10 Mechanical Relief Devices – Relief Valves .................................................. 10 Check Valves ................................................................................................. 11 BPCS ............................................................................................................. 11 Operator Response to Alarm ........................................................................ 11

Ignition Probability ......................................................................................... 12 Person Present .............................................................................................. 12

LOPA Calculation .......................................................................................................... 12

3.0

SIS EVALUATION ......................................................................................................................... 13

4.0

RECOMMENDATIONS.................................................................................................................... 15

5.0

LOPA WORKSHEETS .................................................................................................................. 18

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LIST OF TABLES PAGE Table 1.

Study Team ..................................................................................................................... 1

Table 2.

Review Team................................................................................................................... 2

Table 3.

Hazard Scenario Target Frequencies............................................................................. 4

Table 4.

Initiating Causes & Likelihood (ICLs) of Failure ............................................................. 6

Table 5.

Examples of Safeguards Not Usually Considered IPLs ................................................ 8

Table 6.

Probability of Failure on Demand (PFD) for Independent Protection Layers (IPLs) .... 9

Table 7.

Integrity Levels (SILs) for a Safety Instrumented System (SIS) ..................................13

Table 8.

Safety Integrity Level (SIL) Determination ....................................................................13

Table 9.

Recommendations ........................................................................................................16

LIST OF FIGURES PAGE Figure 1.

LOPA Flowchart .............................................................................................................. 3

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NHT Reformer Unit Layer of Protection Analysis

LAYER OF PROTECTION ANALYSIS NHT REFORMER UNIT PORT ARTHUR REFINERY TOTAL PETROCHEMICALS

1.0

INTRODUCTION

TOTAL Petrochemicals contracted Risk, Reliability and Safety Engineering, LLC (RRS) to conduct a Layer of Protection Analysis (LOPA) of the NHT Reformer Unit at TOTAL Petrochemicals Port Arthur Refinery. The LOPA methodology used is defined in the TOTAL Petrochemical LOPA Procedure 14 and follows the guidance in the Center for Chemical Process Safety (CCPS) book, Layer of Protection Analysis, 1995. The methodology used in this study meets the requirements of ANSI/ISA S84.00.01, Functional Safety: Safety Instrumented Systems for the Process Industry. The objectives of the LOPA study were to:

1.1

•

Review the HAZOP to determine if the safeguards identified were adequate

•

Determine the Safety Integrity Level (SIL) for the Safety Instrumented Systems (SIS) at the plant

Study Team

The LOPA Study Team is identified in Table 1. Table 1. Name

Study Team

Company

Job Title

Norman Borne

TOTAL Petrochemicals USA, Inc.

Instrument Supervisor

Richard Loupe

TOTAL Petrochemicals USA, Inc.

NAC Operator

Douglas Dornier

TOTAL Petrochemicals USA, Inc.

Process Engineer

Ryan Riffer

TOTAL Petrochemicals USA, Inc.

Ops Superintendent

Roger Allison

Olson Engineering

Instrument Reliability

Allen Runte

TOTAL Petrochemicals USA, Inc.

EE & Systems Supervisor

Geoffrey Kret

TOTAL Petrochemicals USA, Inc.

Rotating Equipment Engineer

David Montondon

Gulfcon, Inc.

Systems Group

John Darwin

TOTAL Petrochemicals USA, Inc.

Systems Group

Sheng-Yen Fletcher

TOTAL Petrochemicals USA, Inc.

PSI/PHA Coordination

Danny Roy

TOTAL Petrochemicals USA, Inc.

Corrosion Specialist

Dennis Ferrell

Olson Engineering

Fac. Dev. E&I

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NHT Reformer Unit Layer of Protection Analysis

Name

Company

Job Title

Paul Pardaen

TOTAL Petrochemicals USA, Inc.

Process Sup. Engineer

Dwayne Austin

TOTAL Petrochemicals USA, Inc.

Systems Group

Rich Hudgins

TOTAL Petrochemicals USA, Inc.

Systems Group

John Pruitt

RRS Engineering

Facilitator

John Alderman

RRS Engineering

Facilitator

Cassie Slough

RRS Engineering

Scribe

1.2

Study Dates

The LOPA was conducted onsite at the TOTAL Petrochemicals Port Arthur Refinery on May 3, 2007. An additional meeting was held on June 21, 2007 to re-evaluate SIL, EIL, and CIL rankings. A review team was assembled to revisit LOPA scenarios, including 39.1, 72.2, 72.9, and 73.8. The review team determined that the commercial severity for these scenarios should be reduced from catastrophic to major. The review team is identified in Table 2. Table 2.

Review Team

Name

2.0

Job Title

Ed Bergmann

HSEQ

Shen-Yen Fletcher

HSEQ

Kelly Nite

Operations

Ryan Riffer

Operations

Geoff Kret

Reliability

Dwayne Austin

Systems

John Darwin

Systems

Clint Gibbs

Systems

Rich Hudgins

Systems

Allen Runte

Systems

David Montondon

Systems

LOPA METHODOLOGY

A Layer of Protection Analysis (LOPA) is a semi-quantitative risk assessment methodology. Put simply, the method consists of assigning a target frequency based on consequence severity and comparing it to a simplified prediction of the actual scenario frequency. The method is based on the AIChE CCPS Concept Book, Layer of Protection Analysis. The steps in the LOPA process are defined in TOTAL Petrochemical Safety Procedure shown in Figure 1.

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NHT Reformer Unit Layer of Protection Analysis

Figure 1.

RRS Engineering, LLC October 31, 2008

LOPA Flowchart

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2.1

NHT Reformer Unit Layer of Protection Analysis

Scenario Identification

The Study Team began by identifying scenarios of concern based on results from the previous PHA. For an existing PHA, only those scenarios with a shutdown system were reviewed. In some cases, further definition of the consequence was required. In a LOPA, a scenario is an initiating cause, a description of the consequence (assuming all safeguards fail), and a list of all protection layers in place to prevent the consequence from occurring. The LOPA consists of assigning numerical frequency numbers to the initiating cause and each protection layer, then determining if protection layers in place are adequate. Additionally, scenarios were added based on shutdowns in the cause and effect charts. Some scenarios were reviewed and identified as a moderate severity. Since these scenarios were considered a moderate severity, they did not meet the criteria for using LOPA. These scenarios are contained in Appendix A. Note: A scenario has only one cause and only one consequence. If multiple causes for the same consequence are identified in the PHAs, then each cause was analyzed separately using LOPA. 2.2

Consequence Severity Evaluation

The Study Team assigned a severity ranking to the consequences. Each consequence severity was also assigned a Targeted Frequency (TF) based on Table 3. Table 3. Severity Level Moderate

Hazard Scenario Target Frequencies

Safety

Environmental

Commercial

Not required to conduct LOPA

Onsite: -

Recordable, TRIR

-

Medical treatment

Target Frequency (1/Yr)

Offsite: Serious

No effect

Onsite: -

Permanent injury

-

Lost time accident

Recordable environmental event

< $2,000,000

Not required to conduct LOPA

Offsite: -

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No permanent effects

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TOTAL Petrochemicals Port Arthur Refinery Severity Level Major

NHT Reformer Unit Layer of Protection Analysis Safety

Onsite: -

Lethal effect on 1 person

-

Multiple recordable injuries

Environmental

Commercial

Target Frequency (1/Yr)

Reportable environmental event

$2,000,000$10,000,000

10-4

Reportable environmental event with offsite impact

$10,000,000 $100,000,000

10-5

> 100,000,000

10-6

Offsite: Catastrophic

Shelter in place

Onsite: -

Multiple fatalities

Offsite: Disastrous

Recordable injuries

Onsite: -

Multiple fatalities

Offsite: -

2.3

Multiple fatalities

Initiating Cause Likelihood Evaluation

The Study Team assigned an Initiating Cause Likelihood (ICL) based on the numerical values defined in Table 4. These values are based on industry consensus as presented in the CCPS Concept Book on LOPA. The CCPS Concept Book provides the following guidance on causes: •

Control loop failure - includes all components of the control loop, as well as the possibility that the control loop could be set in error to a dangerous state by the operator

•

Routine human error - includes a task in the field or at the operator console that is performed on a routine basis by the operator and that, if done improperly, could result in the process deviation under review

•

Non-routine human error - tasks that are not done on a routine basis but are possible actions by an operator for some event, such as startup or shutdown that, if done improperly, could result in the process deviation under review

•

Pumps and other rotating equipment - includes any piece of equipment with normal moving parts

•

Fixed equipment - involves failures in non-moving equipment that would lead to the process condition under review; for example, tube failure on a high-pressure steam exchanger leading to high process pressure

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NHT Reformer Unit Layer of Protection Analysis

Table 4.

Initiating Causes & Likelihood (ICLs) of Failure

Initiating Cause (IC)

Initiating Cause Likelihood (ICL) (events per year)

BPCS instrument loop failure

1 x 10-1

Regulator failure

1 x 10-1

Fixed equipment failure (exchanger tube failure, etc.)

1 x 10-2

Pumps and other rotating equipment failure

1 x 10-1

Cooling water failure (redundant CW pumps, diverse drivers, etc.)

1 x 10-1

Loss of power (redundant power supplies)

1 x 10-1

Human error - (routine task, once-per-day opportunity)

1 x 100

Human error - (routine task, once-per-month opportunity)

1 x 10-1

Human error - (non-routine task, low stress)

1 x 10-1

Human error - (non-routine task, high stress)

1 x 100

Gasket / packing blowout

1 x 10-2

Turbine / diesel engine over speed with casing breach

1 x 10-4

Third party intervention (external impact by backhoe, vehicle, etc.)

1 x 10-2

Crane load drop

1 x 10-4 per lift

Lightning strike

1 x 10-3

Safety valve opens spuriously

1 x 10-2

Pump seal failure

1 x 10-1

Unloading / loading hose failure

1 x 10-1

Misalignment of car sealed or locked valve where there is a regular check of the alignment of the valves

1 x 10-2 per opportunity

LOTO (lock-out tag-out) procedure failure, e.g., overall failure of a multiple-element process

1 x 10-3 per opportunity

Operator failure to execute routine procedure, assuming well trained, unstressed, not fatigued

1 x 10-2 per opportunity

Other initiating events

Develop using experience of personnel

Source: Table 5.1, p 71 of the 2001 CCPS Concept Book “Layers of Protection Analysis”.

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2.4

NHT Reformer Unit Layer of Protection Analysis

Independent Protection Layers (IPL) Evaluation

The defining characteristic of a protection layer is that it prevents the consequence from happening. Each IPL must function such that the defined consequence will not occur. Each protection layer counted must be independent of other protection layers. That is, there must be no failure that can deactivate two or more protection layers. If a protection layer is believed to be more reliable (a lower value for Probability of Failure on Demand - PFD), a quantitative method should be used to confirm the PFD. For example, if the team desires to improve the unavailability of risk reduction logic in the Basic Process Control System (BPCS) by adding additional sensors or final elements, the impact event should be reviewed by a quantitative method such as fault tree. The protection layer is: •

Specifically designed to prevent or mitigate consequences of a potentially hazardous event

•

Dependable and can be counted on to do what it was intended to do

•

Auditable and a system to audit and maintain it

The Study Team identified which protection layers meet the definition of IPLs as given in this section. This is often the most difficult part of LOPA. Table 5 contains safeguards that are not typically given credit as IPLs.

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Table 5.

NHT Reformer Unit Layer of Protection Analysis

Examples of Safeguards Not Usually Considered IPLs

Safeguards Not Usually Considered IPLs

Comments

Training and Certification

May be considered in assessing the PFD for operator action, but are not, of themselves, IPLs

Procedures

May be considered in assessing the PFD for operator action, but are not, of themselves, IPLs

Normal Testing and Inspection

Assumed to be in place for all hazard evaluations and form the basis for judgment to determine IPLs and PFDs; normal testing and inspection affects the PFD of certain IPLs, thus, lengthening testing and inspection intervals may increase the PFD of an IPL

Maintenance

Assumed to be in place for all hazard evaluations and forms the basis for judgment to determine the PFDs of IPLs.

Communications

Basic assumption that adequate communication exists in a facility; poor communications affects the PFD of certain IPLs

Signs

Signs, by themselves, are not IPLs; signs may be unclear, obscured, ignored, etc. and may affect the PFD of certain IPLs

Fire Protection

Active fire protection often is not considered as an IPL as it is post event for most scenarios and its availability and effectiveness may be affected by the fire / explosion which it is intended to contain; however, if the LOPA team can demonstrate it meets the requirements of an IPL for a given scenario, it may be used (e.g., if an activating system such as plastic piping or frangible switches are used) Note: Fire protection is identified as a “mitigation IPL” as it attempts to prevent a larger consequence subsequent to an event that has already occurred. This may be considered when assigning cost to commercial severity levels. Fireproof insulation can be used as an IPL for some scenarios if it meets the requirements of API and corporate standards

Source: Table 6.1, p 79 of the 2001 CCPS Concept Book “Layers of Protection Analysis”

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Table 6.

NHT Reformer Unit Layer of Protection Analysis

Probability of Failure on Demand (PFD) for Independent Protection Layers (IPLs)

Independent Protection Layer (IPL)

Probability of Failure on Demand (PFD)

Basic process control system, if not associated with the initiating event being considered

1 x 10-1

Operator response to alarm with at least 10 minutes response time

1 x 10-1

Relief valve

1 x 10-2

Rupture disc

1 x 10-2

Flame / detonation arrestors

1 x 10-2

Tandem seals

1 x 10-1

Dike

1 x 10-2

Underground drainage system

1 x 10-2

Open vent (no valve)

1 x 10-2

Fireproofing

1 x 10-2

Blast-wall / bunker

1 x 10-3

Identical redundant equipment ( e.g., identical relief valves)

1 x 10-1 (max credit)

Diverse redundant equipment (e.g., diverse relief devices)

1 x 10-1 to 1 x 10-2

Fire and gas detection (see Table 6)

1 x 10-1 to 1 x 10-2

Other events

Use experience of personnel

Source: Table 6.3, page 92; Table 6.4, p 96; Table 6.5, page 103 of the 2001 CCPS Concept Book “Layers of Protection Analysis”.

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2.5

NHT Reformer Unit Layer of Protection Analysis

Rules for Independent Protection Layers (IPLs)

Each protection layer counted must be truly independent of the other protection layers. This means there must be no failure that can deactivate two or more protection layers. If a Safety Instrumented System (SIS) is initiated by more than one sensor, the consequence of failure may be different for each sensor and therefore, each failure is considered separately. If the consequences are different for each failure, the function is separated into more than one function and the IPL determined for each. If an SIS initiates more than one action, the consequences of failure may be different for each final actuation and therefore, each failure shall be considered separately. If consequences are different for each failure, the function is separated into more than one function and the IPL determined for each. 2.5.1

Intermittent Hazard (Not Always Present)

There may be some hazards that are only present during certain job tasks, such as startup, shutdown, regeneration, etc. The following equation is used to determine the credit for this type of protection layer: ICL = ICL x [(time at risk)/(total time)] 2.5.2

Mechanical Relief Devices – Relief Valves

The following rules apply to the use of relief valves as protection layers: •

Relief system is sized for all reasonably foreseeable failures of process and process control to completely mitigate the scenario under consideration

•

Disposal of relieved materials is to a safe location

•

Relief discharge does not cause significant environmental or commercial consequences

•

Operating experience indicates that the relief valves to be used are satisfactory for the process application with the appropriate test intervals

•

If PSV is in dirty or plugging service, no credit is allowed

•

When there are two relief devices, each 100% sized for the scenarios, then an additional credit can be taken (should be at least an order of magnitude lower than that used for the first, generally 1x 10-1).

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2.5.3

NHT Reformer Unit Layer of Protection Analysis

Check Valves

Check valves are notoriously unreliable, but can be considered a LOPA safeguard on a case-by-case basis. Some of the considerations include:

2.5.4

•

Multiple check valves in series

•

Clean service

•

High differential pressure (< 100 psi) to hold valve closed and prevent leakage

•

Defined testing program

BPCS

The Basis Process Control System (BPCS) has several rules associated with their use as IPLs:

2.5.5

•

If a BPCS control loop is a cause, the alarms generated by that control loop cannot be counted as a protection layer. Alarms separate from the control loop may be used as protection for the failure of that control loop if the operator response time is adequate.

•

A control loop in the BPCS, whose normal action would compensate for the initiating event, can be considered as a protection layer. For example, an initiating cause for high reactor pressure could be failure of a local upstream pressure regulator; the normal action of the reactor pressure controller would be to close the inlet PV, thus providing protection against the impact event.

•

Failure mode of the final element is to the safe state

Operator Response to Alarm

Risk reduction for “Operator Response to Alarms” can only be counted once. Alarms are identified for all causes of the initiating event. The following must be confirmed as true before allowing credit for operator response: •

Alarm is independent of the cause and BPCS control loop claimed as a protection layer

•

Operator always present and available at the alarm point

•

Alarm gives clear indication of the hazard

•

Operator will detect the alarm among potentially many other alarms

•

Operator has time to diagnose and take corrective action (within 10 minutes)

•

Operator is trained in the proper procedures and response associated with the alarm state and the response steps are identified as critical in the procedure

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2.6

Vulnerability Factors

2.6.1

Ignition Probability

NHT Reformer Unit Layer of Protection Analysis

There are many releases that are not ignited. Ignition probabilities used in this study are: •

P ~ 0.3 for flammable liquids and gases

•

P ~ 0.1 -> 0.3 for volatile liquids

•

P < 0.1 for heavy liquids

Where P = probability of ignition 2.6.2

Person Present

To qualify as a safety related scenario, a person must be in the area where the incident occurs. Credit is taken for time not in the hazard zone. For example, during operator rounds, if a pump seal fire were to occur, in order for there to be an injury, the operator must be near the pump. The operator may only be near the pump for 30 minutes out of his shift. The following vulnerability factors should be applied when appropriate: VFp = 1.0 if people are present in the hazard zone all the time VFp = 0.5 if people are present in the hazard zone for less than 12 hours per day VFp = 0.1 if people are present in the hazard zone for less than 1-2 hours per day For environmental and commercial scenarios, the person present is not used. 2.7

LOPA Calculation

Using the numerical values identified in the preceding steps, a simple calculation is performed to determine the LOPA ratio. LOPA is limited to evaluating a single cause-consequence pair as a scenario. The numerator of the LOPA ratio is the Target Frequencies (TF), which is the company’s risk tolerance for that scenario. The denominator of the LOPA ratio is the product of the Initiating Cause Likelihood (ICL), the Probability of Failure on Demand (PFD) of each Independent Protection Layer (IPL) identified and the Vulnerability Factor (VF). The formula for calculating the LOPA ratio is presented below:

LOPA Ratio ( Safety) =

TFSafety ICL ∗ PFD1 ∗ PFD2 ∗ PFD3... ∗VFi ∗VFp

LOPA Ratio ( Environmen tal ) =

LOPA Ratio (Commercial ) = RRS Engineering, LLC October 31, 2008

TFEnvironmen tal ICL ∗ PFD 1 ∗ PFD 2 ∗ PFD 3...

TFCommercial ICL ∗ PFD1 ∗ PFD 2 ∗ PFD 3... * VFi Page 12

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NHT Reformer Unit Layer of Protection Analysis

If the LOPA ratio is greater than or equal to one, then the scenario “passes LOPA”. Existing protection layers in place are adequate. If the LOPA ratio is less than one, then the scenario “fails LOPA.” Additional protection layers are needed.

3.0

SIS EVALUATION

LOPA was used to determine the required and Safety Integrity Level (SIL) for a Safety Instrumented System (SIS). To do this, the LOPA ratio was calculated without giving any credit to the existing SIS. The required SIL was then found by using Table 7. Table 7.

Integrity Levels (SILs) for a Safety Instrumented System (SIS) LOPA Ration

Required SIL, EIL, CIL

10-0 - 10-1

No special integrity requirements

10-1 - 10-2

1

10-2 - 10-3

2

10-3 - 10-4

3

The LOPA worksheets for this project are contained in Section 5. The SIL determinations derived from the study are shown in Table 8. Table 8. LOPA Ref.

Safety Integrity Level (SIL) Determination SIS Number and Function

Required Integrity Level S

E

C

2.1

LSHH-592 High high level switch that closes blanket fuel gas valve PV-593B on high high level in the drum.

0

1

0

4.2

FSLL-915/918 Flow indication with low flow alarms and interlocks that shutdown the heater on low low flow through a heater pass.

1

2

2

5.8

PSLL-1389 Interlock that isolates the fuel gas from the heater on low low fuel gas pressure.

2

2

2

5.11

PSLL-1379 Interlock that isolates the pilot gas from the heater on low low pilot gas pressure.

1

2

2

12.2

FSLL-645/647/655 Low flow shutdown Fractionator Reboiler (H-102).

1

2

2

13.8

PSLL-1399 Interlock that isolates the fuel gas from the heater on low low fuel gas.

2

2

2

13.11

PSLL-1393 Interlock that isolates the pilot gas from the heater on low low pilot gas pressure.

0

1

1

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NHT Reformer Unit Layer of Protection Analysis SIS Number and Function

Required Integrity Level S

E

C

19.2 23.2 25.2

PSL-837 Interlock that stars the spare combustion air blower fan on low combustion air pressure.

1

1

1

19.2 23.2 25.2

SSL-1294 Interlock that shuts down the heater on shutdown of the induced draft fan.

1

1

1

19.8

PSLL-1732 Interlock that isolates the fuel gas from the heater on low low fuel gas pressure.

0

1

1

28.1

LSHH-256 Interlock that shuts down the compressors on high high level.

2

2

3

29.2

FSLL-106 Interlock that isolates the fuel gas to the charge heater and interheaters on low low recycle hydrogen flow.

1

2

2

30.9

PDSHH-171 that shuts down compressor C-2A on high high differential pressure between the suction and discharge of the first stage.

1

1

1

30.9

PDSHH-175 that shuts down compressor C-2B on high high differential pressure between the suction and discharge of the first stage.

1

1

1

32.1

LSHH-179 that shuts down the booster compressor on high high level.

2

2

3

33.8

PDSHH-173 that shuts down compressor C-2A on high high differential pressure between the suction and discharge lines.

1

1

1

33.8

PDSHH-177 that shuts down compressor C-2B on high high differential pressure between the suction and discharge lines.

1

1

1

39.1

LSHH-181 that shuts down the booster compressor on high high level. *This scenario was revisited during the June 21st meeting.

1

2

2

49.2

FSLL-783/784/785/786 Interlocks that isolate the flue gas from the charge heater, interheaters, and Depentanizer Reboiler trim heater on low low flow.

1

2

2

72.2

LSLL-38 that shuts down the compressor and prevents restart on low low level in the overhead seal oil tank. *This scenario was revisited during the June 21st meeting.

1

1

1

72.2

LSL-57 that starts the auxiliary lube oil pump on low level in the overhead seal oil tank. *This scenario was revisited during the June 21st meeting.

2

2

2

72.9

PSL-40 Interlock that starts the spare pump on low lube oil pressure. *This scenario was revisited during the June 21st meeting.

1

2

2

73.8

PSL-77/78 shuts down the compressor on low lube oil pressure. *This scenario was revisited during the June 21st meeting.

1

2

1

RRS Engineering, LLC October 31, 2008

Page 14

Project No. 07-099 Revision No. 2

TOTAL Petrochemicals Port Arthur Refinery LOPA Ref.

4.0

NHT Reformer Unit Layer of Protection Analysis SIS Number and Function

Required Integrity Level S

E

C

73.12

TSHH-107/108/109/110 shuts down the compressor and prevents compressor restart if there is a high high gas discharge temperature from the first stage.

0

1

1

80.10

FSL-394 shuts down the CDR on low low nitrogen flow.

1

1

1

RECOMMENDATIONS

If during the LOPA study, the LOPA analysis indicated there were not enough safeguards or an additional SIS was needed, then the Study Team made additional recommendations. Table 9 identifies the recommendations from the LOPA Study.

RRS Engineering, LLC October 31, 2008

Page 15

Project No. 07-099 Revision No. 2

TOTAL Petrochemicals Port Arthur Refinery

NHT Reformer Unit Layer of Protection Analysis

Table 9.

Recommendations

Rec. No.

Scenario Number

1

1.1

Consider adding a tested independent alarm or a SIL 1 shutdown system.

2

2.1

Ensure that LAH-910 high level alarm is on a routine testing schedule.

3

2.1

Ensure that interlock LSHH-592 that closes blanket fuel gas valve PV-593B on high high level in the drum is designed for EIL 1.

4

4.2

Consider adding an additional alarm to indicate loss of hydrogen and hydrocarbon flow to Charge Heater (H-101) on each pass and ensure it is on a routine testing schedule.

5

4.2

Ensure that interlocks FSLL-915 through 918 are designed for SIL 1.

6

5.8

Ensure PSLL-1389 is designed for SIL 2.

7

5.11

Ensure that PSLL-1379 is designed for SIL 2.

8

12.2

Consider adding an additional alarm to indicate loss of hydrocarbon flow to Fractionator Reboiler (H-102) on each pass and ensure it is on a routine testing schedule.

9

12.2

Ensure that interlocks FSLL-645/647/655 are designed for SIL 1.

10

13.8

Ensure that Interlock PSLL-1399 is designed for SIL 2.

11

13.11

Review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

12

19.2

Ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

13

19.8

Ensure that pressure indication PI-868 with low pressure alarm is on a routine testing schedule.

14

28.1

Ensure that high level alarm LH-257 is on a routine testing schedule.

15

28.1

Ensure that Interlock LSHH-256 that shuts down the compressors on high high level is designed for SIL 1.

16

28.1

Evaluate if Interlock LSHH-256 should be designed for Environmental EIL 2 and Commercial CIL 3.

17

29.2

Ensure that interlock FSLL-106 is designed for SIL 1.

18

30.9

Ensure that Interlock PDSHH-171 that shuts down compressor C-2A on high-high differential pressure between the suction and discharge of the firststage and/or Interlock PDSHH-175 that shuts down compressor C2-B on high high differential pressure between the suction and discharge of the first stage are designed for SIL 1.

19

32.1

Ensure that LH-178 is on a routine testing schedule.

20

32.1

Ensure that LSHH-179 that shuts down the booster compressor on high-high level is designed for SIL 1.

21

32.1

Evaluate if Interlock LSHH-179 should be designed for an Environmental EIL 2 and/or Commercial CIL 3.

RRS Engineering, LLC October 31, 2008

Recommendation

Page 16

Project No. 07-099 Revision No. 2

TOTAL Petrochemicals Port Arthur Refinery

NHT Reformer Unit Layer of Protection Analysis

Rec. No.

Scenario Number

Recommendation

22

33.8

Ensure that PDSHH-173 that shuts down compressor C-2A on high-high differential pressure between the suction and discharge lines and/or PDSHH177 that shuts down compressor C-2B on high-high differential pressure between the suction and discharge lines is designed for SIL 1.

23

39.1

Confirm the level alarm for the Unibon Compressor Suction Drum (13C1A/B) is independent of the level control valve and is on a routine testing schedule.

24

39.1

Ensure that LSH-180 high level alarm is on a routine testing schedule.

25

39.1

Confirm the level alarm for the TDP Compressor Suction Drum is independent of the level control valve and is on a routine testing schedule.

26

39.1

Ensure that LSH-180 high level alarm is on a routine testing schedule.

27

49.2

Consider adding an additional alarm to indicate loss of hydrogen and hydrocarbon flow to (H-5) on each pass and ensure it is on a routine testing schedule.

28

49.2

Ensure that interlocks FSLL-783/784/785/786 are designed for SIL 1.

29

72.2

Consider bringing a low seal oil level alarm into DCS (independent of LV1437).

30

72.2

Ensure that Interlock LSLL-38 that shuts down the compressor and prevents restart on low-low level in the overhead seal oil tank and/or Interlock LSL-57 that starts the auxiliary lube oil pump on low level in the overhead seal oil tank are designed for SIL 2.

31

72.2

Evaluate if Interlock LSLL-38 and/or LSL-57 should be designed for Environmental EIL 2 and Commercial CIL 3.

32

72.9

Ensure that PAL-33 low pressure alarm is on a routine testing schedule.

33

72.9

Ensure that Interlock Interlock PSLL-32 shuts down compressor on low lube oil pressure is designed for SIL 1.

34

72.9

Evaluate if Interlock PSL-40 should be designed for Environmental EIL 2 and Commercial CIL3.

35

73.8

Ensure that low lube oil pressure alarm PAL-77/78 is on a routine testing schedule.

36

73.8

Ensure Interlock PSL-79/80 that shuts down Compressor is designed for SIL 1.

37

73.8

Evaluate if PSL-77 should be designed for Environmental EIL 2 and Commercial CIL 2.

38

73.12

Ensure that jacket water discharge temperature alarms TAH85/86/87/88/89/90/91/92 (local compressor panel and TDC) located on the first-stage compressor are on a routine testing schedule.

39

73.12

Evaluate if TSHH-107/108/109/110 that shut down the compressor and prevent compressor restart if there is a high-high gas discharge temperature from the second-stage should be designed for EIL 1 and CIL 1.

RRS Engineering, LLC October 31, 2008

Page 17

Project No. 07-099 Revision No. 2

TOTAL Petrochemicals Port Arthur Refinery

5.0

NHT Reformer Unit Layer of Protection Analysis

LOPA WORKSHEETS

RRS Engineering, LLC October 31, 2008

Page 18

Project No. 07-099 Revision No. 2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential hydrocarbons into process sewer, potential fire/explosion, potential personnel injury.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-03

Com:

Initiating Cause

Failure of raffinate splitter water boot level 1 1.00E-01 control valve.

Intermittent Hazard

P&ID: 3165-1-50-023

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

1.1

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio Recommendation

Safety:

0.010

1.00E-04

Env:

0.010

Com:

0.00

1. Consider adding a tested independent alarm or a SIL 1 shutdown system.

SIS No: SIS Function:

Required SIL Level: 1

EIL Level:

1

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

2.1

Overflow of liquid hydrocarbon to the unit flare header, potentially resulting in a high level in the Flare Gas KO Drum.

Target Frequency

Safety:

Initiating Cause

0.00E+00

Env:

1.00E-04

High flow, naphtha feed from the Crude Unit or Naphtha Stabilizer. (upstream flow control failure)

Intermittent Hazard

Com:

1.00E-02

1 1.00E-01

None

Vulnerability Factors

Ignition Probability Person Present

Independent Protection Layers

None

Process Design BPCS

LC-592 opens level control valve.

1.00E-01 None

PSV Op Response

None

LAH-910 high level alarm.

None

Other LOPA Ratio

Safety:

Recommendation

1.000

Env:

0.010

Com:

2. Ensure that LAH-910 high level alarm is on a routine testing schedule. 3. Ensure that interlock LSHH-592 that closes blanket fuel gas valve PV-593B on high high level in the drum is designed for EIL 1.

SIS No:

LSHH-592

SIS Function:

High high level switch LSHH-592 that closes blanket fuel gas valve PV-593B on high high level in the drum.

Required SIL Level: 0

EIL Level:

1

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

High level in feed surge drum. Tube failure in Charge Heater (H-101) resulting in release of hydrocarbon that could cause (a) a fire and/or explosion that may injure personnel in a medium-sized area and (b) environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Operator error, manual valve closed.

Intermittent Hazard

P&ID: 3165-1-50-002 Loop: F-0915, F-0916, F-0917, F-0918

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

4.2

1 1.00E-01

None

BPCS

None

PSV

None Flow indication FC-595 with low flow alarm.

Other LOPA Ratio

None None

Safety:

Recommendation

1.00E-04

1 1.00E-01

Process Design

Op Response

Com:

0.010

Env:

0.001

Com:

0.00

4. Consider adding an additional alarm to indicate loss of hydrogen and hydrocarbon flow to Charge Heater (H-101) on each pass and ensure it is on a routine testing schedule. 5. Ensure that interlocks FSLL-915 through 918 are designed for SIL 1.

SIS No:

FSLL-915-918

SIS Function:

Flow indication FI-915-918 with low flow alarms and interlocks FSLL-915-918 that shuts down the heater on low low flow through a heater pass.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

High level in feed surge drum. Tube failure in Charge Heater (H-101) resulting in release of hydrocarbon that could cause (a) a fire and/or explosion that may injure personnel in a medium-sized area and (b) environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Control valve FV-595 closing too far.

Intermittent Hazard

P&ID: 3165-1-50-002

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

4.2

1 1.00E-01

None

BPCS

None

PSV

None Flow indication FC-595 with low flow alarm.

None None

Other LOPA Ratio

1.00E-04

1 1.00E-01

Process Design

Op Response

Com:

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 4 to consider adding an additional alarm to indicate loss of hydrogen and hydrocarbon flow to Charge Heater (H-101) on each pass and ensure it is on a routine testing schedule. See LOPA Recommendation 5 to ensure that interlocks FSLL-915 through 918 are designed for SIL 1.

SIS No:

FI-915-918

SIS Function:

Flow indication FI-915-918 with low flow alarms and interlocks FSLL-915-918 that shuts down the heater on low low flow through a heater pass.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

High level in feed surge drum. Tube failure in Charge Heater (H-101) resulting in release of hydrocarbon that could cause (a) a fire and/or explosion that may injure personnel in a medium-sized area and (b) environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Pump tripping off.

Intermittent Hazard

P&ID: 3165-1-50-002

None

Vulnerability Factors

Ignition Probability

None

None

BPCS

None

PSV

None Flow indication FC-595 with low flow alarm.

None None

Other LOPA Ratio

1.00E-04

1 1.00E-01

Process Design

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

4.2

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 4 to consider adding an additional alarm to indicate loss of hydrogen and hydrocarbon flow to Charge Heater (H-101) on each pass and ensure it is on a routine testing schedule. See LOPA Recommendation 5 to ensure that interlocks FSLL-915 through 918 are designed for SIL 1.

SIS No:

FI-915-918

SIS Function:

Flow indication FI-915-918 with low flow alarms and interlocks FSLL-915-918 that shuts down the heater on low low flow through a heater pass.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

High level in feed surge drum. Tube failure in Charge Heater (H-101) resulting in release of hydrocarbon that could cause (a) a fire and/or explosion that may injure personnel in a medium-sized area and (b) environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Low level, feed surge drum.

Intermittent Hazard

P&ID: 3165-1-50-002

None

Vulnerability Factors

Ignition Probability

None

None

BPCS

None

PSV

None Flow indication FC-595 with low flow alarm.

None None

Other LOPA Ratio

1.00E-04

1 1.00E-01

Process Design

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

4.2

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 4 to consider adding an additional alarm to indicate loss of hydrogen and hydrocarbon flow to Charge Heater (H-101) on each pass and ensure it is on a routine testing schedule. See LOPA Recommendation 5 to ensure that interlocks FSLL-915 through 918 are designed for SIL 1.

SIS No:

FI-915-918

SIS Function:

Flow indication FI-915-918 with low flow alarms and interlocks FSLL-915-918 that shuts down the heater on low low flow through a heater pass.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

High level in feed surge drum. Tube failure in Charge Heater (H-101) resulting in release of hydrocarbon that could cause (a) a fire and/or explosion that may injure personnel in a medium-sized area and (b) environmental impact in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Plugged strainer in the pump suction line. 1 1.00E-01 None P&ID: 3165-1-50-002

Vulnerability Factors

Ignition Probability

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Flow indication FC-595 with low flow alarm.

None None

Other LOPA Ratio

1.00E-04

None

Person Present Independent Protection Layers

4.2

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 4 to consider adding an additional alarm to indicate loss of hydrogen and hydrocarbon flow to Charge Heater (H-101) on each pass and ensure it is on a routine testing schedule. See LOPA Recommendation 5 to ensure that interlocks FSLL-915 through 918 are designed for SIL 1.

SIS No:

FI-915-918

SIS Function:

Flow indication FI-915-918 with low flow alarms and interlocks FSLL-915-918 that shuts down the heater on low low flow through a heater pass.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Louver control valve PV-616 closing too 1 1.00E-01 far.

Intermittent Hazard

P&ID: 3165-1-50-055A Loop: F-0890

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

5.2

Process Design

1 1.00E-01

1.00E-02

Blowout doors.

BPCS

None

PSV

None

Op Response

1.00E-04

Flue gas analyzer AI-601 with low alarm.

1.00E-01

Pressure indication PC-616 with low pressure alarm on preheated air duct to heater. Pressure indication PC-615 with low pressure alarm on the flue gas duct. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

FSLL-890

SIS Function:

Interlock FSLL-890 that switches the heater to natural draft operation on low low combustion air flow.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Stack damper closing too far.

Intermittent Hazard

P&ID: 3165-1-50-055A Loop: F-0890

None

Vulnerability Factors

Ignition Probability

None

Process Design

1.00E-04

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

5.2

Flue gas analyzer AI-601 with low alarm.

1.00E-01

Pressure indication PC-616 with low pressure alarm on preheated air duct to heater. Pressure indication PC-615 with low pressure alarm on the flue gas duct. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

FSLL-890

SIS Function:

Interlock FSLL-890 that switches the heater to natural draft operation on low low combustion air flow.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Combustion air fan tripping off.

Intermittent Hazard

P&ID: 3165-1-50-055A Loop: F-0890

None

Vulnerability Factors

Ignition Probability

None

Process Design

1.00E-04

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

5.2

Flue gas analyzer AI-601 with low alarm.

1.00E-01

Pressure indication PC-616 with low pressure alarm on preheated air duct to heater. Pressure indication PC-615 with low pressure alarm on the flue gas duct. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

FSLL-890

SIS Function:

Interlock FSLL-890 that switches the heater to natural draft operation on low low combustion air flow.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Induced draft fan tripping off.

Intermittent Hazard

P&ID: 3165-1-50-055A Loop: F-0890

None

Vulnerability Factors

Ignition Probability

None

Process Design

1.00E-04

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

5.2

Flue gas analyzer AI-601 with low alarm.

1.00E-01

Pressure indication PC-616 with low pressure alarm on preheated air duct to heater. Pressure indication PC-615 with low pressure alarm on the flue gas duct. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

SSL-1042

SIS Function:

Interlock SSL-1042 that opens the stack damper on shutdown of the induced draft fan.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Louver control valve PV-615 closing too 1 1.00E-01 far.

Intermittent Hazard

P&ID: 3165-1-50-055A Loop: F-0890

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

5.2

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

1.00E-04

Flue gas analyzer AI-601 with low alarm.

1.00E-01

Pressure indication PC-616 with low pressure alarm on preheated air duct to heater. Pressure indication PC-615 with low pressure alarm on the flue gas duct. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

FSLL-890

SIS Function:

Interlock FSLL-890 that switches the heater to natural draft operation on low low combustion air flow.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low pressure in fuel gas header.

Com:

1.00E-04

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

5.8

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

6. Ensure PSLL-1389 is designed for SIL 2.

SIS No:

PSLL-1389

SIS Function:

Interlock PSLL-1389 that isolates the fuel gas from the heater on low low fuel gas pressure.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Control valve FV-888 closing too far.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

5.8

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 6 to ensure PSLL-1389 is designed for SIL 2.

SIS No:

PSLL-1389

SIS Function:

Interlock PSLL-1389 that isolates the fuel gas from the heater on low low fuel gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Operator error, manual valve closed.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

5.8

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

See LOPA Recommendation 6 to ensure PSLL-1389 is designed for SIL 2.

SIS No:

PSLL-1389

SIS Function:

Interlock PSLL-1389 that isolates the fuel gas from the heater on low low fuel gas pressure.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1382A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.001

1.00E-04

None

Person Present Independent Protection Layers

5.8

Env:

0.001

Com:

0.00

See LOPA Recommendation 6 to ensure PSLL-1389 is designed for SIL 2.

SIS No:

PSLL-1389

SIS Function:

Interlock PSLL-1389 that isolates the fuel gas from the heater on low low fuel gas pressure.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a mediumsized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low fuel pressure.

Com:

1.00E-04

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

5.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

7. Ensure that PSLL-1379 is designed for SIL 2.

SIS No: SIS Function:

Interlock PSLL-1379 that isolates the pilot gas from the heater on low low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a mediumsized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Carryover of liquid as a result of high level 1 1.00E-01 in fuel gas KO drum.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

5.11

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

See LOPA Recommendation 7 to ensure that PSLL-1379 is designed for SIL 2.

SIS No:

PSLL-1379

SIS Function:

Interlock PSLL-1379 that isolates the pilot gas from the heater on low low pilot gas pressure.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a mediumsized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Total loss of combustion air.

Com:

1.00E-04

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

5.11

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

See LOPA Recommendation 7 to ensure that PSLL-1379 is designed for SIL 2.

SIS No:

PSLL-1379

SIS Function:

Interlock PSLL-1379 that isolates the pilot gas from the heater on low low pilot gas pressure.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a mediumsized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Manual valve closed.

Com:

1.00E-04

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

5.11

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

See LOPA Recommendation 7 to ensure that PSLL-1379 is designed for SIL 2.

SIS No:

PSLL-1379

SIS Function:

Interlock PSLL-1379 that isolates the pilot gas from the heater on low low pilot gas pressure.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a mediumsized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Local control valve PCV-298 closing too 1 1.00E-01 far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

5.11

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

See LOPA Recommendation 7 to ensure that PSLL-1379 is designed for SIL 2.

SIS No:

PSLL-1379

SIS Function:

Interlock PSLL-1379 that isolates the pilot gas from the heater on low low pilot gas pressure.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a mediumsized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1381A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.010

1.00E-04

None

Person Present Independent Protection Layers

5.11

Env:

0.001

Com:

0.00

See Recommendation 7 to ensure that PSLL-1379 is designed for SIL 2.

SIS No: SIS Function:

Interlock PSLL-1379 that isolates the pilot gas from the heater on low low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a mediumsized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

High pressure transient from the fuel gas 1 1.00E-01 supply header.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

5.11

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

See LOPA Recommendation 7 to ensure that PSLL-1379 is designed for SIL 2.

SIS No:

PSLL-1379

SIS Function:

Interlock PSLL-1379 that isolates the pilot gas from the heater on low low pilot gas pressure.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Release of hydrocarbon resulting in (a) a fire in the firebox, potentially causing structural damage (e.g., collapse of the heater stack) that may injure personnel and rupture process equipment in a medium-sized area around the heater, (b) a fire and/or explosion outside the heater that may injure personnel in a medium-sized area, and (c) environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

P-103A/B stops.

Intermittent Hazard

P&ID: 3165-1-50-007 Loop: F-0645, F-0647, F-0655

None

Vulnerability Factors

Ignition Probability

None

None

BPCS

None

PSV

None

Op Response

None

Other

None Safety:

Recommendation

0.010

1.00E-04

1 1.00E-01

Process Design

LOPA Ratio

Com:

1 1.00E-01

Person Present Independent Protection Layers

12.2

Env:

0.001

Com:

0.00

8. Consider adding an additional alarm to indicate loss of hydrocarbon flow to Fractionator Reboiler (H-102) on each pass and ensure it is on a routine testing schedule. 9. Ensure that interlocks FSLL-645/647/655 are designed for SIL 1.

SIS No:

FSLL-645/647/655

SIS Function:

Low flow shutdowns FSLL-645/647/655 shuts down Fractionator Reboiler (H-102).

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Release of hydrocarbon resulting in (a) a fire in the firebox, potentially causing structural damage (e.g., collapse of the heater stack) that may injure personnel and rupture process equipment in a medium-sized area around the heater, (b) a fire and/or explosion outside the heater that may injure personnel in a medium-sized area, and (c) environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Control valve or manual valve closed.

Intermittent Hazard

P&ID: 3165-1-50-007 Loop: F-0645, F-0647, F-0655

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

12.2

1 1.00E-01

None

BPCS

None

PSV

None

Op Response

None

Other

None Safety:

Recommendation

0.010

1.00E-04

1 1.00E-01

Process Design

LOPA Ratio

Com:

Env:

0.001

Com:

0.00

See LOPA Recommendation 8 to consider adding an additional alarm to indicate loss of hydrocarbon flow to Fractionator Reboiler (H-102) on each pass and ensure it is on a routine testing schedule. See LOPA Recommendation 9 to ensure that interlocks FSLL-645/647/655 are designed for SIL 1.

SIS No:

FSLL-645/647/655

SIS Function:

Low flow shutdowns FSLL-645/647/655 shuts down Fractionator Reboiler (H-102).

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Stack damper closing too far.

Intermittent Hazard

P&ID: 3165-1-50-055B Loop: F-0898

None

Vulnerability Factors

Ignition Probability

None

Process Design

1.00E-04

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

13.2

Flue gas oxygen analyzer AI-664 with low alarm.

1.00E-01

Pressure indication PC-616 with low pressure alarm on preheated air duct to the heater. Pressure indication PC-615 with low pressure alarm located on the flue gas duct. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

FSLL-898

SIS Function:

Interlock FSLL-898 that switches the heater to natural draft on low low combustion air flow.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Induced draft fan tripping off.

Intermittent Hazard

P&ID: 3165-1-50-055B Loop: F-0898

None

Vulnerability Factors

Ignition Probability

None

Process Design

1.00E-04

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

13.2

Flue gas oxygen analyzer AI-664 with low alarm.

1.00E-01

Pressure indication PC-616 with low pressure alarm on preheated air duct to the heater. Pressure indication PC-615 with low pressure alarm located on the flue gas duct. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

FSLL-898

SIS Function:

Interlock FSLL-898 that switches the heater to natural draft on low low combustion air flow.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Combustion air fan tripping off.

Intermittent Hazard

P&ID: 3165-1-50-055B Loop: F-0898

None

Vulnerability Factors

Ignition Probability

None

Process Design

1.00E-04

1 1.00E-01

1.00E-02

Blast Doors.

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

13.2

Flue gas oxygen analyzer AI-664 with low alarm.

1.00E-01

Pressure indication PC-616 with low pressure alarm on preheated air duct to the heater. Pressure indication PC-615 with low pressure alarm located on the flue gas duct. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

FSLL-898 or SSL-1042

SIS Function:

Interlock FSLL-898 that switches the heater to natural draft on low low combustion air flow. Interlock SSL-1042 that opens the stack damper on shutdown of the induced draft fan.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Louver control valve PC-616 closing too 1 1.00E-01 far.

Intermittent Hazard

P&ID: 3165-1-50-055B Loop: F-0898

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

13.2

Process Design

1 1.00E-01

1.00E-02

Blast Doors.

BPCS

None

PSV

None

Op Response

1.00E-04

Flue gas oxygen analyzer AI-664 with low alarm.

1.00E-01

Pressure indication PC-616 with low pressure alarm on preheated air duct to the heater. Pressure indication PC-615 with low pressure alarm located on the flue gas duct. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

FSLL-898

SIS Function:

Interlock FSLL-898 that switches the heater to natural draft on low low combustion air flow.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Louver control valve PV-615 closing too 1 1.00E-01 far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

13.2

Process Design

1 1.00E-01

1.00E-02

Blast Doors.

BPCS

None

PSV

None

Op Response

Flue gas oxygen analyzer AI-664 with low alarm.

1.00E-01

Pressure indication PC-616 with low pressure alarm on preheated air duct to the heater. Pressure indication PC-615 with low pressure alarm located on the flue gas duct. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

FSLL-898

SIS Function:

Interlock FSLL-898 that switches the heater to natural draft on low low combustion air flow.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low pressure in fuel gas header.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

13.8

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

10. Ensure that Interlock PSLL-1399 is designed for SIL 2.

SIS No:

PSLL-1399

SIS Function:

Interlock PSLL-1399 that isolates the fuel gas from the heater on low low fuel gas pressure.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Control valve FV-897 closing too far.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

13.8

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

See LOPA Recommendation 10 to ensure that Interlock PSLL-1399 is designed for SIL 2.

SIS No:

PSLL-1399

SIS Function:

Interlock PSLL-1399 that isolates the fuel gas from the heater on low low fuel gas pressure.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Operator error, manual valve closed.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

13.8

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

See LOPA Recommendation 10 to ensure that Interlock PSLL-1399 is designed for SIL 2.

SIS No:

PSLL-1399

SIS Function:

Interlock PSLL-1399 that isolates the fuel gas from the heater on low low fuel gas pressure.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in (a) injury to personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1384A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.001

1.00E-04

None

Person Present Independent Protection Layers

13.8

Env:

0.001

Com:

0.00

See LOPA Recommendation 10 to ensure that Interlock PSLL-1399 is designed for SIL 2.

SIS No:

PSLL-1399

SIS Function:

Interlock PSLL-1399 that isolates the fuel gas from the heater on low low fuel gas pressure.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low pressure from fuel gas supply (OSBL).

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

13.11

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

None Pilots are fueled by Purchased Natural Gas.

Other LOPA Ratio

Safety:

Recommendation

1.000

Env:

None 0.100

Com:

0.10

11. Review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1393

SIS Function:

Interlock PSLL-1393 that isolates the pilot gas from the heater on low-low pilot gas pressure

Required SIL Level: 0

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Carryover of liquid as a result of high 1 1.00E-01 level- fuel gas KO drum that could result in liquid hydrocarbon pooling and fire in the bottom of the firebox for the reformer charge heater.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

13.11

Process Design

1 1.00E-01

Blast doors.

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-893 with low pressure alarm

1.00E-01

Other

Pilots are fueled by Purchased Natural Gas.

None

LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1393

SIS Function:

Interlock PSLL-1393 that isolates the pilot gas from the heater on low-low pilot gas pressure

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Local control valve PCV-1683 closing too 1 1.00E-01 far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

13.11

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Pressure indication PI-893 with low pressure alarm.

None

Other

Pilots are fueled by Purchased Natural Gas.

None

LOPA Ratio

Safety:

Recommendation

1.000

Env:

0.100

Com:

0.10

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1393

SIS Function:

Interlock PSLL-1393 that isolates the pilot gas from the heater on low-low pilot gas pressure

Required SIL Level: 0

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1383A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Pressure indication PI-893 with low pressure alarm

1.00E-01

Other

Pilots are fueled by Purchased Natural Gas.

None

LOPA Ratio

Safety:

Recommendation

1.00E-04

None

Person Present Independent Protection Layers

13.11

10.000

Env:

1.000

Com:

1.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1393

SIS Function:

Interlock PSLL-1393 that isolates the pilot gas from the heater on low-low pilot gas pressure

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

High pressure transient from the fuel gas 1 1.00E-01 supply header (OSBL)

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

13.11

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Pressure indication PI-893 with low pressure alarm

None

Other

Pilots are fueled by Purchased Natural Gas.

None

LOPA Ratio

Safety:

Recommendation

1.000

Env:

0.100

Com:

0.10

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1393

SIS Function:

Interlock PSLL-1393 that isolates the pilot gas from the heater on low-low pilot gas pressure

Required SIL Level: 0

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout H-1, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Induced draft fan tripping off.

Intermittent Hazard

P&ID: 3165-1-50-052A Loop: F-0862

None

Vulnerability Factors

Ignition Probability

None

1.00E-04

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

19.2

Flue gas oxygen analyzer AI-483 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on the preheated air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

12. Ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 that start the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 that shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout H-1, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Combustion air blower fan tripping off.

Intermittent Hazard

P&ID: 3165-1-50-052A Loop: F-0862

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

19.2

1.00E-04

1 1.00E-01

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Com:

Flue gas oxygen analyzer AI-483 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on the preheated air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 that start the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 that shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout H-1, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Control valve FV-862A/B closing too far. 1 1.00E-01 P&ID: 3165-1-50-052A None Loop: F-0862

Vulnerability Factors

Ignition Probability

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

1.00E-04

None

Person Present Independent Protection Layers

19.2

Flue gas oxygen analyzer AI-483 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on the preheated air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 that start the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 that shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout H-1, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Louver control valve PV-834A/B closing 1 1.00E-01 too far.

Intermittent Hazard

P&ID: 3165-1-50-052A Loop: F-0862

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

19.2

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

1.00E-04

Flue gas oxygen analyzer AI-483 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on the preheated air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 that start the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 that shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout H-1, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Louver control valve PV-829 closing too 1 1.00E-01 far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

19.2

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Flue gas oxygen analyzer AI-483 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on the preheated air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 that start the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 that shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout H-2, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Stack damper closing too far.

Intermittent Hazard

P&ID: 3165-1-50-052A Loop: F-0858

None

Vulnerability Factors

Ignition Probability

None

1.00E-04

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

19.2

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on preheated air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Control valve FV-866 closing too far.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

19.8

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Pressure indication PI-868 with low pressure alarm.

None

Other LOPA Ratio

None

Safety:

Recommendation

1.000

Env:

0.100

Com:

0.10

13. Ensure that pressure indication PI-868 with low pressure alarm is on a routine testing schedule.

SIS No:

PSLL-1732

SIS Function:

Interlock PSLL-1732 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low pressure from fuel gas supply (OSBL).

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

19.8

Process Design

1 1.00E-01

None

Blast doors.

BPCS

None

PSV

None

Op Response

Pressure indication PI-868 with low pressure alarm

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 13 to ensure that pressure indication PI-868 with low pressure alarm is on a routine testing schedule.

SIS No:

PSLL-1732

SIS Function:

Interlock PSLL-1732 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1347A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Pressure indication PI-868 with low pressure alarm

None None

Other LOPA Ratio

1.00E-04

None

Person Present Independent Protection Layers

19.8

Safety:

Recommendation

1.000

Env:

0.100

Com:

0.10

See LOPA Recommendation 13 to ensure that pressure indication PI-868 with low pressure alarm is on a routine testing schedule.

SIS No:

PSLL-1732

SIS Function:

Interlock PSLL-1732 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in mediumsized area and potential environmental impacts in a small area

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Carryover of a liquid as a result of high 1 1.00E-01 level-fuel gas KO drum that could result in liquid hydrocarbon pooling and fire in the bottom of the firebox for the reformer charge heater.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

19.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pilot gas pressure indication PI-869 with low pressure alarm.

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1724

SIS Function:

Interlock PSLL-1724 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in mediumsized area and potential environmental impacts in a small area

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Local control valve PCV-1348 closing too 1 1.00E-01 far

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

19.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-868 with low pressure alarm and local pressure indication PI-866A.

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1732

SIS Function:

Interlock PSLL-1732 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in mediumsized area and potential environmental impacts in a small area

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1346A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-868 with low pressure alarm

Other LOPA Ratio

1.00E-04

None

Person Present Independent Protection Layers

19.11

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1732

SIS Function:

Interlock PSLL-1732 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in mediumsized area and potential environmental impacts in a small area

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

High pressure transient from the fuel gas 1 1.00E-01 supply header (OSBL)

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

19.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-868 with low pressure alarm

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1732

SIS Function:

Interlock PSLL-1732 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in mediumsized area and potential environmental impacts in a small area

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Low fuel pressure due to control valve FV- 1 1.00E-01 866 closing too far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

19.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-868 with low pressure alarm

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1732

SIS Function:

Interlock PSLL-1732 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in mediumsized area and potential environmental impacts in a small area

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low fuel pressure due to low pressure fuel gas header.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

19.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-868 with low pressure alarm.

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1732

SIS Function:

Interlock PSLL-1732 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in mediumsized area and potential environmental impacts in a small area

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low fuel pressure due to isolation valve XV-1347A or B is closed.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

19.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-868 with low pressure alarm

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1732

SIS Function:

Interlock PSLL-1732 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout H-1, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Stack damper closing too far.

Intermittent Hazard

P&ID: 3165-1-50-052A Loop: F-0862

None

Vulnerability Factors

Ignition Probability

None

Process Design

1.00E-04

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

21.2

Flue gas oxygen analyzer AI-483 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on the preheated air duct to the heater. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 that start the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 that shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout H-2, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Control valves FV-858A/B closing too far. 1 1.00E-01 P&ID: 3165-1-50-052A None Loop: F-0858

Vulnerability Factors

Ignition Probability

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

1.00E-04

None

Person Present Independent Protection Layers

21.2

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on preheated air duct to the heater. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout H-2, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Louver control valve PV-829 closing too 1 1.00E-01 far.

Intermittent Hazard

P&ID: 3165-1-50-052A Loop: F-0858

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

21.2

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

1.00E-04

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on preheated air duct to the heater. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout H-2, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Combustion air blower fan tripping off.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

21.2

Process Design

1 1.00E-01

Blast doors.

1.00E-02

BPCS

None

PSV

None

Op Response

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on preheated air duct to the heater. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout H-2, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Induced draft fan tripping off.

Com:

1.00E-04

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

21.2

Process Design

1 1.00E-01

Blast doors.

1.00E-02

BPCS

None

PSV

None

Op Response

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on preheated air duct to the heater. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout H-2, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Louver control valve PV-829 closing too 1 1.00E-01 far.

Intermittent Hazard

P&ID: 3165-1-50-052A Loop: F-0858

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

21.2

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

1.00E-04

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on the preheated air duct to the heater. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 that start the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 that shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential flameout H-2, potential firebox explosion, potential injury to personnel in a medium-sized area and environmental impact in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Louver control valve PV-834A/B closing 1 1.00E-01 too far.

Intermittent Hazard

P&ID: 3165-1-50-052A Loop: F-0862

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

21.2

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

1.00E-04

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on the preheated air duct to the heater. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 that start the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 that shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Combustion air blower fan tripping off.

Intermittent Hazard

P&ID: 3165-1-50-052A Loop: F-0858

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

21.2

Process Design

1.00E-04

1 1.00E-01

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Com:

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm located on the preheated air duct to the heater. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSL-837

SIS Function:

Interlock PSL-837 that starts the spare combustion air blower fan on low combustion air pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners flowing a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Induced draft fan tripping off.

Intermittent Hazard

P&ID: 3165-1-50-052A Loop: F-0858

None

Vulnerability Factors

Ignition Probability

None

Process Design

1.00E-04

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

21.2

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on the preheated air duct to the heater. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSL-837 and SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 that shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Control valve FV-860 closing too far.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

21.8

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PI-861 with low pressure alarm. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSLL-1731

SIS Function:

Interlock PSLL-1731 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Low pressure from fuel gas supply (OSBL)1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

21.8

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PI-861 with low pressure alarm. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No: SIS Function:

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1347A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

1.00E-04

None

Person Present Independent Protection Layers

21.8

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PI-861 with low pressure alarm. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No: SIS Function:

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of the combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Carryover of liquid as a result of high level- fuel gas KO drum.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

21.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pilot gas pressure indication PI-867 with low pressure alarm

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1724

SIS Function:

Interlock PSLL-1724 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of the combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Local control valve PCV-1348 closing too 1 1.00E-01 far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

21.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pilot gas pressure indication PI-867 with low pressure alarm

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1724

SIS Function:

Interlock PSLL-1724 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of the combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV01346A or B is closed 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pilot gas pressure indication PI-867 with low pressure alarm

Other LOPA Ratio

1.00E-04

None

Person Present Independent Protection Layers

21.11

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1724

SIS Function:

Interlock PSLL-1724 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of the combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

High pressure transient from the fuel gas 1 1.00E-01 supply header

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

21.11

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

Pilot gas pressure indication PI-867 with low pressure alarm

None

Other LOPA Ratio

None

Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1724

SIS Function:

Interlock PSLL-1724 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high firebox pressure if the induced draft fan trips or the stack damper is closed. Burner/pilot flameout.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Control valves FV-840A/B closing too far. 1 1.00E-01 None P&ID: 3165-1-50-051B Loop: F-0840

Vulnerability Factors

Ignition Probability

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

1.00E-04

None

Person Present Independent Protection Layers

23.2

Flue gas oxygen analyzer AI-462 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on preheated air duct to the heater. Other LOPA Ratio

None Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high firebox pressure if the induced draft fan trips or the stack damper is closed. Burner/pilot flameout.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Louver control valve PV-834A/B closing 1 1.00E-01 too far.

Intermittent Hazard

P&ID: 3165-1-50-051B Loop: F-0840

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

23.2

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

1.00E-04

Flue gas oxygen analyzer AI-462 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on preheated air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high firebox pressure if the induced draft fan trips or the stack damper is closed. Burner/pilot flameout.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Louver control valve PV-829 closing too 1 1.00E-01 far.

Intermittent Hazard

P&ID: 3165-1-50-051B Loop: F-0840

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

23.2

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

1.00E-04

Flue gas oxygen analyzer AI-462 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on preheated air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high firebox pressure if the induced draft fan trips or the stack damper is closed. Burner/pilot flameout.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Combustion air blower fan tripping off.

Intermittent Hazard

P&ID: 3165-1-50-051B Loop: F-0840

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

23.2

1.00E-04

1 1.00E-01

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Com:

Flue gas oxygen analyzer AI-462 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on preheated air duct to the heater. Other LOPA Ratio

None Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high firebox pressure if the induced draft fan trips or the stack damper is closed. Burner/pilot flameout.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Induced draft fan tripping off.

Intermittent Hazard

P&ID: 3165-1-50-051B Loop: F-0840

None

Vulnerability Factors

Ignition Probability

None

1.00E-04

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

23.2

Flue gas oxygen analyzer AI-462 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on preheated air duct to the heater. Other LOPA Ratio

None Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high firebox pressure if the induced draft fan trips or the stack damper is closed. Burner/pilot flameout.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Stack damper closing too far.

Intermittent Hazard

P&ID: 3165-1-50-051B Loop: F-0840

None

Vulnerability Factors

Ignition Probability

None

1.00E-04

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

23.2

Flue gas oxygen analyzer AI-462 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on preheated air duct to the heater. Other LOPA Ratio

None Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower fan on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low pressure- fuel gas header (OSBL)

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

23.8

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Flue gas oxygen analyzer AI-462 with low alarm.

1.00E-01

Pressure indication PI-848 with low pressure alarm None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No: SIS Function:

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Control valve FV-841 closing too far.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

23.8

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Flue gas oxygen analyzer AI-462 with low alarm.

1.00E-01

Pressure indication PI-848 with low pressure alarm None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSLL-1729

SIS Function:

Interlock PSLL-1729 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1347A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

1.00E-04

None

Person Present Independent Protection Layers

23.8

Flue gas oxygen analyzer AI-462 with low alarm.

1.00E-01

Pressure indication PI-848 with low pressure alarm. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No: SIS Function:

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of the combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low fuel pressure- fuel gas header

Intermittent Hazard Ignition Probability

1 1.00E-01

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pilot gas indication PI-849 with low pressure alarm

Other

Recommendation

1.00E-04

None

Person Present

LOPA Ratio

Com:

None

Vulnerability Factors

Independent Protection Layers

23.11

1.00E-01 None

Safety:

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No: SIS Function:

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of the combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Local control valve PCV-1348 closing too 1 1.00E-01 far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

23.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-848 with low pressure alarm

None

Other LOPA Ratio

1.00E-01

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1724

SIS Function:

Interlock PSLL-1724 that isolates the pilot gas form the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of the combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Carryover of liquid as a result of high level- fuel gas KO drum

Intermittent Hazard Ignition Probability

1 1.00E-01

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-848 with low pressure alarm

1.00E-01 None

Other

Recommendation

1.00E-04

None

Person Present

LOPA Ratio

Com:

None

Vulnerability Factors

Independent Protection Layers

23.11

Safety:

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No: SIS Function:

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of the combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1346A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-848 with low pressure alarm

Other LOPA Ratio Recommendation

1.00E-04

None

Person Present Independent Protection Layers

23.11

1.00E-01 None

Safety:

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No: SIS Function:

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of the combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

High pressure transient from the fuel gas 1 1.00E-01 supply header (OSBL)

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

23.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PI-848 with low pressure alarm None

Other LOPA Ratio Recommendation

Safety:

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No: SIS Function:

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high firebox pressure if the induced draft fan trips or the stack damper is closed. Burner/pilot flameout.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Control valves FV-850A/B closing too far. 1 1.00E-01 None P&ID: 3165-1-50-051-B Loop: F-0850

Vulnerability Factors

Ignition Probability

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

1.00E-04

None

Person Present Independent Protection Layers

25.2

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high firebox pressure if the induced draft fan trips or the stack damper is closed. Burner/pilot flameout.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Louver control valves PV-834A/B closing 1 1.00E-01 too far.

Intermittent Hazard

P&ID: 3165-1-50-051-B Loop: F-0850

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

25.2

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

1.00E-04

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high firebox pressure if the induced draft fan trips or the stack damper is closed. Burner/pilot flameout.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Louver control valve PC-829 closing too 1 1.00E-01 far.

Intermittent Hazard

P&ID: 3165-1-50-051-B Loop: F-0850

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

25.2

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

1.00E-04

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high firebox pressure if the induced draft fan trips or the stack damper is closed. Burner/pilot flameout.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Combustion air blower fan tripping off.

Intermittent Hazard

P&ID: 3165-1-50-051-B Loop: F-0850

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

25.2

1.00E-04

1 1.00E-01

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Com:

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high firebox pressure if the induced draft fan trips or the stack damper is closed. Burner/pilot flameout.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Induced draft fan tripping off.

Intermittent Hazard

P&ID: 3165-1-50-051-B Loop: F-0850

None

Vulnerability Factors

Ignition Probability

None

1.00E-04

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

25.2

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high firebox pressure if the induced draft fan trips or the stack damper is closed. Burner/pilot flameout.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Stack damper closing too far.

Intermittent Hazard

P&ID: 3165-1-50-051-B Loop: F-0850

None

Vulnerability Factors

Ignition Probability

None

1.00E-04

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

25.2

Flue gas oxygen analyzer AI-477 with low alarm.

1.00E-01

Pressure indication PC-834 with low pressure alarm on air duct to the heater. None

Other LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 12 to ensure that interlock PSL-837 or SSL-1294 are designed for SIL 1.

SIS No:

PSL-837 & SSL-1294

SIS Function:

Interlock PSL-837 starts the spare combustion air blower on low combustion air pressure. Interlock SSL-1294 shuts down the heater on shutdown of the induced draft fan.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low pressure- fuel gas header (OSBL)

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

25.8

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Flue gas oxygen analyzer AI-469 with low alarm.

None

Other LOPA Ratio

1.00E-01

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSLL-1730

SIS Function:

Interlock PSLL-1730 that isolates the fuel gas from the heaters on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Control valve FV-851 closing too far

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

25.8

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Flue gas oxygen analyzer AI-469 with low alarm.

None

Other LOPA Ratio

1.00E-01

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSLL-1730

SIS Function:

Interlock PSLL-1730 that isolates the fuel gas from the heaters on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1347A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

Process Design

1 1.00E-01

1.00E-02

Blast doors.

BPCS

None

PSV

None

Op Response

Flue gas oxygen analyzer AI-469 with low alarm.

1.00E-01 None

Other LOPA Ratio

1.00E-04

None

Person Present Independent Protection Layers

25.8

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSLL-1730

SIS Function:

Interlock PSLL-1730 that isolates the fuel gas from the heaters on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in mediumsized area and potential environmental impacts in a small area

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Carryover of liquid as a result of high level- fuel gas KO drum.

Intermittent Hazard Ignition Probability

1 1.00E-01

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pilot gas pressure indication PI-855 with low pressure alarm

1.00E-01 None

Other

Recommendation

1.00E-04

None

Person Present

LOPA Ratio

Com:

None

Vulnerability Factors

Independent Protection Layers

25.11

Safety:

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No: SIS Function:

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in mediumsized area and potential environmental impacts in a small area

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Low fuel pressure due to control valve FV- 1 1.00E-01 851 closing to far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

25.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pilot gas pressure indication PI-855 with low pressure alarm

None

Other LOPA Ratio Recommendation

1.00E-01

Safety:

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No: SIS Function:

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in mediumsized area and potential environmental impacts in a small area

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Local control valve PCV-1348 closing too 1 1.00E-01 far

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

25.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pilot gas pressure indication PI-855 with low pressure alarm

None

Other LOPA Ratio

1.00E-01

Safety:

Recommendation

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1724

SIS Function:

Interlock PSLL-1724 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in mediumsized area and potential environmental impacts in a small area

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1346A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pilot gas pressure indication PI-855 with low pressure alarm

Other LOPA Ratio Recommendation

1.00E-04

None

Person Present Independent Protection Layers

25.11

1.00E-01 None

Safety:

0.100

Env:

0.010

Com:

0.01

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No: SIS Function:

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in mediumsized area and potential environmental impacts in a small area

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

High pressure transient from the fuel gas 1 1.00E-01 supply header.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

25.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pilot gas pressure indication PI-855 with low pressure alarm

None

Other LOPA Ratio Recommendation

None

Safety:

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No: SIS Function:

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in mediumsized area and potential environmental impacts in a small area

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low fuel pressure due to isolation valve XV-1347A or B being closed.

Intermittent Hazard Ignition Probability

1 1.00E-01

1 Present all the Time

Process Design

None

BPCS

None

PSV

None

Op Response

Pilot gas pressure indication PI-855 with low pressure alarm

1.00E-01 None

Other

Recommendation

1.00E-04

None

Person Present

LOPA Ratio

Com:

None

Vulnerability Factors

Independent Protection Layers

25.11

Safety:

0.010

Env:

0.010

Com:

0.01

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No: SIS Function:

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Overflow of liquid to the booster and/or recycle compressors, resulting in mechanical damage, potentially leading to a release of hydrogen and hydrocarbon at the compressors that could cause a fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-05

Env:

1.00E-04

Com:

1.00E-05

Low/no flow- naphtha from the product 1 1.00E-01 separator to the chloride scrubber due to control valve LV-122 closing too far and/or the pump tripping off.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

28.1

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

High level alarm LH-257.

None

Other LOPA Ratio

Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

14. Ensure that high level alarm LH-257 is on a routine testing schedule. 15. Ensure that Interlock LSHH-256 that shuts down the compressors on high high level is designed for SIL 1. 16. Evaluate if Interlock LSHH-256 should be designed for Environmental EIL 2 and Commercial CIL 3.

SIS No:

LSHH-256

SIS Function:

Interlock LSHH-256 that shuts down the compressors on high high level.

Required SIL Level: 2

EIL Level:

2

CIL Level:

3

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Overflow of liquid to the booster and/or recycle compressors, resulting in mechanical damage, potentially leading to a release of hydrogen and hydrocarbon at the compressors that could cause a fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-05

Env:

1.00E-04

Low/no flow- chloride scrubber.

Com:

1.00E-05

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

28.1

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

High level alarm LH-257.

None None

Other LOPA Ratio

Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

See LOPA Recommendation 14 to ensure that high level alarm LH-257 is on a routine testing schedule. See LOPA Recommendation 15 ensure that Interlock LSHH-256 that shuts down the compressors on high high level is designed for SIL 2. See LOPA Recommendation 16 to evaluate if Interlock LSHH-256 should be designed for Environmental EIL 2 and Commercial CIL 2.

SIS No:

LHH-256; LSHH-256

SIS Function:

High-high level alarm LHH-256 and interlock LSHH-256 that shuts down the compressors on high-high level.

Required SIL Level: 2

EIL Level:

2

CIL Level:

3

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

28.1

Overflow of liquid to the booster and/or recycle compressors, resulting in mechanical damage, potentially leading to a release of hydrogen and hydrocarbon at the compressors that could cause a fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-05

Env:

1.00E-04

Com:

1.00E-05

Reverse flow- naphtha from the product 1 None separator to the chloride scrubber due to the pump tripping off. (This consequence was evaluated and Team agreed that it was not a credible scenario)

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

High level alarm LH-257.

None

Other LOPA Ratio

Safety:

Recommendation

0.000

Env:

0.000

Com:

0.00

See LOPA Recommendation 14 to ensure that high level alarm LH-257 is on a routine testing schedule. See LOPA Recommendation 15 ensure that Interlock LSHH-256 that shuts down the compressors on high high level is designed for SIL 2. See LOPA Recommendation 16 to evaluate if Interlock LSHH-256 should be designed for Environmental EIL 2 and Commercial CIL 2.

SIS No:

LSHH-256

SIS Function:

High-high level alarm LHH-256 and interlock LSHH-256 that shuts down the compressors on high-high level.

Required SIL Level: 3

EIL Level:

3

CIL Level:

4

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA)

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Release of hydrocarbon and/or hydrogen resulting in (a) a fire in the firebox, potentially causing structural damage (e.g., collapse of the heater stack) that may injure personnel and rupture process equipment in a medium-sized area around the heater, (b) a fire and/or explosion outside the heater that may injure personnel in a medium-sized area, and (c) environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Compressor tripping off.

1 1.00E-01

Intermittent Hazard

P&ID: 3165-1-50-013B Loop: F-0106

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

29.2

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.010

1.00E-04

Env:

0.001

Com:

0.00

17. Ensure that interlock FSLL-106 is designed for SIL 1.

SIS No:

FSLL-106

SIS Function:

Interlock FSLL-106 that isolates the fuel gas to the charge heater and interheaters on low low recycle hydrogen flow.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Release of hydrocarbon and/or hydrogen resulting in (a) a fire in the firebox, potentially causing structural damage (e.g., collapse of the heater stack) that may injure personnel and rupture process equipment in a medium-sized area around the heater, (b) a fire and/or explosion outside the heater that may injure personnel in a medium-sized area, and (c) environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Operator error, manual valve closed.

Intermittent Hazard

P&ID: 3165-1-50-013B Loop: F-0106

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

29.2

1 1.00E-01

None

BPCS

None

PSV

None

Op Response

None

Other

None Safety:

Recommendation

0.010

1.00E-04

1 1.00E-01

Process Design

LOPA Ratio

Com:

Env:

0.001

Com:

0.00

See LOPA Recommendation 17 to ensure that interlock FSLL-106 is designed for SIL 1.

SIS No:

FSLL-106

SIS Function:

Interlock FSLL-106 that isolates the fuel gas to the charge heater and interheaters on low low recycle hydrogen flow.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Release of hydrocarbon and/or hydrogen resulting in (a) a fire in the firebox, potentially causing structural damage (e.g., collapse of the heater stack) that may injure personnel and rupture process equipment in a medium-sized area around the heater, (b) a fire and/or explosion outside the heater that may injure personnel in a medium-sized area, and (c) environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Misdirected flow to the flare through emergency dump valve HV-258.

Intermittent Hazard

P&ID: 3165-1-50-013B Loop: F-0106

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

29.2

1 1.00E-01

None

BPCS

None

PSV

None

Op Response

None

Other

None Safety:

Recommendation

0.010

1.00E-04

1 1.00E-01

Process Design

LOPA Ratio

Com:

Env:

0.001

Com:

0.00

See LOPA Recommendation 17 to ensure that interlock FSLL-106 is designed for SIL 1.

SIS No:

FSLL-106

SIS Function:

Interlock FSLL-106 that isolates the fuel gas to the charge heater and interheaters on low low recycle hydrogen flow.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential loss of containment if the pressure exceeds the pressure rating of the equipment with a potential release of hydrogen that could result in a potential fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-05

Env:

1.00E-04

Manual valve closed.

Com:

1.00E-05

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

30.9

1 1.00E-01

Process Design

None

BPCS

None PSV-1157 or PSV-1150.

PSV

1.00E-02

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.100

Com:

0.01

18. Ensure that Interlock PDSHH-171 that shuts down compressor C-2A on high-high differential pressure between the suction and discharge of the first-stage and/or Interlock PDSHH-175 that shuts down compressor C2-B on high high differential pressure between the suction and discharge of the first stage are designed for SIL 1.

SIS No:

PHH-171; PDSHH-171

SIS Function:

High-high differential pressure alarm PHH-171 with Interlock PDSHH-171 that shuts down compressor C-2A on high-high differential pressure between the suction and discharge of the first-stage. High differential pressure alarm PH-174, high high differential pressure alarm PHH175 with Interlock PDSHH-175 that shuts down compressor C2-B on high high differential pressure between the suction and discharge of the first stage.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Overflow of liquid hydrocarbon to the second-stage of the booster compressor, potentially resulting in mechanical damage and release of hydrogen and hydrocarbon that could cause a fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-05

Env:

1.00E-04

Com:

1.00E-05

Bottoms line from the interstage KO drum 1 1.00E-01 to the depentanizer due to operator error -- manual valve closed.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

32.1

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

LH-178 high level alarm.

None

Level indication LC-723 with high level alarm. Other LOPA Ratio

None Safety:

Recommendation

0.001

Env:

0.001

Com:

0.00

19. Ensure that LH-178 is on a routine testing schedule. 20. Ensure that LSHH-179 that shuts down the booster compressor on high-high level is designed for SIL 1. 21. Evaluate if Interlock LSHH-179 should be designed for an Environmental EIL 2 and/or Commercial CIL 3.

SIS No:

LSHH-179

SIS Function:

LSHH-179 that shuts down the booster compressor on high-high level.

Required SIL Level: 2

EIL Level:

2

CIL Level:

3

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential loss of containment if the pressure exceeds the pressure rating of the equipment, potential release of hydrogen that could result in potential fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-05

Env:

1.00E-04

Manual valve closed

Com:

1.00E-05

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

33.8

1 1.00E-01

Process Design

None

BPCS

None

PSV

1.00E-02

PSV-1156R or PSV-1149R.

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.100

Env:

0.100

Com:

0.01

22. Ensure that PDSHH-173 that shuts down compressor C-2A on high-high differential pressure between the suction and discharge lines and/or PDSHH-177 that shuts down compressor C-2B on high-high differential pressure between the suction and discharge lines is designed for SIL 1.

SIS No:

PDSHH-173/177

SIS Function:

PDSHH-173 that shuts down compressor C-2A on high-high differential pressure between the suction and discharge lines; PDSHH-177 that shuts down compressor C-2B on high-high differential pressure between the suction and discharge lines.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Carryover of liquid hydrocarbon to the TDP Unit, potentially resulting in high level in the compressor suction drum (OSBL).

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Reverse flow due to booster compressor 1 1.00E-01 tripping off.

Intermittent Hazard

This scenario was revisited during the June 21 meeting.

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

39.1

1 1.00E-01

None

Process Design TDP Compressor Suction Drum (50C101) Level Control.

BPCS

1.00E-04

PSV

None None

Op Response

None

LSH-180 high level alarm.

None

Other LOPA Ratio

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 25 to confirm the level alarm for the TDP Compressor Suction Drum is independent of the level control valve and is on a routine testing schedule. See LOPA Recommendation 26 to ensure that LSH-180 high level alarm is on a routine testing schedule.

SIS No:

LSHH-181

SIS Function:

LSHH-181 that shuts down the booster compressor on high-high level.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Carryover of liquid hydrocarbon to the TDP Unit, potentially resulting in high level in the compressor suction drum (OSBL).

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Low/no flow - bottoms from the high 1 1.00E-01 pressure separator to the interstage KO drum due to operator error -- manual valve closed.

Intermittent Hazard

This scenario was revisited during the June 21 meeting.

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

39.1

1 1.00E-01

Process Design

None TDP Compressor Suction Drum (50C101) Level Control.

BPCS

1.00E-04

None None

PSV Op Response

LSH-180 high level alarm.

None

Other LOPA Ratio

None Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

25. Confirm the level alarm for the TDP Compressor Suction Drum is independent of the level control valve and is on a routine testing schedule. 26. Ensure that LSH-180 high level alarm is on a routine testing schedule.

SIS No:

LSHH-181

SIS Function:

LSHH-181 that shuts down the booster compressor on high-high level.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Carryover of liquid hydrocarbon to the Unibon Unit, potentially resulting in high level in the compressor suction drum (OSBL).

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Reverse flow due to booster compressor 1 1.00E-01 tripping off.

Intermittent Hazard

This scenario was revisited during the June 21 meeting.

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

39.1

1 1.00E-01

None

Process Design Unibon Compressor Suction Drum (13C1A/B) Level Control.

BPCS

1.00E-04

PSV

None None

Op Response

None

LSH-180 high level alarm.

None

Other LOPA Ratio

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 23 to confirm the level alarm for the Unibon Compressor Suction Drum (13C1A/B) is independent of the level control valve and is on a routine testing schedule. See LOPA Recommendation 24 to ensure that LSH-180 high level alarm is on a routine testing schedule.

SIS No:

LSHH-181

SIS Function:

LSHH-181 that shuts down the booster compressor on high-high level.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Carryover of liquid hydrocarbon to the Unibon Unit, potentially resulting in high level in the compressor suction drum (OSBL).

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Control valve LV-150 closing too far.

1 1.00E-01

Intermittent Hazard

This scenario was revisited during the June 21 meeting.

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

39.1

1 1.00E-01

Process Design

None Unibon Compressor Suction Drum (13C1A/B) Level Control.

BPCS

1.00E-04

None None

PSV Op Response

LSH-180 high level alarm.

None

Other LOPA Ratio

None Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

23. Confirm the level alarm for the Unibon Compressor Suction Drum (13C1A/B) is independent of the level control valve and is on a routine testing schedule. 24. Ensure that LSH-180 high level alarm is on a routine testing schedule.

SIS No:

LSHH-181

SIS Function:

LSHH-181 that shuts down the booster compressor on high-high level.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Tube failure in depentanizer reboiler trim heater (H-5) resulting in release of hydrocarbon that could result in (a) fire and/or explosion that may injure personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Low level, depentanizer.

Intermittent Hazard

P&ID:3165-1-50-021 Loop: F-0783, F-0784, F-0785, F-0786

None

Vulnerability Factors

Ignition Probability

None

None

BPCS

None

PSV

None

Op Response

None

Other

None Safety:

Recommendation

0.010

1.00E-04

1 1.00E-01

Process Design

LOPA Ratio

Com:

1 1.00E-01

Person Present Independent Protection Layers

49.2

Env:

0.001

Com:

0.00

27. Consider adding an additional alarm to indicate loss of hydrogen and hydrocarbon flow to (H-5) on each pass and ensure it is on a routine testing schedule. 28. Ensure that interlocks FSLL-783/784/785/786 are designed for SIL 1.

SIS No:

FSLL-783/784/785/786

SIS Function:

Interlocks FSLL-783/784/785/786 isolate the flue gas from the charge heater, interheaters, and depentanizer reboiler trim heater on low low flow.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Tube failure in depentanizer reboiler trim heater (H-5) resulting in release of hydrocarbon that could result in (a) fire and/or explosion that may injure personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Manual valve closed.

Intermittent Hazard

P&ID:3165-1-50-021 Loop: F-0783, F-0784, F-0785, F-0786

None

Vulnerability Factors

Ignition Probability

None

None

BPCS

None

PSV

None

Op Response

None

Other

None Safety:

Recommendation

0.010

1.00E-04

1 1.00E-01

Process Design

LOPA Ratio

Com:

1 1.00E-01

Person Present Independent Protection Layers

49.2

Env:

0.001

Com:

0.00

See LOPA Recommendation 27 to consider adding an additional alarm to indicate loss of hydrogen and hydrocarbon flow to (H-5) on each pass and ensure it is on a routine testing schedule. See LOPA Recommendation 28 to ensure that interlocks FSLL-783/784/785/786 are designed for SIL 1.

SIS No:

FSLL-783/784/785/786

SIS Function:

Interlocks FSLL-783/784/785/786 isolate the flue gas from the charge heater, interheaters, and depentanizer reboiler trim heater on low low flow.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Tube failure in depentanizer reboiler trim heater (H-5) resulting in release of hydrocarbon that could result in (a) fire and/or explosion that may injure personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Misdirected flow to the raffinate splitter bottom pump discharge line.

1 1.00E-01

Intermittent Hazard

P&ID:3165-1-50-021 Loop: F-0783, F-0784, F-0785, F-0786

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

49.2

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.010

1.00E-04

Env:

0.001

Com:

0.00

See LOPA Recommendation 27 to consider adding an additional alarm to indicate loss of hydrogen and hydrocarbon flow to (H-5) on each pass and ensure it is on a routine testing schedule. See LOPA Recommendation 28 to ensure that interlocks FSLL-783/784/785/786 are designed for SIL 1.

SIS No:

FSLL-783/784/785/78

SIS Function:

Interlocks FSLL-783/784/785/786 isolate the flue gas from the charge heater, interheaters, and depentanizer reboiler trim heater on low low flow.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Tube failure in depentanizer reboiler trim heater (H-5) resulting in release of hydrocarbon that could result in (a) fire and/or explosion that may injure personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Control valves FV-783-786 closing too far. 1 1.00E-01

Intermittent Hazard

P&ID:3165-1-50-021 Loop: F-0783, F-0784, F-0785, F-0786

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

49.2

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.010

1.00E-04

Env:

0.001

Com:

0.00

See LOPA Recommendation 27 to consider adding an additional alarm to indicate loss of hydrogen and hydrocarbon flow to (H-5) on each pass and ensure it is on a routine testing schedule. See LOPA Recommendation 28 to ensure that interlocks FSLL-783/784/785/786 are designed for SIL 1.

SIS No:

FSLL-783/784/785/78

SIS Function:

Interlocks FSLL-783/784/785/786 isolate the flue gas from the charge heater, interheaters, and depentanizer reboiler trim heater on low low flow.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Tube failure in depentanizer reboiler trim heater (H-5) resulting in release of hydrocarbon that could result in (a) fire and/or explosion that may injure personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Pump tripping off.

Intermittent Hazard

P&ID:3165-1-50-021 Loop: F-0783, F-0784, F-0785, F-0786

None

Vulnerability Factors

Ignition Probability

None

None

BPCS

None

PSV

None

Op Response

None

Other

None Safety:

Recommendation

0.010

1.00E-04

1 1.00E-01

Process Design

LOPA Ratio

Com:

1 1.00E-01

Person Present Independent Protection Layers

49.2

Env:

0.001

Com:

0.00

See LOPA Recommendation 27 to consider adding an additional alarm to indicate loss of hydrogen and hydrocarbon flow to (H-5) on each pass and ensure it is on a routine testing schedule. See LOPA Recommendation 28 to ensure that interlocks FSLL-783/784/785/786 are designed for SIL 1.

SIS No:

FSLL-783/784/785/78

SIS Function:

Interlocks FSLL-783/784/785/786 isolate the flue gas from the charge heater, interheaters, and depentanizer reboiler trim heater on low low flow.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Tube failure in depentanizer reboiler trim heater (H-5) resulting in release of hydrocarbon that could result in (a) fire and/or explosion that may injure personnel in a medium-sized area and (b) environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Plugged strainer in the pump suction line. 1 1.00E-01 P&ID:3165-1-50-021 None Loop: F-0783, F-0784, F-0785, F-0786

Vulnerability Factors

Ignition Probability

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.010

1.00E-04

None

Person Present Independent Protection Layers

49.2

Env:

0.001

Com:

0.00

See LOPA Recommendation 27 to consider adding an additional alarm to indicate loss of hydrogen and hydrocarbon flow to (H-5) on each pass and ensure it is on a routine testing schedule. See LOPA Recommendation 28 to ensure that interlocks FSLL-783/784/785/786 are designed for SIL 1.

SIS No:

FSLL-783/784/785/78

SIS Function:

Interlocks FSLL-783/784/785/786 isolate the flue gas from the charge heater, interheaters, and depentanizer reboiler trim heater on low low flow.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Manual valve closed.

Com:

1.00E-04

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

50.8

Process Design

1 1.00E-01

Blast doors.

1.00E-02

BPCS

None

PSV

None

Op Response

Flue gas analyzer AI-738 with low alarm.

None

Other LOPA Ratio

1.00E-01

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSLL-1350

SIS Function:

Interlock PSLL-1350 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Control valve FV-877 closing too far.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

50.8

Process Design

1 1.00E-01

Blast doors.

1.00E-02

BPCS

None

PSV

None

Op Response

Flue gas analyzer AI-738 with low alarm.

None

Other LOPA Ratio

1.00E-01

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSLL-1350

SIS Function:

Interlock PSLL-1350 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low pressure - fuel gas header

Com:

1.00E-04

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

50.8

Process Design

1 1.00E-01

Blast doors.

1.00E-02

BPCS

None

PSV

None

Op Response

Flue gas analyzer AI-738 with low alarm.

1.00E-01

Pressure indication PI-874 with low pressure alarm None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSLL-1350

SIS Function:

Interlock PSLL-1350 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, potential inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1360A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

Process Design

1 1.00E-01

Blast doors.

1.00E-02

BPCS

None

PSV

None

Op Response

Flue gas analyzer AI-738 with low alarm.

1.00E-01 None

Other LOPA Ratio

1.00E-04

None

Person Present Independent Protection Layers

50.8

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSLL-1350

SIS Function:

Interlock PSLL-1350 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Local control valve PCV-1371 closing too 1 1.00E-01 far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

50.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-873 with low pressure alarm

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1351

SIS Function:

Interlock PSLL-1351 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Carryover of liquid as a result of high level- fuel gas KO drum due to operator error -- failure to drain liquids from the drum when needed

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

50.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-873 with low pressure alarm

Other LOPA Ratio

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1351

SIS Function:

Interlock PSLL-1351 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Manual valve closed.

Com:

1.00E-04

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

50.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-873 with low pressure alarm

Other LOPA Ratio

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1351

SIS Function:

Interlock PSLL-1351 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Total loss of combustion air due to stack 1 1.00E-01 damper closing too far. Total loss of combustion air due to combustion air registers closed too far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

50.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-873 with low pressure alarm

Other LOPA Ratio

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1351

SIS Function:

Interlock PSLL-1351 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1359A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-873 with low pressure alarm

Other LOPA Ratio

1.00E-04

None

Person Present Independent Protection Layers

50.11

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1351

SIS Function:

Interlock PSLL-1351 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

High pressure transient from the fuel gas 1 1.00E-01 supply header

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

50.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-873 with low pressure alarm

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1351

SIS Function:

Interlock PSLL-1351 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Low fuel pressure due to control valve FV-1 1.00E-01 877 closing too far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

50.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-873 with low pressure alarm

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1351

SIS Function:

Interlock PSLL-1351 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low fuel pressure due to isolation valve XV-1360A or B is closed.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

50.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-873 with low pressure alarm

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1351

SIS Function:

Interlock PSLL-1351 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Manual valve closed

Com:

1.00E-04

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

60.8

Process Design

1 1.00E-01

Blast doors.

1.00E-02

BPCS

None

PSV

None

Op Response

Flue gas analyzer AI-760 with low alarm.

1.00E-01

Pressure indication PI-879 with low pressure alarm. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSLL-1361

SIS Function:

Interlock PSLL-1361 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Control valve FV-822 closing too far

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

60.8

Process Design

1 1.00E-01

Blast doors.

1.00E-02

BPCS

None

PSV

None

Op Response

Flue gas analyzer AI-760 with low alarm.

1.00E-01

Pressure indication PI-879 with low pressure alarm. None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSLL-1361

SIS Function:

Interlock PSLL-1361 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low pressure - fuel gas header

Com:

1.00E-04

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

60.8

Process Design

1 1.00E-01

Blast doors.

1.00E-02

BPCS

None

PSV

None

Op Response

Flue gas analyzer AI-760 with low alarm.

None

Other LOPA Ratio

1.00E-01

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSLL-1361

SIS Function:

Interlock PSLL-1361 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Burner/pilot flameout, inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

Intermittent Hazard

Isolation valve XV-1372A or B is closed. 1 1.00E-01 None

Vulnerability Factors

Ignition Probability

Process Design

1 1.00E-01

Blast doors.

1.00E-02

BPCS

None

PSV

None

Op Response

Flue gas analyzer AI-760 with low alarm.

1.00E-01 None

Other LOPA Ratio

1.00E-04

None

Person Present Independent Protection Layers

60.8

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSLL-1361

SIS Function:

Interlock PSLL-1361 that isolates the fuel gas from the heater on low-low fuel gas pressure.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Local control valve PCV-1373 closing too 1 1.00E-01 far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

60.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-878 with low pressure alarm

Other LOPA Ratio

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1362

SIS Function:

Interlock PSLL-1362 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Carryover of liquid as a result of high level - fuel gas KO drum failure to drain liquids from the drum when needed.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

60.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-878 with low pressure alarm

Other LOPA Ratio

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1362

SIS Function:

Interlock PSLL-1362 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Low fuel pressure due to operator error -- 1 1.00E-01 manual valve closed.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

60.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-878 with low pressure alarm

Other LOPA Ratio

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1362

SIS Function:

Interlock PSLL-1362 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Total loss of combustion air due to stack 1 1.00E-01 damper closing too far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

60.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-878 with low pressure alarm

Other LOPA Ratio

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1362

SIS Function:

Interlock PSLL-1362 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Isolation valve XV-1367A or B is closed

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

60.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-878 with low pressure alarm

None

Other LOPA Ratio

None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1362

SIS Function:

Interlock PSLL-1362 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

High pressure transient from the fuel gas 1 1.00E-01 supply header

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

60.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-878 with low pressure alarm

Other LOPA Ratio

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1362

SIS Function:

Interlock PSLL-1362 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Com:

1.00E-04

Low fuel pressure due to control valve FV-1 1.00E-01 882 closing too far.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

60.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-878 with low pressure alarm

Other LOPA Ratio

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1362

SIS Function:

Interlock PSLL-1362 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Low fuel pressure due to isolation valve XV- 1372A or B is closed.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

60.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-878 with low pressure alarm

Other LOPA Ratio

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1362

SIS Function:

Interlock PSLL-1362 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Inability to ignite the burners following a flameout, resulting in a high concentration of combustibles in the firebox, potential for an explosion that could result in potential injury to personnel in a medium-sized area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-04

Env:

1.00E-04

Total loss of combustion air due to combustion air registers closed too far.

Intermittent Hazard

Com:

1.00E-04

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

60.11

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Pressure indication PI-878 with low pressure alarm

Other LOPA Ratio

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 11 to review the revalidation from MOC to change pilot gas to Purchased Natural Gas.

SIS No:

PSLL-1362

SIS Function:

Interlock PSLL-1362 that isolates the pilot gas from the heater on low-low pilot gas pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Low/no seal oil flow to the compressor, damage to the compressor, potentially leading to a release of hydrogen that could result in potential fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

1.00E-05

Env:

1.00E-04

Com:

Initiating Cause

Control valve LV-1437 closing too far.

1 1.00E-01

Intermittent Hazard

This scenario was revisited during the June 21 meeting.

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

72.2

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

Recommendation

0.001

1.00E-04

Env:

0.001

Com:

0.00

29. Consider bringing a low seal oil level alarm into DCS (independent of LV-1437). 30. Ensure that Interlock LSLL-38 that shuts down the compressor and prevents restart on low-low level in the overhead seal oil tank and/or Interlock LSL-57 that starts the auxiliary lube oil pump on low level in the overhead seal oil tank are designed for SIL 2. 31. Evaluate if Interlock LSLL-38 and/or LSL-57 should be designed for Environmental EIL 2 and Commercial CIL 3.

SIS No:

LSLL-38; LSL-57

SIS Function:

Interlock LSLL-38 that shuts down the compressor and prevents restart on low-low level in the overhead seal oil tank. Interlock LSL-57 that starts the auxiliary lube oil pump on low level in the overhead seal oil tank.

Required SIL Level: 2

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Low/no seal oil flow to the compressor, damage to the compressor, potentially leading to a release of hydrogen that could result in potential fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

1.00E-05

Env:

1.00E-04

Initiating Cause

Manual valve closed.

Intermittent Hazard

This scenario was revisited during the June 21 meeting.

None

Vulnerability Factors

Ignition Probability

None

None

BPCS

None

PSV

None Local low level alarms LAL-57/58. Local low-low level alarm LALL-38

Other LOPA Ratio

1.00E-01 None

Safety:

Recommendation

1.00E-04

1 1.00E-01

Process Design

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

72.2

0.010

Env:

0.010

Com:

0.01

See Recommendation 29 to consider bringing a low seal oil level alarm into DCS (independent of LV-1437). See Recommendation 30 to ensure that Interlock LSLL-38 that shuts down the compressor and prevents restart on low-low level in the overhead seal oil tank and/or Interlock LSL-57 that starts the auxiliary lube oil pump on low level in the overhead seal oil tank are designed for SIL 2. See Recommendation 31 to evaluate if Interlock LSLL-38 and/or LSL-57 should be designed for Environmental EIL 2 and Commercial CIL 3.

SIS No:

LSLL-38; LSL-57

SIS Function:

Interlock LSLL-38 that shuts down the compressor and prevents restart on low-low level in the overhead seal oil tank. Interlock LSL-57 that starts the auxiliary lube oil pump on low level in the overhead seal oil tank.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Damage to the compressor, potentially leading to a release of hydrogen that could result in potential fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Filter plugging.

Intermittent Hazard

This scenario was revisited during the June 21 meeting.

None

Vulnerability Factors

Ignition Probability

None

None

BPCS

None

PSV

None None

PAL-33 low pressure alarm.

Other LOPA Ratio

None Safety:

Recommendation

1.00E-04

1 1.00E-01

Process Design

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

72.9

0.010

Env:

0.001

Com:

0.00

32. Ensure that PAL-33 low pressure alarm is on a routine testing schedule. 33. Ensure that Interlock Interlock PSLL-32 shuts down compressor on low lube oil pressure is designed for SIL 1. 34. Evaluate if Interlock PSL-40 should be designed for Environmental EIL 2 and Commercial CIL3.

SIS No:

PSL-40

SIS Function:

Interlock PSL-40 that starts the spare pump on low lube oil pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Damage to the compressor, potentially leading to a release of hydrogen that could result in potential fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Manual valve closed.

Intermittent Hazard

This scenario was revisited during the June 21 meeting.

None

Vulnerability Factors

Ignition Probability

None

None

BPCS

None

PSV

None None

PAL-33 low pressure alarm.

Other LOPA Ratio

1.00E-04

1 1.00E-01

Process Design

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

72.9

None Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See Recommendation 32 to ensure that PAL-33 low pressure alarm is on a routine testing schedule. See Recommendation 33 to ensure that Interlock Interlock PSLL-32 shuts down compressor on low lube oil pressure is designed for SIL 1. See Recommendation 34 evaluate if Interlock PSL-40 should be designed for Environmental EIL 2 and Commercial CIL3.

SIS No:

PSLL-32

SIS Function:

Interlock PSLL-32 shuts down compressor on low lube oil pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Damage to the compressor, potentially leading to a release of hydrogen that could result in potential fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Lube/seal oil pump tripping off.

Intermittent Hazard

This scenario was revisited during the June 21 meeting.

None

Vulnerability Factors

Ignition Probability

None

None

BPCS

None

PSV

None None

PAL-33 low pressure alarm.

Other LOPA Ratio

None Safety:

Recommendation

1.00E-04

1 1.00E-01

Process Design

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

72.9

0.010

Env:

0.001

Com:

0.00

See Recommendation 32 to ensure that PAL-33 low pressure alarm is on a routine testing schedule. See Recommendation 33 to ensure that Interlock Interlock PSLL-32 shuts down compressor on low lube oil pressure is designed for SIL 1. See Recommendation 34 evaluate if Interlock PSL-40 should be designed for Environmental EIL 2 and Commercial CIL3.

SIS No:

PSL-40

SIS Function:

Interlock PSL-40 that starts the spare pump on low lube oil pressure.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Damage to the compressor, potentially leading to a release of hydrogen that could result in potential fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Com:

Initiating Cause

Low level in the lube oil reservoir -- failure 1 1.00E-01 to fill the lube oil tank

Intermittent Hazard

This scenario was revisited during the June 21 meeting.

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

73.8

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Low lube oil pressure alarm PAL-77/78.

Other LOPA Ratio

1.00E-04

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 35 to ensure that low lube oil pressure alarm PAL-77/78 is on a routine testing schedule. See LOPA Recommendation 36 ensure Interlock PSL-79/80 that shuts down Compressor is designed for SIL 1. See LOPA Recommendation 37 to evaluate if PSL-77 should be designed for Environmental EIL 2 and Commercial CIL 2.

SIS No:

PSL-77/78

SIS Function:

Low lube oil pressure alarm PAL-77/78 (local compressor panel and TDC) located on C-2B with interlock PSL-79/80 that shuts down the Compressor.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Damage to the compressor, potentially leading to a release of hydrogen that could result in potential fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Auxiliary lube oil pumps tripping off.

Intermittent Hazard

This scenario was revisited during the June 21 meeting.

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

73.8

1 1.00E-01

None

BPCS

None

PSV

None Low lube oil pressure alarm PAL-77/78.

None None

Other LOPA Ratio

1.00E-04

1 1.00E-01

Process Design

Op Response

Com:

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 35 to ensure that low lube oil pressure alarm PAL-77/78 is on a routine testing schedule. See LOPA Recommendation 36 ensure Interlock PSL-79/80 that shuts down Compressor is designed for SIL 1. See LOPA Recommendation 37 to evaluate if PSL-77 should be designed for Environmental EIL 2 and Commercial CIL 2.

SIS No:

PSL-77/78

SIS Function:

Low lube oil pressure alarm PAL-77/78 (local compressor panel and TDC) located on C-2B with interlock PSL-79/80 that shuts down the Compressor.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Damage to the compressor, potentially leading to a release of hydrogen that could result in potential fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Filters plugging.

Intermittent Hazard

This scenario was revisited during the June 21 meeting.

None

Vulnerability Factors

Ignition Probability

None

None

BPCS

None

PSV

None Low lube oil pressure alarm PAL-77/78.

Other LOPA Ratio

1.00E-03

1 1.00E-01

Process Design

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

73.8

None None

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.01

35. Ensure that low lube oil pressure alarm PAL-77/78 is on a routine testing schedule. 36. Ensure Interlock PSL-79/80 that shuts down Compressor is designed for SIL 1. 37. Evaluate if PSL-77 should be designed for Environmental EIL 2 and Commercial CIL 2.

SIS No:

PSL-77/78

SIS Function:

Low lube oil pressure alarm PAL-77/78 (local compressor panel and TDC) located on C-2B with interlock PSL-79/80 that shuts down the Compressor.

Required SIL Level: 1

EIL Level:

2

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Damage to the compressor, potentially leading to a release of hydrogen that could result in potential fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

1.00E-04

Env:

1.00E-04

Initiating Cause

Lube oil pump stops.

Intermittent Hazard

This scenario was revisited during the June 21 meeting.

None

Vulnerability Factors

Ignition Probability

None

None

BPCS

None

PSV

None Low lube oil pressure alarm PAL-77/78.

None None

Other LOPA Ratio

1.00E-04

1 1.00E-01

Process Design

Op Response

Com:

1 1.00E-01

Person Present Independent Protection Layers

73.8

Safety:

Recommendation

0.010

Env:

0.001

Com:

0.00

See LOPA Recommendation 35 to ensure that low lube oil pressure alarm PAL-77/78 is on a routine testing schedule. See LOPA Recommendation 36 ensure Interlock PSL-79/80 that shuts down Compressor is designed for SIL 1. See LOPA Recommendation 37 to evaluate if PSL-77 should be designed for Environmental EIL 2 and Commercial CIL 2.

SIS No:

PSL-77/78

SIS Function:

Low lube oil pressure alarm PAL-77/78 (local compressor panel and TDC) located on C-2B with interlock PSL-79/80 that shuts down the Compressor.

Required SIL Level: 1

EIL Level:

2

CIL Level:

2

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Damage to the compressor, potentially leading to a release of hydrogen that could result in potential fire and/or explosion that may injure personnel in a large area and potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

0.00E+00

Env:

1.00E-03

Low level in the jacket water reservoir

Intermittent Hazard

Com:

1.00E-03

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

73.12

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Low pressure alarm PAL-143 (local compressor panel and TDC).

None

High jacket water discharge temperature alarms TAH-85/86/87/88/89/90/91/92 (local compressor panel and TDC) located on the first-stage compressor. None

Other LOPA Ratio

Safety:

Recommendation

1.000

Env:

0.010

Com:

0.01

38. Ensure that jacket water discharge temperature alarms TAH85/86/87/88/89/90/91/92 (local compressor panel and TDC) located on the first-stage compressor are on a routine testing schedule. 39. Evaluate if TSHH-107/108/109/110 that shut down the compressor and prevent compressor restart if there is a high-high gas discharge temperature from the secondstage should be designed for EIL 1 and CIL 1.

SIS No:

TSHH-107/108/109/110

SIS Function:

TSHH-107/108/109/110 that shut down the compressor and prevent compressor restart if there is a high-high gas discharge temperature from the first-stage

Required SIL Level: 0

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Damage to the compressor, potential flaring.

Target Frequency

Safety:

Initiating Cause

0.00E+00

Env:

1.00E-03

Pump tripping off.

Com:

1.00E-03

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

73.12

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Low pressure alarm PAL-143 (local compressor panel and TDC).

None

High jacket water discharge temperature alarms TAH-85/86/87/88/89/90/91/92 (local compressor panel and TDC) located on the first-stage compressor. None

Other LOPA Ratio

Safety:

Recommendation

1.000

Env:

0.010

Com:

0.01

See LOPA Recommendation 38 to ensure that jacket water discharge temperature alarms TAH-85/86/87/88/89/90/91/92 (local compressor panel and TDC) located on the first-stage compressor are on a routine testing schedule. See LOPA Recommendation 39 to evaluate if TSHH-107/108/109/110 that shut down the compressor and prevent compressor restart if there is a high-high gas discharge temperature from the second-stage should be designed for EIL 1 and CIL 1.

SIS No:

TSHH-107/108/109/110

SIS Function:

TSHH-107/108/109/110 that shut down the compressor and prevent compressor restart if there is a high-high gas discharge temperature from the second-stage.

Required SIL Level: 0

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

High level in vent drum No. 3 or 4, potentially leading to plugging of the flow orifice in the off-gas line, resulting in high pressure - vent drum, potential loss of containment if the pressure exceeds the pressure rating of the equipment, potential release of catalyst, nitrogen, and/or hydrogen that could result in potential fire and/or explosion and thermal burn hazard that may injure personnel in a medium-sized area, potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-03

Env:

1.00E-02

Sequence valves BV-4 or 15 opens too soon or inadvertently opened.

Intermittent Hazard

Com:

1.00E-02

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

76.3

1 1.00E-01

None

Process Design Master controller verifies valve positions and shuts down the CCR if verification is not obtained.

BPCS

1.00E-01

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

1.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

FSH-318; FSH-308

SIS Function:

FSH-318 that shuts down the CCR on high off-gas flow from vent drum No. 3; FSH-308 that shuts down the CCR on high off-gas flow from vent drum No. 4

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential hydrogen carry through into the regenerator, resulting in formation of an explosive mixture that could cause a fire and/or explosion that may injure personnel in a medium-sized area, potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-02

Env:

1.00E-02

Nitrogen purging in lock hopper No. 1 is inadequate.

Intermittent Hazard

Com:

1.00E-02

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

76.24

Process Design

1 1.00E-01

3 separate nitrogen purge cycles are included in the PLC logic.

1.00E-01

BPCS

None

PSV

None

Op Response

None

Master verify alarm.

None

Other LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSH-305-1/305-2

SIS Function:

FSL-304 that stops the purge cycle timer on low nitrogen flow to lock hopper No. 1; PSH-305-1/305-2 that shutdown the CCR if purge pressure permissives are not net.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential backflow of hot combustion products into the Disengaging Hopper from the regenerator, resulting in high temperature in the Disengaging Hopper.

Target Frequency

Safety:

Initiating Cause

1.00E-02

Env:

1.00E-02

Low catalyst level occurs in the Disengaging Hopper.

Com:

1.00E-03

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

77.3

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

1.000

Env:

0.100

Com:

0.01

Recommendation

SIS No:

PSL-354

SIS Function:

PSL-354 that shuts down the regenerator on low differential pressure between the disengaging hopper and the regenerator.

Required SIL Level: 0

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential backflow of hot combustion products into the disengaging hopper from the regenerator, resulting in high temperature in the disengaging hopper, potential loss of containment if the temperature exceeds the temperature limit of the equipment, potential release of nitrogen and/or catalyst that could result in a thermal burn hazard that may injure personnel in a small area, potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-02

Env:

1.00E-02

Loss of nitrogen flow from the lift gas blower occurs.

Intermittent Hazard

Com:

1.00E-03

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

77.4

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Temperature indication TI-370 with high temperature alarm will give an early indication if there is an uncontrolled burn in the hopper.

1.00E-01

Other

Master verify alarm.

None

LOPA Ratio

Safety:

10.000

Env:

1.000

Com:

0.10

Recommendation

SIS No:

FSL-396

SIS Function:

FSL-396 that shuts down the regenerator on low nitrogen flow from the fines remover blower.

Required SIL Level: 0

EIL Level:

0

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential loss of containment if the temperature exceeds the temperature limit of the equipment.

Target Frequency

Safety:

Initiating Cause

1.00E-02

Env:

1.00E-02

High temperature occurs in the regeneration zone of the regenerator.

Intermittent Hazard

Com:

1.00E-02

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

78.1

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Temperature indication TI-552-554 with high temperature alarms

None

Other LOPA Ratio

1.00E-01

Safety:

10.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

TSHH-371; TSHL-365

SIS Function:

TSHH-371 that shuts down the regenerator on high-high regeneration vapor temperature; TSHL-365 that shuts down the regenerator on high chlorination gas temperature.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Failure to burn coke off of the catalyst in the regeneration zone, potentially leading to a high concentration of coke on the catalyst in the chlorination zone, which may cause an explosion that may injure personnel in a medium-sized area, potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-02

Env:

1.00E-02

Com:

1.00E-03

Low/no flow of regeneration vapor occurs. 1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

78.6

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Flow indication FC-379 with low flow alarm located on the air line to the regeneration blower.

None

Other LOPA Ratio

1.00E-01

Safety:

10.000

Env:

1.000

Com:

0.10

Recommendation

SIS No:

FSL-384

SIS Function:

FSL-384 located on the outlet of the regenerator heater that shuts down the regenerator on low regeneration vapor flow.

Required SIL Level: 0

EIL Level:

0

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high temperature in the regenerator due to localized hot spots, potential loss of containment if the temperature exceeds the temperature limit f the equipment, potential release of combustion gases, nitrogen, and/or catalyst that could result in a thermal burn hazard that may injure personnel in a small area, potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-02

Env:

1.00E-02

The chlorination blower trips off.

Com:

1.00E-02

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

78.8

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

1.000

Env:

0.100

Com:

0.10

Recommendation

SIS No:

FSL-363

SIS Function:

FSL-363 that shuts down the regenerator on low flow from the chlorination blower.

Required SIL Level: 0

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high temperature in the regenerator due to localized hot spots, potential loss of containment if the temperature exceeds the temperature limit f the equipment, potential release of combustion gases, nitrogen, and/or catalyst that could result in a thermal burn hazard that may injure personnel in a small area, potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-02

Env:

1.00E-02

The regeneration cooler blower trips off

Intermittent Hazard

Com:

1.00E-02

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

78.9

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

1.000

Env:

0.100

Com:

0.10

Recommendation

SIS No:

XSL-385

SIS Function:

XSL-385 that shuts down the CCR if the blower trips.

Required SIL Level: 0

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential high temperature in the regenerator chlorination zone due to localized hot spots, potential loss of containment if the temperature exceeds the temperature limit f the equipment, potential release of combustion gases, nitrogen, and/or catalyst that could result in a thermal burn hazard that may injure personnel in a small area, potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-02

Env:

1.00E-02

Low level occurs in the regenerator.

Intermittent Hazard

Com:

1.00E-02

1 1.00E-01

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

78.10

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

1.000

Env:

0.100

Com:

0.10

Recommendation

SIS No:

PDSL-354

SIS Function:

PDSL-354 that shuts down the regenerator on low differential pressure between the disengaging hopper and the regenerator

Required SIL Level: 0

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Formation of an explosive mixture in the regenerator, leading to an explosion that may injure personnel in a medium-sized area, potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-02

Env:

1.00E-02

Com:

1.00E-03

Loss of nitrogen purge occurs during the 1 1.00E-01 black burn mode.

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

78.17

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Master verify alarm.

None

Other LOPA Ratio

None Safety:

1.000

Env:

0.100

Com:

0.01

Recommendation

SIS No:

TSH-377; FSL-341

SIS Function:

TSH-377 that shuts down the air heaters on high temperature; FSL-341 that shuts down the CCR on low nitrogen purge gas flow.

Required SIL Level: 0

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Formation of an explosive mixture in the regenerator, leading to an explosion that may injure personnel in a medium-sized area, potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

0.00E+00

Env:

0.00E+00

No credible causes identified.

Com:

0.00E+00

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

80.9

Process Design

1 1.00E-01

3 separate nitrogen purge cycles are included in the PLC logic.

None

BPCS

None

PSV

None

Op Response

Master verify alarm.

None None

Other LOPA Ratio

1.000

Safety:

Env:

1.000

Com:

1.00

Recommendation

SIS No:

PSH-345-1/345-2; FSL-304

SIS Function:

PSH-345-1/345-2 that shutdown the CCR if purge pressure permissives are not met; FSL-304 that stops the purge cycle timer on low nitrogen flow to lock hopper No. 1

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Formation of an explosive mixture in the regenerator, leading to an explosion that may injure personnel in a medium-sized area, potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

1.00E-03

Env:

1.00E-02

Loss of nitrogen purge occurs to vent drum No. 2 off-gas line.

Com:

1.00E-02

1 1.00E-01

Intermittent Hazard

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

80.10

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

None

Other

None

LOPA Ratio

Safety:

0.100

Env:

0.100

Com:

0.10

Recommendation

SIS No:

FSL-394

SIS Function:

FSL-394 that shuts down the CDR on low-low nitrogen flow.

Required SIL Level: 1

EIL Level:

1

CIL Level:

1

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

80.11

Reverse flow occurs in the reduction zone, high temperature, potentially leading to release of hydrogen and catalyst if the temperature exceeds the temperature limit of the equipment, which may result in a fire and/or explosion that may injure personnel in a medium-sized area, potential environmental impacts in a small area. Team agrees there is no credible consequences identified.

Target Frequency

Safety:

0.00E+00

Env:

0.00E+00

Initiating Cause

Loss of hydrogen lift gas occurs.

Intermittent Hazard

The Team did not feel that this was a credible scenario.

None

Vulnerability Factors

Ignition Probability

None

Process Design

1 1.00E-01

3 separate nitrogen purge cycles are included in the PLC logic

1.00E-01

BPCS

None

PSV

None

Op Response

1.00E-01

Master verify alarm

None

Other LOPA Ratio

0.00E+00

1 1.00E-01

Person Present Independent Protection Layers

Com:

Safety:

1.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

FSL-346

SIS Function:

FSL-346 that shuts down the CCR on low hydrogen lift gas flow.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

80.21

Reverse flow occurs in the reduction zone, high temperature, potentially leading to release of hydrogen and catalyst if the temperature exceeds the temperature limit of the equipment, which may result in a fire and/or explosion that may injure personnel in a medium-sized area, potential environmental impacts in a small area. Team agrees there is no credible consequences identified.

Target Frequency

Safety:

0.00E+00

Env:

0.00E+00

Initiating Cause

Low level occurs in reactor No. 1 reduction zone.

Intermittent Hazard

The Team did not feel that this was a credible scenario.

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

1 1.00E-01

None

BPCS

None

PSV

None Level indication LI-309 with low level alarm

1.00E-01 None

Other LOPA Ratio

0.00E+00

1 1.00E-01

Process Design

Op Response

Com:

Safety:

1.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

LSL-309

SIS Function:

LSL-309 that shuts down the CCR on low level in the reduction zone of reactor No. 1

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

80.22

Potential oxygen carry through from lock hopper No. 2 into the reduction zone of reactor No. 1, resulting in formation of an explosive mixture in the regenerator, leading to an explosion that may injure personnel in a medium-sized area, potential environmental impacts in a small area. Team agrees there is no credible consequences identified.

Target Frequency

Safety:

0.00E+00

Env:

0.00E+00

Initiating Cause

Nitrogen purging in lock hopper No. 2 is inadequate.

Intermittent Hazard

The Team did not feel that this was a credible scenario.

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

Process Design

1 1.00E-01

3 separate nitrogen purge cycles are included in the PLC logic

1.00E-01 None

PSV

None 1.00E-01

Master verify alarm

None

Other LOPA Ratio

0.00E+00

1 1.00E-01

BPCS Op Response

Com:

1.000

Safety:

Env:

1.000

Com:

1.00

Recommendation

SIS No:

FSL-304; PSH-305-1/305-2

SIS Function:

FSL-304 that stops the purge cycle timer on low nitrogen flow to lock hopper No.1; PSH-305-1/305-2 that shutdown the CCR if purge pressure permissives are not met

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

80.29

High temperature, potentially leading to release of hydrogen and catalyst if the temperature exceeds the temperature limit of the equipment, which may result in a fire and/or explosion that may injure personnel in a medium-sized area, potential environmental impacts in a small area. Team agrees there is no credible consequences identified.

Target Frequency

Safety:

0.00E+00

Env:

0.00E+00

Com:

Initiating Cause

Reverse flow occurs in the reduction zone.1 1.00E-01

Intermittent Hazard

The Team did not feel that this was a credible scenario.

None

Vulnerability Factors

Ignition Probability

None

Person Present Independent Protection Layers

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Temperature indication TI-500 with high temperature alarm

Other LOPA Ratio

0.00E+00

1.00E-01 None

Safety:

1.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

TSH-311

SIS Function:

TSH-311 that shuts down the CCR on high reduction zone temperature.

Required SIL Level: 0

EIL Level:

0

CIL Level:

0

TOTAL Petrochemicals - LAYER OF PROTECTION ANALYSIS (LOPA) PHAName

PHA Ref.

TOTAL NHT REVAL

Consequence Description

Potential backflow of hydrogen into the nitrogen system from the nitrogen supply line to lock hopper No. 2, resulting in an explosion that may injure personnel in a small-sized area, potential environmental impacts in a small area.

Target Frequency

Safety:

Initiating Cause

0.00E+00

Env:

0.00E+00

Com:

Intermittent Hazard

Loss of nitrogen supply pressure occurs. 1 1.00E-01 This event requires multiple failures and is None not credible.

Vulnerability Factors

Ignition Probability

1 1.00E-01

Process Design

None

BPCS

None

PSV

None

Op Response

Low nitrogen flow switch FSL-341 that alarms and shuts down the CCR

1.00E-01 None

Other LOPA Ratio

0.00E+00

None

Person Present Independent Protection Layers

80.30

Safety:

1.000

Env:

1.000

Com:

1.00

Recommendation

SIS No:

FSL-344

SIS Function:

Low nitrogen flow switch FSL-344 that alarms and shuts down the CCR

Required SIL Level: 0

EIL Level:

0

CIL Level:

0