HAZOP.pdf

Project name: T2 Laboratories, Inc. Process: MCMT batch reactor Section: Reactor Item Study Node 1A Cooling coil

Process Parameters Flow

Deviations No

Possible Causes 1. Control valve fails closed 2. Plugged cooling coils (possibly due to mineral scale)

Possible Consequences 1. Loss of cooling, possible runaway and reactor overpressure 2. Loss of cooling, possible runaway and reactor overpressure

Action Required

3. Loss of cooling, possible runaway and reactor overpressure 4. Loss of cooling, possible runaway and reactor overpressure 5. Loss of cooling, possible runaway and reactor overpressure 1. Reactor cools, reactant concentration builds, possible runaway on heating 2. Reactor cools, reactant concentration builds, possible runaway on heating 1. Diminished cooling, possible runaway and reactor overpressure 2. Diminished cooling, possible runaway and reactor overpressure 3. Diminished cooling, possible runaway and reactor overpressure 1. Not possible here 1. Loss of cooling, possible runaway and reactor overpressure 2. Loss of cooling, possible runaway and reactor overpressure 1. None 1. Temperature rises, possible runaway and reactor overpressure 1. None - controller handles 1. Cooling system capacity limited, temperature increases, pressure increases

1. See 1A.2 2. Install check valve

1. Select valve to fail open 2. Install filter with maintenance procedure. Install cooling water flow meter and low flow alarm Install high temperature alarm ti alert operator 3. Check to monitor reliability of water service 4. Place controller on critical instrumentation list 5. See 1A.1 1. Instruct operators and update procedures 2. See 1A.4 1. See 1A.2 2. See 1A.2 3. Place valve on critical instrumentation list 1. None/check maintenance procedures

1B

High

1C

Low

1D 1E 1F

As well as Part of Reverse

1G 1H 1I 1J

Sooner than Later than Low High

3. Cooling water service failure 4. Controller fails and closes valve 5. Air pressure fails, closing valve 1. Control valve fails open 2. Control fails and opens valve 1. Partially plugged cooling line (possibly due to mineral scale) 2. Partial water source failure 3. Control valve fails to respond 1. Contamination of water supply 1. Covered under 1C 1. Failure of water source resulting in backflow 2. Backflow due to high backpressure 1. Cooling normally started early 1. Operator error 1. Low water supply temperature 1. Higher water supply temperature

Agitation

No More

1. Stirrer motor malfunction 1. Stirrer motor controller fails, resulting in high motor speed

1. No mixing, possible accumulation of unreacted materials 1. None

1. Interlock with feed line

Flow

No

1. Feed line is plugged

1. No reaction occurs

2. Feed line is cut

2. No reaction occurs

1. Operators should check/maintain feed line Reactant levels should constantly be checked 2. Operators should check/maintain feed line Operators should check that rotameters are calibrated prior to startup 1. Operators should check feed lines, reactant levels, and update maint. procedures 2. Operators should check feed lines, reactant levels, and update maint. procedures Proper cleanup consistent with safety and hazard information 1. Quality control checks on feed materials and products Operators should have general knowledge on hazardous side reactions of the reactant 1. Operators should check feed lines and update maintenance procedures 1. Quality control checks on feed materials and products Operators should have general knowledge on hazardous side reactions of the reactant 1. Operators should maintain surface area to volume ratio during scale up

2A 2B 3A

Temperature

Stirrer

Raw Materials Feed *Feed line consists of all materials besides sodium

1. Interlock between cooling flow and reactor feed 1. None 1. Install high flow alarm and/or cooling water high temp. alarm

3B

Low

1. Partially plugged feed line 2. Leaking feed line

1. Low reaction rate, low conversion 2. Low reaction rate, low conversion. Possible hazardous spill of feed materials.

3C

As well as

1. Contamination of feed, however very unlikely

1. Contaminated product, possible side reaction, low yield, unknown safety hazards

3D 3E

Sooner than Other than

1. Extra sodium added before adequate conversion is reached in the reactor 1. Something else besides typical reactants added

1. High reaction rate, higher temperatures. Possible overheating, runaway, overpressure 1. Contaminated product, possible side reaction, unknown safety hazards

Concentration

High

1. Improper scaling of reactor vessel

1. High reaction rate, higher temperatures. Possible overheating, runaway, overpressure

Temperature Pressure

Low High High

1. Hot oil system or cooling coil malfunction, lower concentration of feed, faulty temp. indicator 1. Hot oil system or cooling coil malfunction, higher concentration of feed, faulty temp. indicator 1. Hot oil system or cooling coil malfunction, higher concentration of feed, faulty pressure indicator

1. Low reaction rate, low conversion 1. High reaction rate, possible runaway and overpressure 1. Possible explosion

Volume

Low

1. Improper scaleup

1. High reaction rate, higher temperatures. Possible overheating, runaway, overpressure

1. Install temp. indicator controller, check reactant levels, and update maint. procedures 1. Operators should check all process parameters and update maintenance procedures 1. Operators should check all process parameters and update maintenance procedures Adequate pressure relief valve system should be in place 1. Operators should maintain surface area to volume ratio during scale up

Flow

High

1. Drain valve malfunction/fails open

1. Water can not properly cool system, causing reactor to overheat. Possible runaway, overpressure

1. Operators should check drainage lines prior to startup.

Rupture disk pressure limit

Wrong action

1. Operators unaware of pressure safety hazards and set rupture disk pressure too high

1. Overpressure relieved too late, causing explosion

6B

Training

Low

1. Neither owners previously worked with reactive processes, insufficient experience

1. Insufficient knowledge on controlling runaway reactions or more exothermic side reactions Increased severity in accidents Possible runaway and explosion

6C

Process hazard information

Unclear/none

1. Limited published information on MCMT

6D

Emergency cooling

Unclear/none

1. Insufficient experience, lacking sufficient safety training

6E

Venting hydrogen

Wrong action

1. Insufficient experience, lacking sufficient safety training

1. Hazards of product are not clearly identified. Employers can not adequately ensure safety Underestimation of full-scale batch temperatures 1. Backup source of water was not immediately available No emergency instructions to combat overheating of reactor when cooling line fails 1. Venting excess hydrogen to the atmosphere is extremely flammable and can cause severe damage

1. Operators should be aware of pressure specifications for each exothermic reaction Thorough scale up analysis to determine the amount of pressure to relieve in each reaction 1. Owners should have sufficient training in reactive processes to safely operate Owners should discuss/update emergency instructions and management of change clearly to employees Owners should be knowledgable on all safety hazards and minimize them Owners should perform preventative maintenance on all process nodes 1. Owners should thoroughly investigate the reaction in the lab with as many scenarios as possible Scaleup procedures should include reaction's behavior at higher temperatures 1. Owners should have sufficient training in reactive processes to safely operate Owners should discuss/update emergency instructions and management of change clearly to employees 1. Hydrogen gas should have been burned out instead of vented since it is flammable

3F 4A 4B 4C

Reactor

4D 5A

Drainage Valve

6A

Operating Instruction