GGS Operating Manual Vol 1
Short Description
GGS Operating Manual...
Description
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 2 of 275
EBLA GAS PROJECT
Document Title
GGS Operating Manual Vol #1
Document Number
00180-PCP-300-PD-MAN-12503-01
Type of Document
Manual
Rev
A1
Date
REVISION STATUS Description
Originator
08-10-09 Issue for Info-training RL Expiry Date of Procedure Life Cycle of review
APPROVAL Verified
AD
Approved
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 3 of 275
TABLE OF CONTENTS SECTION I 1.0 2.0 3.0 4.0 5.0 6.0 7.0
INTRODUCTION......................................................
ABBREVIATION................................................................................ TERMINOLOGY............................................................................... UNIT OF MEASUREMENT................................................................... OBJECTIVE OF OPERATION MANUAL.................................................. PREAMBLE..................................................................................... EMERGENCY SHUTDOWN.................................................................. INTENDED USERS............................................................................
SECTION II HEALTH, SAFETY AND ENVIRONMENT.......................... SECTION III HAZOPS & ROUNDS................................................. SECTION V GAS GATHERING STATION......................................... 1.0 INTRODUCTION............................................................ 1.1
OVERVIEW OF GAS GATHERING STATION.............................................
2.0
SPECIFIC SAFETY HAZARDS.............................................
2.1 2.2 2.2.1 2.2.2 2.2.3 2.3
GENERAL SAFETY PRECAUTIONS AND OPERATIONS.............................. HAZARDS IN HANDLING CHEMICALS................................................... Physical and Chemical Properties of TEG........................................... Physical and Chemical Properties of Methanol................................... Physical and Chemical Properties of Sodium Hypochlorite................... PPE REQUIREMENTS........................................................................
3.0
EQUIPMENT SPECIFICATION.............................................
3.1 METHANOL STORAGE TANK....................................................................... 3.2 METHANOL LOADING/UNLOADING PUMP............................................ 3.3 OPEN DRAIN NON-CONTAMINATED SUMP PUMP.................................... 3.4 OPEN DRAIN CONTAMINATED SUMP PUMP........................................... 3.5 CLOSED DRAIN DRUM...................................................................... 3.6 CLOSED DRAIN DRUM HEATER........................................................... 3.7 CLOSED DRAIN DRUM PUMP.............................................................. 3.8 LP PRODUCED WATER DISPOSAL PUMP...............................................
4.0
PROCESS AND CONTROL DESCRIPTION................................
4.1
PRODUCTION SEPARATOR.................................................................
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 4 of 275
4.1.1 Principle of Separation of Water from Oil in Separators...................... 4.1.2 Production Separator Controls......................................................... 4.2 FIELD GAS COMPRESSOR.................................................................. FIELD GAS COMPRESSOR SUCTION KNOCK-OUT DRUM........................................ FIELD GAS COMPRESSOR................................................................................ FIELD GAS COMPRESSOR AFTERCOOLER........................................................... 4.2.1 Process Description........................................................................ 4.2.2 Field Gas Compressor Controls......................................................... 4.3 CONDENSATE SYSTEM...................................................................... 4.3.1 PROCESS DESCRIPTION.................................................................... CONDENSATE PUMPS..................................................................................... CONDENSATE COALESCER............................................................................... CONDENSATE SOLIDS FILTER........................................................................... EARLY OPERATION CONDENSATE PUMPS........................................................... 4.3.2 Condensate System Control............................................................. 4.3.3 Condensate Coalescer Interface Level Control................................... 4.4 GAS DEHYDRATION SYSTEM.............................................................. 4.4.1 Process Description........................................................................ GAS DEHYDRATION COLUMN........................................................................... 4.4.2 Gas Dehydration Controls................................................................ 4.5 TEG REGENERATION SYSTEM............................................................ 4.5.1 Principle of TEG Regeneration System.............................................. GLYCOL CIRCULATION PUMPS.......................................................................... TEG BURNER AIR FAN..................................................................................... TEG MAKE-UP FILTER..................................................................................... TEG DRAIN VESSEL........................................................................................ TEG STRIPPING COLUMN................................................................................ TEG DRAIN PUMP.......................................................................................... TEG STORAGE TANK...................................................................................... TEG MAKE-UP PUMP...................................................................................... COLD LEAN/RICH GLYCOL HEAT EXCHANGER.................................................... HOT LEAN/RICH GLYCOL HEAT EXCHANGER...................................................... 4.5.2 Process Description........................................................................ 4.5.3 TEG Regenerator Controls............................................................... 4.6 TEG INCINERATOR SYSTEM............................................................... 4.6.1 TEG Incinerator Controls................................................................. 4.7 UTILITIES....................................................................................... 4.7.1 Plant Air System............................................................................. 4.7.2 Instrument Air System..................................................................... AIR COMPRESSOR.......................................................................................... INSTRUMENT AIR RECEIVER............................................................................
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 5 of 275
4.7.3 Nitrogen System............................................................................. NITROGEN RECEIVER..................................................................................... WET AIR RECEIVER........................................................................................ 4.7.4 Utility Water.................................................................................. UTILITY WATER TANK..................................................................................... BOREHOLE WATER PUMP................................................................................ UTILITY WATER PUMP.................................................................................... 4.7.5 Potable Water System..................................................................... POTABLE WATER TANKER UNLOADING PUMP..................................................... POTABLE WATER DISTRIBUTION PUMP.............................................................. 4.7.6 Diesel System................................................................................ 4.8 FUEL GAS SYTEM............................................................................ FUEL GAS KNOCK-OUT DRUM.......................................................................... FUELGAS HEATER.......................................................................................... FUELGAS SUPER HEATER................................................................................ 4.8.1 Fuel Gas System Control Description................................................ 4.9 FLARE SYSTEM............................................................................... FLARE KO DRUM........................................................................................... FLARE KO DRUM HEATER................................................................................ FLARE KNOCK-OUT DRUM BOOSTER PUMP........................................................ FLARE KO DRUM PUMP................................................................................... 4.9.1 Flare System Controls..................................................................... 4.10 PRODUCED WATER SYSTEM............................................................... 4.11 DRAIN SYSTEM................................................................................ 4.11.1 Open Drain System......................................................................... 4.11.2 Closed Drain system.....................................................................101 4.12 POWER GENERATOR SYSTEM...........................................................102
5.0
ELECTRICAL..............................................................106
5.1 5.1.1 5.1.2 5.1.3 5.1.4 5.2 5.3 5.4 5.5
ELECTRICAL SYSTEMS....................................................................107 Electrical System Controls.............................................................108 Electrical System Start-Up.............................................................110 System under Plant Normal Operating Condition..............................113 Electrical System – GTG Failure.....................................................114 EMERGENCY DIESEL GENERATOR SET...............................................118 MAIN HV SWITCHBOARD................................................................122 POWER TRANSFORMER..................................................................122 LV POWER DISTRIBUTION...............................................................123
6.0
INSTRUMENTATION......................................................127
6.1 6.2
INTEGRATED CONTROL AND SAFETY SYSTEM (ICSS)............................128 DISTRIBUTED CONTROL SYSTEM (DCS) – GGS....................................128
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 6 of 275
6.3 EMERGENCY SHUTDOWN SYSTEM (ESD) – GGS...................................132 Double Isolation Valves...............................................................................138
7.0
FIRE AND GAS............................................................141
7.1 7.2 7.3 7.4 7.5
FIRE & GAS – INTRODUCTION.........................................................142 FIRE DETECTORS..........................................................................143 ALERTING EQUIPMENT...................................................................143 FIRE ZONES..................................................................................146 HIGH-SENSITIVE SMOKE DETECTION SYSTEM (HSSD)..........................147
8.0
TELECOMMUNICATION..................................................150
8.1 8.2 8.3 8.3.1 8.4 8.4.1 8.5 8.6 8.7
TELECOM SUBSYSTEMS..................................................................151 SDH TRANSMISSION SYSTEM...........................................................151 TELEPHONE SYSTEM......................................................................152 Telephones..................................................................................152 RADIO SYSTEM.............................................................................152 Radio Tower.................................................................................153 ENVIRONMENTAL MONITORING SYSTEM............................................153 LOCAL AREA NETWORK..................................................................154 TELECOM SUPERVISORY SYSTEM......................................................154
9.0
PRODUCT SPECIFICATION..............................................155
9.1 9.2 9.3
GAS & CONDENSATE SPECIFICATION................................................156 GAS............................................................................................156 CONDENSATE...............................................................................156
10.0
PRE-REQUISITES FOR START-UP ACTIVITIES........................158
10.1 10.1.1 10.1.2 10.2 10.2.1 10.2.2 10.2.3 10.2.4 10.2.5 10.2.6 10.2.7
PRE-REQUISITE – SAFETY...............................................................159 Introduction................................................................................159 Safety.........................................................................................159 PRE-REQUISITE ACTIVITIES.............................................................159 Vessels and Pipelines....................................................................159 System Leak Testing and Purging....................................................160 HVAC in Control Room...................................................................160 Diesel and Chemicals....................................................................160 Checking of Functional Loop and Control Valves...............................160 Charging of Lubricants for Rotating Equipment................................160 L.P. Fuel Gas System.....................................................................161
11
START-UP OF UTILITIES AND OFF-SITE FACILITIES................162
11.1 11.1 11.2 11.3
SEQUENCE OF START-UP................................................................163 START-UP OF DIESEL SYSTEM..........................................................163 START-UP OF EMERGENCY POWER GENERATOR PACKAGE....................165 START-UP OF UTILITY WATER SYSTEM..............................................167
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 7 of 275
11.4 11.5 11.6 11.7 11.8 11.9 11.10 11.11 11.12 11.13 11.14 11.15
START-UP OF START-UP OF START-UP OF START-UP OF START-UP OF START-UP OF START-UP OF START-UP OF START-UP OF START-UP OF START-UP OF START-UP OF
POTABLE WATER SYSTEM.............................................168 PLANT AIR.................................................................169 INSTRUMENT AIR........................................................170 NITROGEN SYSTEM.....................................................171 FLARE SYSTEM...........................................................172 OPEN DRAIN SYSTEM..................................................173 CLOSED DRAIN SYSTEM...............................................174 FUEL GAS SYSTEM......................................................175 GAS TURBINE GENERATOR (GTG)..................................176 PRODUCED WATER SYSTEM..........................................182 METHANOL SYSTEM....................................................182 GLYCOL STORAGE AND TRANSFER SYSTEM.....................184
12.0
START-UP OF PROCESS PLANT........................................186
12.1 12.2 12.2.1 12.3 12.4 12.5 12.5.1 12.5.2 12.6 12.6.1 12.6.2 12.7 12.7.1 12.7 12.7.1
START-UP SEQUENCE OF GGS..........................................................187 PURGING OF HYDROCARBON SYSTEM..............................................188 Facility Leak Test with Pressurization of Feed Gas............................188 START-UP OF PRODUCTION SEPARATOR............................................189 START-UP OF THE CONDENSATE SYSTEM...........................................191 START-UP OF FIELD GAS COMPRESSOR (LP OPERATION)......................192 Purging of Feed Gas Compressor Circuit..........................................192 Start-up......................................................................................193 START-UP OF GAS DEHYDRATION SYSTEM.........................................199 Initial Start-up.............................................................................200 Start-up at normal conditions........................................................213 START-UP OF TEG INCINERATOR SYSTEM..........................................215 Pre-requisites before starting the TEG Incinerator...........................215 START-UP OF OILY WATER SYSTEM...................................................218 Line-up of Oily Water System.........................................................218
13.0
NORMAL OPERATION AND MONITORING.............................220
13.1 13.2 13.3
PRODUCTION SEPARATOR NORMAL OPERATION.................................221 GAS DEHYDRATION & TEG REGENERATION SYSTEM............................222 COMPRESSOR NORMAL OPERATION..................................................224
14.0
PLANT START-UP AFTER EMERGENCY SHUTDOWN................226
14.1 14.2 14.2.1 14.2.2 14.2.3 14.2.4 14.2.5
GENERAL EMERGENCY SHUTDOWN LEVELS - ESD1, ESD2 & ESD3.........227 PLANT START-UP AFTER ESD1 SHUTDOWN........................................227 Start-up of Utility Water Systems...................................................228 Start-up of Potable Water Systems.................................................228 Start-up of Plant Air System..........................................................229 Start-up of Instrument Air.............................................................230 Start-up of Nitrogen System..........................................................231
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 8 of 275
14.2.6 14.2.7 14.2.8 14.2.9 14.2.10 14.2.11 14.2.12 14.2.13 14.2.14 14.2.15 14.2.16 14.2.17 14.3 14.4 14.5
Start-up of Flare System...............................................................232 Start-up Open Drain System...........................................................232 Start-up Closed Drain System.........................................................233 Start-up of Fuel Gas System..........................................................233 Start-up of Gas Turbine Generator..................................................234 Start-up of Produced Water System................................................235 Start-up of Glycol Transfer System.................................................236 Start-up of Production Separator....................................................237 Start-up of the Condensate System................................................238 Start-up of Field Gas Compressor (LP Operation).............................239 Start-up of Gas-Dehydration..........................................................243 Line-up of Oily Water System.........................................................246 PLANT START-UP AFTER ESD2 SHUTDOWN........................................247 PLANT START-UP AFTER ESD3 SHUTDOWN........................................247 BLACK START-UP OF GGS...............................................................249
15.0 16.0
TROUBLESHOOTING OPERATION.....................................252 SHUTDOWN...............................................................260
16.1 16.2 16.2.1 16.2.2 16.2.3 16.3
PLANNED SHUTDOWN....................................................................261 EMERGENCY SHUTDOWN................................................................264 ESD Level-1 Shutdown...................................................................265 ESD Level-2: Process Shutdown......................................................265 ESD LEVEL-3: Unit/Equipment Shutdown.........................................267 DRAINING PHILOSOPHY/RECOVERY FOR START-UP.............................270
SECTION I
INTRODUCTION
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
1.0
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
ABBREVIATION
Acronym AC AMB API ATM BA BCS BDV BGU CCR CD CGR CNE CO2 CS CSO DB dB DBB DCS DE DP EDG ESD F&G FV FW FZ GC GGS GOR GTP H2S HC HH HMI HP HPS HSE I&C IS KCS
Expansion Alternating Current Ambient American Petroleum Institute Atmospheric Breathing Apparatus Burner Control System Blowdown Valve Break Glass Unit Central Control Room Closed Drain Condensate to Gas Ratio Cause and Effect Carbon dioxide Carbon Steel Car-Seal Open Double Block Decibel Double Block & Bleed Distributed Control System Drive End Differential Pressure Emergency Diesel Generator Emergency Shutdown Fire & Gas Full Vacuum Fire water Fire Zone Gas Chromatograph Gas Gathering Station Gas to Oil Ratio Gas Treatment Plant Hydrogen Sulphide Hydrocarbon High High Human Machine Interface High Pressure High Pressure Separator Health, Safety and Environment Instrument & Control Intrinsically Safe Killed Carbon Steel
Operations Page 10 of 275
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
Acronym KOD LC LCP LCS LCV LEL LL LO LP LPG LSS LTS MMSCFD MP N2 NC NDE NO NPSH O&M O/L ORP P&ID PB PCV PMS POM PPE ppm ppmv ppmw PSD PSV PTW ROV RTU RV RVP SB SBB SGS TCV TDS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Expansion Knock Out Drum Lock Close Local Control Panel Local Control Station Level Control Valve Lower Explosive Limit Low Low Lock Open Low Pressure Liquified Petroleum Gas Low Speed Side; Low Signal Selector Low Temperature Separator Million Standard Cubic Feet Per Day Medium Pressure Nitrogen Normally Closed Non-Drive End Normally Open Net Positive Suction Head Operation & Maintenance Outlet Oxygen Reduction Potential Piping and Instrumentation Diagram Pushbutton Pressure Control Valve Power Management System Plant Operating Manual Personal Protective Equipment Parts Per Million Parts Per Million by Volume Parts Per Million by Weight Process Shutdown Pressure Safety Valve Permit to Work Remote Operated valve Remote Terminal Unit Relief Valve Reid Vapour Pressure Single Block Single Block & Bleed Satellite Gathering station Temperature Control Valve Total Dissolved Solids
Operations Page 11 of 275
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Acronym TEG TSS TVP UC UCP UPS WHCP WHFP WPT 2.0
Operations Page 12 of 275
Expansion Tri-Ethylene Glycol Total Suspended Solids True Vapour Pressure Utility Connection Unit Control Panel Uninterrupted Power Supply Well head Control Panel Well head Flowing Pressure Working Pressure & Temperature
TERMINOLOGY
Acid Gas Antifoam Agent API Gravity
Aromatics
Auto Ignition Point Balanced Draught Barrel Block Valve Catalyst
Ceramic Balls Coalescer Condensate Dehydration
Gas with H2S and CO2 content An additive used for controlling foam in some lubricating oils. It is used in DIPA (Di-Iso Propanol amine), Sulfinol and TEG Unit API degree is used for reporting the gravity of a petroleum product. The degree API is related to the specific gravity scale (15C/15C) by the formula: Degree API = (141.5/Sp. Gr. 15C/15C) – 131.5 A group of hydrocarbons having at least one ring structure of six carbon atoms, each of the latter having one valency outside the ring. Typical aromatics are: benzene, toluene, xylene, phenol (all mono-aromatics) and naphthalene (a di-aromatic) The temperature at which the vapour given off by a sample will burn in air without any ignition source A method of furnace air control using both forced and induced draught fans A standard measure of crude oil quantity; equivalent to 35 imperial gallons, 42 US gallons or 159 litres A valve used for isolation of equipment A substance added to a system of reactants which will accelerate the desired reactions, while emerging virtually unaltered from the process. The catalyst allows the reaction to take place at a temperature at which the uncatalyzed reaction would proceed too slowly for practical purposes. Used extensively in secondary processes Balls of chemically inert ceramic, used as filler and support in reactors etc. A vessel packed with steel wool, glass wool, polypropylene wool or felt used to remove fine droplets of treating liquids or water from a petroleum product Liquid separated from hydrocarbon gas in a Gas-Liquid Seperator which is typically having composition more than C5+. It is normally used as Petrochemical Feed stock. The removal of water from gas produced in association with oil, or
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
ESD Level-1 Shutdown ESD Level-2 Shutdown ESD Level-3 Shutdown Gas Turbine Hydrate
KOD
LEL LPG
Mercaptans
Mole %
Purging
Pyrophoric Schoepentoeter Sour Gas Stabiliser
Operations Page 13 of 275
from gas from gas-condensate wells ESD Level-1 shutdown will open all the depressurising valves at the same time ESD Level-2 shutdown will enable depressurisation, allowing for operator action if required ESD Level-3 shutdowns are used only to isolate or shutdown systems. Individual units/equipment may be depressurised if necessary An engine in which gas (as distinct from steam) is directed, under pressure, against a series of turbine blades. The energy contained in the rapidly expanding gas is converted into rotary motion A compound formed by the chemical union of water with a molecule of some other hydrocarbon. Gas hydrates, formed from water and, for example methane, may cause plugging of the tubing and flow lines of gas wells A vessel, constructed with baffles, through which a mixture of gas and liquid is passed to disengage one from the other. The heavier liquid particulates get separated from lighter gas due to gravitational force. Lower Explosive Limit - Leanest mixture that will explode. A greater air and hydrocarbon ratio will not ignite Liquefied Petroleum Gas is a mixture of Propane & Butane which can be stored under elevated pressure as a liquid at atmospheric temperatures (‘bottled gas’). It is widely used for cooking and domestic heating. Typically contains Propane≤30 Vol%, Butane≤ 70Vol% Mercaptans or alkyl-hydrosulphides are organic compounds of carbon, hydrogen and sulphur. They have a bad odour and frequently occur in unrefined gasoline. Ethyl Mercapton is added as an odorant in commercial LPG. An expression of the percent composition of a mixture in terms of moles. The relative numbers of moles are computed by dividing the numbers of units of weight of the individual constituents by their respective molecular weights The removal of one fluid from a vessel or plant by introduction and subsequent evacuation of a second fluid. A common usage of this operation is in the removal of hydrocarbon vapours or air from a plant by flushing with nitrogen Catches fire spontaneously upon contact with air. Certain forms of iron sulphide exhibit this tendency (Pyrophoric iron) An internal distribution device, sideways or downwards pointing. Gas which contains objectionable amounts of contaminants, e.g. hydrogen sulphide and other corrosive sulphur compounds A fractionating column designed to make a sharp separation between very volatile components and gasoline from Naphtha, casing head gasoline or pressure distillate, thus controlling the gasoline’s Reid vapour pressure
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Stripping
Total Suspended Solids Turn Down
3.0
Page 14 of 275
Removal of the lightest fractions from a mixture. The process is usually carried out by passing the hot liquid from a flash drum or tower into a stripping vessel or stripping section of a column, through which open steam or inert gas is passed to remove the more volatile components of the cut A water specification with undissolved solid matter greater than 1.5 microns Amount or percentage by which a unit or plant may be turned down from its rated capacity. Typically 40% is the minimum. (The plants are designed to run at/or close to maximum)
UNIT OF MEASUREMENT
BOPD BPD BWPD CFD kg/h kW M m3/h mg/l MM MMSCFD Nm3/h ppb ppmv ppmw S STOBPD
4.0
Operations
Barrels of Oil Per Day Barrels Per Day Barrels of Water Per Day Cubic Feet Per Day Kilogram Per Hour Kilowatt Thousand Cubic meter Per Hour Milligram Per Litre Million Million Standard Cubic Feet Per Day Normal Cubic Meter Per Hour Parts Per Billion Parts Per Million by Volume Parts Per Million by Weight Standard Conditions at 15°C and 1 atm Standard Oil Barrels Per Day
OBJECTIVE OF OPERATION MANUAL
The objective of this manual is to guide and provide an overview of the GGS facilities, and a detailed description of Process and Control, Start-up and Shutdown of the plants. These manual details the safety measures, built-in protections employed, handling of emergencies in operation and start-up of the GGS facilities. This manual is to be used in conjunction with other vendor manuals; it summarizes various aspects of engineering including process, mechanical, electrical and control & instrumentation.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 15 of 275
The manual describes process, utilities, offsite, the activities required for the plant start-up and shutdown, and, controls and safety hazards in the plant in various sections as detailed below: o
Section 1: A general introduction of the facilities
o
Section 2: HSE aspects
o
Section 3: Equipment Specification
o
Section 4: Process and Control Description
o
Sections 5 & 6: Electrical, Instrumentation and Emergency shutdown (ESD)
o
Section 7: F&G systems
o
Section 8: Telecom
o
Sections 9, 10 and 11: Product Specification, Pre-Requisites for Start-up and Startup procedures for Utilities.
o
Sections 12, 13 and 14: Plant Start-up, Normal Operating & Monitoring and Plant Start-up after Emergency Shutdown.
o
Section 15 & 16: Troubleshooting Operations and Shutdown procedures.
o
The Annexure Section contains Plot plan, PFD, Heat and Material balance, Alarms & Trip schedule, Cause & Effect diagram, Utility summary and Vendor Operation Manual references.
Though plant safety aspects are addressed in detail, this manual is not intended in any way to supersede safety practices approved by the Company and/or adopted as per manufacturers’ standards that should be followed by all personnel involved with these facilities. Step-by-step instructions and procedures for plant Start-up operations are discussed and should be used as a guideline . However it is cautioned that all scenarios and emergencies arising during plant operation cannot be visualized and explained in an Operating Manual. 5.0
PREAMBLE
Ebla Production Facilities consist of Well heads & Flowlines, Gas Gathering Station (GGS), Trunk line and Gas Treatment Plant (GTP). The production capacity of the plants is rated for 80 MMSCFD of Gas and 22.5 m3/h of Condensate. There are seven Gas Production Wells in Ash-Shaer facilities. The Well Fluid comprises of Gas and Condensate. The well fluids are transported to manifolds through trunk lines and then to a high pressure Production Separator in GGS. The Production Separator is a threephase separator vessel where the gas, condensate and produced water are separated. The field reserve profiles indicate that the well-pressure will be high during the initial phase of production and then the well-pressure will be reduced substantially. Hence the production operation is termed as Initial-Phase (HP-Phase) and Normal Operation (LP-Phase) of the Project. During the HP production phase, the pressure in the well
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 16 of 275
head is adequate for transportation of fluid to GTP, located 76 km away from GGS. However during the LP Phase, a Field Gas Compressor and High Pressure Booster Condensate Pumps are installed in GGS to compensate the pressure loss during transportation to GTP, processing at treatment plants in GTP and then to export the gas to the existing high pressure gas grid in Syria. The gas from Production Separator is dried in Glycol-operated Dehydration Unit (moisture: 1.5 lb/MMSCF); similarly the water content in Condensate (water specification: 200 ppmv) is removed before transporting to GTP. The condensate and dried gas are mixed and then transported to GTP through a Trunk line. At the Gas Treatment Plant (GTP), the gas and condensate are received in a Slug Catcher which knocks off the condensate from the gas. The condensate is sent to a Stabiliser which produces stabilised condensate and is sent to Condensate Storage Tanks. The gas from the slug catcher is sent to Gas Dehydration Unit which contains Molecular Sieves to remove the moisture down to 0.1 ppmv level. The cooled gas from Turbo-expander exchanges its heat with incoming feed gas and is recompressed in Expander-Compressor to 36 barg. The dried gas pressure is boosted in a Sales Gas Compressor and exported through Sales Gas Grid. The liquid separated from the cooled gas (Turbo-Expander) and the Low Temperature Separator flows to De-ethanizer for removal of uncondensed C1 and C2 components; this is then compressed and recycled to the suction of Sales Gas Compressor for export. The De-ethanizer bottoms are sent to De-butanizer to separate Stabilised Condensate and LPG. The LPG is dosed with an odorant (Ethyl Mercapton) in a dosing facility and sent for LPG truck filling. Condensate flows to storage tanks from where it is exported. Both GGS and GTP are provided with utilities such as Plant Air, Instrument Air and Nitrogen Generation Unit. Also Gas Turbo-Generators and Emergency Diesel Generators are provided in GGS as well as GTP. Both units are provided with Utility Water and Potable Water Systems. Fire Water System is provided only in GTP. The plant operations are executed with DCS at both units. The GTP has the provision to operate GGS and Well heads from its Control Room. 6.0
EMERGENCY SHUTDOWN
The Emergency Shutdown (ESD) system forms an integral part of the overall Plant Safety system. A separate ESD system is provided at Wellheads, GGS and GTP. The ESD system at GGS and GTP shall operate on three hierarchical levels, namely ESD-1, 2 & 3. ESD Level 1: This represents the highest level of emergency that may occur at the facility. ESD Level-1 will shutdown and depressurize the Process facilities. ESD Level 2: This is activated in the event of a significant process abnormality at the facilities. Operation of the facility shall be stopped by closing dedicated XVs and tripping all process equipment. ESD Level 3: ESD Level-3 shutdown is non-emergency process abnormalities affecting only one equipment item or unit. ESD Level-3 trips are provided primarily for equipment protection like shutdown of a Compressor on High-High discharge temperature and shutdown of Glycol Dehydration unit on High-High level in the Inlet Separator.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
7.0
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 17 of 275
INTENDED USERS
It is intended that this manual be used by the Operating Personnel to give equipment description, system control and a start-up guideline .Note: the start-up section is intended as a guideline and not to replace the Operating Procedures .
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 18 of 275
SECTION II HEALTH, SAFETY AND ENVIRONMENT
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 19 of 275
COMMITTMENT TO TOTAL LOSS MANAGEMENT It is a fundamental commitment of Petro-Canada Syria to safely manage all risk which could impact its Employees, Contractors, Stakeholders, Environment, and Assets by: providing a safe work environment; developing the competency of a well-trained and knowledgeable workforce; protecting the health, security and well-being of employees; avoiding, minimizing or safely managing the impacts of our operations on the natural environment and on the communities in which we operate; dealing openly with stakeholders who may have an interest in our operations or development projects; supporting research on the health and environmental effects of our products, processes and wastes; avoiding waste and conserving energy and natural resources; setting and reviewing prudent, health, safety and environmental targets; and establishing appropriate programs aimed at compliance with applicable regulatory standards. To support these goals, Petro-Canada incorporates a Total Loss Management (TLM) system in its business and operations. TLM serves as the company's overarching framework for health, safety and environmental performance. This provides clear management expectations; detailing employee responsibilities and serving as a mechanism for ongoing stewardship and continuous improvement through a program of regularly scheduled facility inspections and audits. Petro-Canada will make efforts to inform workers, governments, customers and the public about potential hazards inherent in the nature of our work or in the products we handle and sell. The Company recognizes that each worker has a vital role in protecting themselves, others and the environment from potential hazards. Our managers, employees and others engaged on our behalf are expected to carry out their duties in a manner designed to protect themselves, their fellow workers, the public, the environment and the physical assets of the Company. Guidance is available to customers in the safe handling of our products during transport, storage, use as well as recycling or disposal methods. We are prepared to respond to unplanned events with suitable emergency response plans and management processes should the need arise.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 20 of 275
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 21 of 275
HEALTH, SAFETY and ENVIROMENT at the EBLA Gas Project As you read the technical information in this manual, you must also be aware of some of the hazards and risk involved in the operation of the GGS. To assist in mitigating these risks to an acceptable level, various tools have been developed and are available to provide all workers in ultimately working towards achieving Zero Harm. Although not fully inclusive, the following are some of the risk that may be encountered or associated with the operation of the GGS: Hot & Cold equipment and process temperatures Pressure Trip Hazards Heat Exhaustion Chemical Exposure ( Inhibitors etc.) Nitrogen Hydrocarbons Noise Fall hazards Back& Hand Injuries Spills HEALTH AND SAFETY:
Safety-starts with you! It is the expectation that everyone must follow all Codes of Practice, site specific procedures and work instructions, and wear the proper Personal Protective Equipment at all times when performing their assigned task/job. Although not fully inclusive, the following are some of the tools that will assist you in eliminating or reducing the Risks and Hazards:
Safety hard hats Safety boots Safety glasses Ear Plugs/Muffs as posted Coveralls FRC Gloves Codes of Practice
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 22 of 275
Job Safety Analysis (JSA) Training Procedures and work instructions Site Inspection / audits Event Reporting Pre-job meeting (tool box talks), and MSDS (Material Safety Data Sheets) are provided to identify the potential hazards and the proper method for to handling of all chemicals used or produced on site.
One of our basic and simple principles is to determine which behaviors lead to incidents occurring, and then initiate improvement to our Management Systems to eliminate or reduce the unsafe behaviours and incident potential. The most effective and pro-active method of avoiding accidents is through a worker to worker behaviour based safety process. This is a worker observation process designed to help identify unsafe behaviours, unsafe acts and/or unsafe conditions before they can cause a loss. Task Risk Assessments will be incorporated into the work scope for the operation of the EBLA Gas Treatment Project. The Risk Assessment process is an essential component to ensuring the safe and efficient operation. All mitigation measures that are identified must be implemented to reduce the risk to as low as reasonably practicable. Environmental: Effects to the environment were considered during the design phase for this new facility. Some of the equipment in the plant that has been designed to protect the environment are: flaring systems, closed drain system, open drain system with holding ponds and spill kits. Housekeeping is a key part of maintaining a safe and clean working environment. The Ebla Gas Treatment Project has also developed a waste management strategy for items like filter disposal. ALWAYS REMEMBER – IF IN DOUBT, ASK! For further information or assistance contact your supervisor or HS&E representative.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
SECTION III HAZOPS & ROUNDS
Operations Page 23 of 275
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 24 of 275
The following list are the Hazops action items that must be followed to ensure the safety of personnel and equipment damage Hazop Action No. 372 Confined space entry shall be as per company PTW procedure. It may be required to inspect the vessel internals or repair a vessel/drum or Closed Drain Drum boot. After draining the vessel and purging with N2, it should be dampened by water source to avoid any fire due to pyrophoric iron deposits. Also purge it for sufficient time such that the vessel is free from H2S/hydrocarbon content before vessel entry. There should not be any traces of H2S in the vessel before vessel entry. Proper PPEs should be used for vessel entry against H2S/Hydrocarbon presence. Hazop Action No. 30 Special precautions need to be taken on Vessels like Production Separator prior to releasing them to Maintenance/Turnaround Inspection. Even though H2S content is less than 100 ppm there will be considerable accumulation of pyrophoric scale over a prolonged period of operation. The pyrophoric dust will catch fire when it is exposed to atmosphere. Before opening the Vessel, the Separator shall be dampened from a water source. Disposal of the pyrophoric dust/scale shall be as per Company procedure for disposal of hazardous waste and shall not be dumped in Plant areas which will lead to fire accidents. Pyrophoric fire prevention measures are to be put in place (including availability of relevant portable fire extinguishers) Hazop Action No. 67 Handling and disposal of Contaminated filter Cartridges / Coalescer elements should be done in a safe manner. As these filters contain hazardous sulphur and nitrogen compounds this should be collected and disposed in designated storage areas. Proper PPE’s precautions to all personnel involved in handling the contaminated equipments to waste storage area. Hazop Action No. 31 When releasing Condensate/Produced Water Storage tanks, Condensate pumps/Filters, proper safety precautions are to be taken as per PTW Procedures and for vessel entry by Personnel. Check for Oxygen/Toxic HC components. The vessels are damped from a water source to avoid pyrophoric iron fires. Naturally Occurring Radioactive Material (NORM) and Low Specific Activity (LSA) Scale can appear during the drilling and process phases of Oil and Gas exploration and tend to deposit along with other scale. Low Specific Activity scale (LSA) which are found adhering to pipe and equipment internals produce potential radiation illness mainly due to Radium-226 produced from the decay of naturally occurring Uranium-238. Hence Radioactive Detection and PPE’s for protection against potential radiation illness should be used. The waste removed from Condensate storage/Produced water storage tanks/cartridge filter should be disposed off at locations specifically marked/designated as Waste holdup/storage area. The Waste disposal area shall be clearly fenced, marked and identified with safety tags/boards indicating warnings/dangers due to radioactive substances.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 25 of 275
o Personnel involved in the operation should wear Breathing Apparatus (BA) sets o Flange is broken and hydrocarbon concentration measured o Purging using N2 continues, as necessary o When hydrocarbon concentration drops below 10 ppm, the ‘All Clear’ is given and normal work activities can recommence Hazop Action No. 384 The capacity of the Holding Pond is designed for the worst rainfall conditions. Partially open manual valves in the Water Disposal Pumps will cause overflow of water from the Holding pond to be spilled over to the surrounding environment. Normally the Holding pond receives non-contaminated water from the Open Drain Sump and Storm water. If entrained oil is present in the Holding Pond, it can be recycled to the open drain sump for reprocessing. Under these conditions of entrained oil in the Holding pond, over flow of water from Holding pond will create environmental problems. A portable skimmer can be employed to remove traces of oil in the Holding Pond so that at any time the water is free of oil in the Holding pond. A portable skimmer available at GTP also could be used. If heavy rainfall occurs for a considerable period, a separate Operator can be stationed round the clock to monitor the Levels and quality of water for the Open Drain System. Hazop Action No. 391 The contaminated water from the Open Drain Sump is pumped by Open Drain Contaminated Sump Pump (332-P-002A/S) to Produced Water Storage Tanks through a check valve and 3” dip pipeline with a siphon breaker. If Check valve is passing and water level is below dip leg level, then there will be gas migration from Produced Water tank to Contaminated Open Drain Sump. Hence the Operating personnel should ensure water level above dipleg and then only open the valve to the Contaminated Sump Drain Pump which will prevent gas migration and thereby avoiding potential Fire and Explosion hazard. Hazop Action No. 1200 Analyse Diesel quality prior to unloading from Diesel Truck. The diesel quality shall meet the specification including water content of less than 1000 ppm free water. After the Diesel unloading into the Diesel tank 322-T-001receipt, proper settling time to be given so that water settles and water is drained out from the bottom drain of the tank. Again check diesel quality by taking a sample at the outlet of Diesel Filter Coalescer. The water content shall be less than 100 ppm. This sampling should be done during normal operation to ascertain the quality of diesel and proper functioning of Diesel Filter Coalescer. Hence proper monitoring of Diesel quality shall be ensured. Otherwise water in diesel more than specification will cause loss of ignition in EDG.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 26 of 275
Hazop Action No. 1203 The Diesel tank (322-T-001) is also provided with heating coils which can be used during winter when the temperature may reach below sub zero. Maintain proper temperature of diesel in the Diesel tank so that high water content does not lead to ice formation and thereby choking filter/pipeline. Ensure to drain water from Coalescer periodically to maintain diesel quality. Hazop Action No. 1195 Transfer diesel from Diesel Tank (322-T-001) to EDG by monitoring tank level when the level in the Day tank is low. Transfer diesel from Tank with 322-P-001A/S pump to day tank and closely watch the Day tank level. Malfunction of the Day tank float valve will lead to diesel overflow/spill and possible fire hazards. Hence an operator has to manually check and ensure proper coordination while filling day tank of EDG. Hazop Action No: 550 Monitor the dewpoint analyzer (325-AI-4520 for Train-A and 325-AI-4570 for Train-B) for Train-A continuously and ensure the dewpoint is maintained at -350C at 7.5 barg. If the dewpoint increases to -340C at 7.5 barg, immediately high alarm 325-AIH-4520 is activated. Always keep the standby Air Drier regenerated and kept ready so that it can be lined-up immediately if there is high dewpoint alarm. Excessive content of moisture in Instrument air may create accelerated corrosion in downstream users. Hazop Action No-300 The Methanol transfer to Tank 329-T-001 as well as tote tank is carried out using 329-P001A/S. Ensure there is always continous supply of LP fuel gas for the blanketing of Methanol Storage Tank 329-T-001. During methanol transfer ( Either to storage Tank 329-T-001 or to tote tank) if there is outage of LP fuel gas, stop the methanol transfer immediately. The transfer/unloading of methanol during LP fuel gas outage will lead to oxygen ingress into the tank and mix with oxygen to form a potentially explosive mixture. Hazop Action No. 26 In case of extended shutdown period during winter conditions, the water in the Produced water lines from Production Seperator should be completely drained. During Start-up, line-up heat tracing for all instruments and process lines before start-up. Ensure to switch “ON” heat-tracing lines for Produced water lines so as to avoid ice formation in water lines and reduce corrosion. While Start-up after Prolonged/Annual shutdown in winter, ensure to fully drain the Produced water lines so that freezing of the water lines are avoided. It is also recommended to drain out Produced water lines when the plant is taken on line after Annual shutdown. Failure of the heat tracing will lead to ice formation in the produced water lines and this will result to water carryover in condensate and causes accelerated corrosion in the pipeline.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 27 of 275
Hazop Action No. 758 Drain the liquid accumulated in the Vent Gas KO Drum (305-V-003) by observing the Level gauge 305-LG-3135. If it is prolonged shutdown drain KOD and also ensure to switch on the heat tracing on the pipelines to maintain the fluidity in the line. The Field operators should ensure regular observance of the Vent Gas KOD liquid level and drain the liquid at frequent intervals. If the level builds up, then entrainment to Blowers will cause potential damage to the Blowers. Drain the Blowers casing of the selected Vent Gas blowers 305-K-002A/B or C/D by opening eight ball valves on each Blower casing assuring that all possible condensate is drained off before burner ignition and then close the drain valves. Hazop Action No. 757 In cold weather conditions TEG (Tri-Ethylene Glycol) is viscous and has to be warmed up to facilitate pouring.
During winter months, when air temperature might fall to -15°C (min. ambient temperature) ascertain that Gas Dehydration Column bottom, the wet condensate outlet line and the chimney tray portion of the column are heated by electrical tracing. Switch on the electric tracing system on the level instruments installed on the Flash Drum 305-V-002, on the TEG Reboiler 305-H-001, TEG Surge Drum 305-V-005, stand-by pump and in general where electrical tracing is given. Increased viscosity of glycol in Surge vessel may affect the pumping and potentially damage the glycol circulation pumps at cold operating conditions. As the glycol lines are heat traced and insulated to retain the hot condition, it becomes necessary to restart the electrical heat tracing and then start the Glycol Pumps especially after prolonged shutdown and cold winter conditions.
Hazop Action No. 767 Check for potential leaks in the glycol circuit and arrest leaks on TEG lines wherever possible. Look for potential leaks like foaming in Contactor, escape of TEG vapours from TEG Reflux Condenser and Glycol pump gland leaks and top up when required. If the Glycol surge drum level reaches the LLLL value (305-LALL-3116) of 300mm, it will cause tripping of Glycol Pumps. Loss of Glycol circulation will lead to off-spec dehydrated gas as indicated 305-AIH-3022. Due to this water carryover it will cause accelerated corrosion of the trunk line. In case of losing glycol circulation and initiation of off spec gas alarm 305-AIH-3022 the operator has to initiate ESD-3 trip of Gas Dehydration Package. Hazop Action No. 766 Operator should inspect the Vent Gas KOD (305-V-003) level by monitoring liquid level of KOD at regular intervals by observing level gauge 305-LG-3135. Check the Liquid trap installed on the drain line of the Vent Gas KOD for its operability. Ensure to drain the liquid periodically with care to avoid gas blow-off. If the liquid level is higher it should
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 28 of 275
be drained to avoid carryover to Vent Gas Blowers (305-K-002A/B/C/D) and causing potential damage to the Vent Gas Blowers. Hazop Action No. 42 During the Start-up phase, the Gas Dehydration pressure is controlled by operating 305PV-3024. After stabilization of unit, the Dehydration column pressure control is switched over to Split Range controller 305-PIC-3009. In case of inadvertent action to open 305PV-3024 fully, will result in depressurisation of the Dehydration Column. This lower pressure will lead to lower efficiency of the Dehydration column. The following trouble shooting points alerts the Operator in case of inadvertent opening of 305-PIC-3024: The operator will be alerted at 80.6 barg by Low pressure alarm 305-PAL-3009 and should take immediate action to identify the cause and close 305-PV-3024 High flow alarm in the Flare Header by 331-FAH-5126. The bigger control valve 305-PV-3009A closes fully and the pressure is controlled only by smaller control valve 305-PV-3009B However if the Operator does not respond to the above mentioned alarms at 80.6 barg, then at 76.3 barg, the actuation by 305-PALL-3012 will cause ESD-3 shutdown which will cause unnecessary flaring at the upstream section of GGS. Hazop Action No. 47 The ESD-3 shutdown of Gas Dehydration/TEG Regeneration unit closes 305-XV-3001, the TEG Column 305-C-001 Bottom liquid outlet ESD valve. After the ESD shutdown the steps of glycol circulation, Heat-up of Glycol and the pressurisation of feed gas and the other requirements are to be followed as given below in Section 12.6.2. If the glycol circulation, Gas pressurisation and other set of requirements are not followed, it will lead to foaming which will cause glycol carry over to the trunkline. Hazop Action No. 43 If ESD-3 trip is actuated by initiation of 305-PALL-309 (due to inadvertent action of fully opening 305-PV-3024), the Condensate injection to the trunkline should be stopped if it is a prolonged ESD-3 shutdown. Immediately after the ESD-3 trip, the Production Separator can be operated near turndown capacity to avoid excessive flaring and condensate can still be routed to the Trunk line. For prolonged durations of ESD-3 shutdown, the condensate injection to trunkline should be stopped. . Injection of Condensate into the trunkline without dehydrated gas will accelerate corrosion in Trunkline and cause slug receipts at the GTP. Ensure TEG Incinerator is running with fuel gas and maintain the TEG circulation. Reset and start firing the TEG Regeneration Reboiler and stabilise the Gas Dehydration system before lining up condensate and dehydrated gas to the Trunkline. Hazop Action No. 27 If the Plant is taken for Annual/Long shutdowns, it is required to drain all the Produced water lines to prevent ice formation and corrosion of pipeline.. In case of failure to switch on heat tracing, will lead to blocking of Produced water lines and thereby increases water level in Production Separator. This will lead to water carryover in condensate and
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 29 of 275
corrosion in the Trunkline. Hence a regular schedule should be prepared to do regular monitoring and preventive maintenance of the Heat Tracing. Hazop Action No. 67 Handling and disposal of Contaminated filter Cartridges/Coalescer elements should be done in safe manner. As these filters contain hazardous sulphur and nitrogen compounds this should be collected and disposed in designated storage areas. Proper PPEs as given in Section 2.3 and Precautions should be given to all personnel involved in handling the contaminated equipments to waste storage area. Hazop Action No. 522: Any leak in the Dry gas/Lean TEG Exchanger will lead to glycol carryover along with dehydrated gas. This will result drop in Surge drum level and initiates an Low level alarm (305-LAL-3115) due to loss of glycol. As there is no isolation bypass available for the shell & tube sides, unit has to be shutdown if leak develops on either side. As there is a potential leakage due to corrosion of the 305-E-004 tube bundles, proper monitoring has to be done which will reduce the 305-E-004 tube bundle leakages.
Proper monitoring of corrosion coupon 305-CC-3080 on the Gas Dehydration Column overhead vapour line. If corrosion rate is more increase the corrosion inhibitor injection rate at the outlet of TEG carbon filter. A spare tube bundle availability helps in quick start-up of the Gas Dehydration plant in case of any leak Provide isolation and bypass valves for both shell and tube side. Note: During winter period (when the ambient temperature falls below –15C), drain the column bottom and condensate outlet pipeline to column bottom, in order to avoid liquid freezing. In case of longer shutdown during winter, glycol also need to be drained for non- traced lines in order to avoid freezing due to the lower ambient temperatures (–15°C) and TEG freezing temperature of –7°C. Hazop Action No. 360 The Closed system will be positively isolated from the process by closing of valves at equipment during normal operation. The draining to Closed Drain drum is done one equipment at a time to have a better control and draining so as to avoid overflow of Closed Drain Drum. At any time, two equipments will not be drained simultaneously. Draining of more than one equipment may lead to liquid build-up in Closed drain drum and liquid carryover to the Flare header which is undesirable. Hence proper coordination should be planned in advance regarding the draining of liquids from equipments during shutdown. Where equipment is connected to a Closed Drain System for draining prior to Maintenance or inspection positive isolation for e.g. a spectacle blind will be provided between the equipment and the drain. The drain will be positively isolated during normal operation and the draining will be performed after shutdown and depressurization of the equipment item. The only exception is draining of Oil pad from Produced Water storage
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 30 of 275
Tank (334-T-001) and contaminated water storage tank (834-T-001) at GTP. Pressurized draining will be allowed during start-up like draining of Compressor casing drains. For drains which need to be used under normal operation like level instruments/bridle drains, the spectacle blind is left in open position and operators will turn it closed as and when required for equipment isolation. Consequently intermittent drainage required during normal operation will be returned to the process. Hazop Action No. 961 When the Gas Dehydration Plant is shutdown for longer periods during winter, then TEG needs to be cooled sufficiently and drained to TEG Drain vessel.
Hazop Item # #766
Draining Hot TEG above 60C will damage drain piping and also hazardous for handling. Hence circulate TEG by the Glycol circulation pumps through Glycol Cooler. Bring down the temperature below 60C and transfer to storage. Drain liquid from vessels to TEG Drain drum and pump to storage. Rounds Equipment
Location
Vent Gas KO Drum 305-V-003 Nitrogen Storage Receiver 324-V-001 Wet Air Receiver 325V-001 Instrument Air Receiver 325-V-002 Heat tracing
TEG Regeneration
Time Sequence 2x per shift
Action
Nitrogen Unit
2x per shift
Instrument Air System
2x per shift
Instrument Air System
2x per shift
Monitor the level and liquid trap base operation Monitor the level
GGS Unit
1x per shift
Monitor the local panel
Monitor the level and liquid trap base operation Monitor the level
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 31 of 275
SECTION V GAS GATHERING STATION
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
1.0
INTRODUCTION
Operations Page 32 of 275
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
1.1
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 33 of 275
OVERVIEW OF GAS GATHERING STATION
The multiphase fluid from each of the seven Production Well heads in the Ash-Shaer area is transported to a Production Manifold. From the Production Manifold, the multiphase fluid is transported to Production Separator in the Gas Gathering Station (GGS). The Production Separator is a three-phase Separator Vessel where the gas, condensate and water are separated. In the Early Production Phase i.e., at the beginning of the Reservoir production, the well head pressure is high enough to transport the gases from the well head to the Gas Treatment Plant (GTP) through the GGS and Trunk lines. At the later stage of gas production when the Well head pressure comes down, the Field Gas Compressor is used to boost the pressure. In the early production phase, the differential pressure required is low and hence Early-operation Condensate Pumps will be in operation. Later, when the Well head pressure drops, the Field Gas Compressor is operated and Early-operation Condensate Pumps will be taken out of service and Condensate Pumps will take over. The gas from the Production Separator is routed to Gas Dehydration Column where water is removed by using lean Tri-Ethylene Glycol (TEG). The rich TEG generated in the Gas Dehydration Column is regenerated in TEG Regeneration System and returned to the Gas Dehydration Column as lean TEG. The condensate and water are separated in the Production Separator by a weir arrangement. The condensate is pumped by Condensate Pumps to a Condensate Solid Filter and Condensate Coalescer where the fine particles and fine water droplets are removed from the condensate. Finally, the dehydrated gas and condensate are mixed together and transported through a 76 km trunk line to the Gas Treatment Plant (GTP). GTP can be monitored from GGS control room, but no control of GTP is possible from GGS, whereas GGS data can be monitored and controlled from GTP control room.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
2.0
SPECIFIC SAFETY HAZARDS
Operations Page 34 of 275
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
2.1
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 35 of 275
GENERAL SAFETY PRECAUTIONS AND OPERATIONS
The safety systems in Ebla Project facilities are designed to protect personnel, environment and assets from the threats of production hazards. A minimum risk level is achieved by adopting the following safety aspects: o
Avoiding exposure to potential hazards during operations
o
Minimising the potential (frequency) for hazardous occurrences (release of hydrocarbons, hydrocarbon flammable gases and any other abnormal hazardous events)
o
Containing and minimising the consequence of the hazards (fire, explosion and toxic gas releases)
o
Providing the means of escape and evacuation from such hazards
o
Proving a safe working environment for Plant personnel
As the condensate and gas are sweet, there is no hydrogen sulphide (H2S) hazard involved, however all systems are designed for a H2S concentration of 100 ppm. ENTRY INTO CONFINED SPACE Hazop Action No. 372 Confined space entry shall be as per company PTW procedure. It may be required to inspect the vessel internals or repair a vessel/drum or Closed Drain Drum boot. After draining the vessel and purging with N2, it should be dampened by water source to avoid any fire due to pyrophoric iron deposits. Also purge it for sufficient time such that the vessel is free from H2S/hydrocarbon content before vessel entry. There should not be any traces of H2S in the vessel before vessel entry. Proper PPEs should be used for vessel entry against H2S/Hydrocarbon presence. Refer section 2.3 for details HAZARDS OF H2S
H2S can be absorbed into the body by inhalation.
H2S is irritating to the eyes and the respiratory tract; it causes unconsciousness or even death at higher concentrations. At 100 ppm, it causes coughing and loss of sense of smell; at 500 - 700 ppm exposures, it will lead to unconsciousness and death in 30 to 60 minutes. At 1000 ppm, it causes rapid unconsciousness; breathing is stopped, resulting in death.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 36 of 275
It is colourless with a characteristic smell of rotten eggs. It is heavier than air, hence may accumulate in low areas and travel a considerable distance to a source of ignition.
Occupational Exposure Limits: It has a Threshold Limit Value (TLV) of 10 ppm.
When breaking into a process system that contains gas and condensate, it is necessary to take special precautions as follows: o
Area around the specific area is taped off to prevent personnel approaching the worksite
o Personnel carrying out this operation shall take Work Permit, be aware of the hazards associated with nitrogen (N2), Carbon di-oxide (CO2) and H2S and wear appropriate Personal Protective Equipment (PPE)
o As far as possible, the system to be entered is purged using N 2/water dampening prior to opening. This also negates the threat of elemental sulphur and associated corrosion and cracking. o
Hazop Action No. 30 Special precautions need to be taken on Vessels like Production Separator prior to releasing them to Maintenance/Turnaround Inspection. Even though H 2S content is less than 100 ppm there will be considerable accumulation of pyrophoric scale over a prolonged period of operation. The pyrophoric dust will catch fire when it is exposed to atmosphere. Before opening the Vessel, the Separator shall be dampened from a water source. Disposal of the pyrophoric dust/scale shall be as per Company procedure for disposal of hazardous waste and shall not be dumped in Plant areas which will lead to fire accidents. Pyrophoric fire prevention measures are to be put in place (including availability of relevant portable fire extinguishers)
o
Hazop Action No. 67 Handling and disposal of Contaminated filter Cartridges / Coalescer elements should be done in a safe manner. As these filters contain hazardous sulphur and nitrogen compounds this should be collected and disposed in designated storage areas. Proper PPEs as given in Section 2.3 and precautions to all personnel involved in handling the contaminated equipments to waste storage area.
HAZARDS OF RADIOACTIVE MATERIAL
Hazop Action No. 31
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
When
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1 releasing
Condensate/Produced
Water
Operations Page 37 of 275 Storage
tanks,
Condensate
pumps/Filters, proper safety precautions are to be taken as per PTW Procedures and for vessel entry by Personnel. Check for Oxygen/Toxic HC components. The vessels are damped from a water source to avoid pyrophoric iron fires. Naturally Occurring Radioactive Material (NORM) and Low Specific Activity (LSA) Scale can appear during the drilling and process phases of Oil and Gas exploration and tend to deposit along with other scale. Low Specific Activity scale (LSA) which are found adhering to pipe and equipment internals produce potential radiation illness mainly due to Radium-226 produced from the decay of naturally occurring Uranium-238. Hence Radioactive Detection and PPEs for protection against potential radiation illness should be used. The waste removed from Condensate storage/Produced water storage tanks/cartridge filter should be disposed off at locations specifically marked/designated as Waste holdup/storage area. The Waste disposal area shall be clearly fenced, marked and identified with safety tags/boards indicating warnings/dangers due to radioactive substances.
Personnel involved in the operation should wear Breathing Apparatus (BA) sets
Flange is broken and hydrocarbon concentration measured
Purging using N2 continues, as necessary
When hydrocarbon concentration drops below 10 ppm, the ‘All Clear’ is given and normal work activities can recommence
2.2
HAZARDS IN HANDLING CHEMICALS
The GGS involves methanol injection and corrosion inhibitor facilities. The Gas Dehydration handles TEG as absorbent chemical for removing the moisture and uses antifoam compounds for avoiding foaming in the Gas Dehydration Column. 2.2.1 Physical and Chemical Properties of TEG TEG is a clear colourless liquid and highly miscible in water with a boiling point of 285C (545F). In case of leak, isolate the area. Keep away unnecessary and unprotected personnel from entering inside the area. Recover liquid wherever possible and collect liquid in an appropriate container or absorb with an inert material (e.g. vermiculite, dry sand and earth) and place in a chemical waste container. Do not use combustible materials, such as saw dust. Do not flush to sewer. Emergency and First Aid Skin Contact
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 38 of 275
In case of contact, immediately flush the skin with plenty of water for at least 15 minutes. Remove contaminated clothing and shoes. Wash clothing before reuse. Eye Contact If splash occurs, immediately flush the eyes with water for at least 15 minutes, lifting upper and lower eyelids occasionally. 2.2.2 Physical and Chemical Properties of Methanol Methanol is a clear colourless liquid with a characteristic pungent odour; it is miscible in water with a boiling point of 65C (149F). TLV (Threshold limit value)
: 200 ppm
STEL (Short term Exposure limit)
: 250 ppm
In case of leak, isolate the area. Keep unnecessary and unprotected personnel from entering. Contain and recover liquid when possible. Collect liquid in an appropriate container or absorb with an inert material (e.g. vermiculite, dry sand and earth) and place in a chemical waste container. Do not use combustible materials, such as saw dust. Do not flush to sewer. Effects of Over-Exposure
Inhalation and ingestion are harmful and may be fatal
Inhalation may cause headache, nausea, vomiting, dizziness, lower blood pressure and depression of central nervous depression
Acute ingestion may cause blindness, vomiting, headaches, dizziness and gastro-intestinal irritation
Chronic effects include kidney and liver damage
Emergency and First Aid Skin Contact In case of contact, immediately flush the skin with plenty of water for at least 15 minutes. Remove contaminated clothing and shoes. Wash clothing before reuse. Eye Contact If splash occurs, immediately flush the eyes with water for at least 15 minutes, lifting upper and lower eyelids occasionally. 2.2.3 Physical and Chemical Properties of Sodium Hypochlorite Sodium Hypochlorite is a colourless to yellow green liquid with a chlorine like odour; it is miscible in water and decomposes above 1100C (230F). TLV (Threshold limit value)
: 1 ppm
Do not allow spilled material to enter sewers or streams. Flush with water to dilute as much as possible and pump into polyethylene containers for disposal. Avoid heat and contamination with acid materials. Do not use combustible materials such as saw dust
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 39 of 275
to absorb hypochlorite. Aquatic toxicity not established, but bleach, if not diluted may seriously affect aquatic life. Emergency and First Aid Eye Contact If splash occurs on eyes, flush with plenty of water for atleast 15 minutes. Get prompt medical attention immediately. Skin Contact In case of contact, immediately flush the skin with plenty of soap and water. If swallowed drink large quantity of milk or gelatine solution. If these are not available drink large quantity of water. Do not give vinegar or other acids. Do not induce vomiting. Get prompt medical attention. 2.3
PPE REQUIREMENTS
Skin Protection Wear protective impervious gloves such as rubber, neoprene or vinyl with rubber safety shoes and body-covering clean clothing. Eye Protection Use chemical safety goggles plus full face shield to protect against splashing (For Sodium Hypochlorite). Maintain eye-wash fountain and quick-drench facilities in work area. Fire Extinguishing Media Keep on hand water spray, dry chemical, alcohol foam, or carbon dioxide extinguishers. Water or foam may cause frothing. Special Information In the event of fire, wear full protective clothing and Self-Contained Breathing Apparatus (SCBA) with full face-piece, operated in pressure-demand mode or other positive pressure mode.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
3.0
EQUIPMENT SPECIFICATION
Operations Page 40 of 275
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 41 of 275
3.1 METHANOL STORAGE TANK Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Operating Capacity Density at WPT Dimension Material of Construction 3.2
Minimum 82.0 –2.5 45.0
20.0 55.0 800 4100 ID x 5000H Shell/Bottom: Carbon Steel Internals: SS 316L
Unit ºC mbarg ºC mbarg m3 kg/m3 mm
METHANOL LOADING/UNLOADING PUMP
Equipment Tag No. Type Fluid Description Temperature (Min/Max) Suction Pressure (Min/Max) Discharge Pressure Flow Density of Liquid at WPT Viscosity of Liquid at WPT Power Material of Construction
3.3
329-T-001 Tank Methanol Maximum –15.0 180.0 –15.0
329-P-001A/S Centrifugal Methanol Rated –15.0/45.0 –0.012/0.59 1.20 20.0 800 0.7 3.7 Casing: CS; Impeller: CS
Unit ºC bara bara m³/h kg/m³ Cp kW
OPEN DRAIN NON-CONTAMINATED SUMP PUMP
Equipment Tag No. Type Fluid Description Temperature Suction Pressure Discharge Pressure Flow Density of Liquid at WPT Viscosity of Liquid at WPT Power Absorbed at Shaft Material of Construction
332-P-001 A/S Centrifugal Water Rated Min 4.0/Max 45.0 0.152 3.7 50 997 0.9 9.6 Casing: SS 316 L;
Unit ºC barg barg m³/h kg/m³ Cp kW
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Equipment Tag No. 3.4
Material of Construction
332-P-001 A/S Impeller: SS 316 L
332-P-002 A/S Vertical Centrifugal Pump Water with oil Rated Min 4.0/Max 45.0 0.152 2.3 5.0 1000 0.9 3.7 Casing: SS 316 L; Impeller: SS 316 L
Unit ºC barg barg m³/h kg/m³ Cp kW
CLOSED DRAIN DRUM
Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Liquid-Rated flow Density at WPT Material of Construction Dimensions 3.6
Page 42 of 275
OPEN DRAIN CONTAMINATED SUMP PUMP
Equipment Tag No. Type Fluid Description Temperature Suction Pressure Discharge Pressure Flow Density of Liquid at WPT Viscosity of Liquid at WPT Power Absorbed at Shaft
3.5
Operations
333-V-001 Drum -Horizontal Hydrocarbon Gas & Condensate Maximum Minimum –15.0 82.0 5.0 FV 4.0 45.0 0.1 5.0 Condensate - 600/Water - 1000 Shell: CS; Boot Cladding: SS316L 2500 ID X 9000 TT
Unit ºC barg ºC barg kg/h Kg/m3
mm
CLOSED DRAIN DRUM HEATER
Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Density at WPT Material of Construction
333-H-001 Electrical Condensate Maximum –15.0 3.5 –4.0
Minimum 82.0 — 4.0 0.1 600 SS 316L
Unit ºC barg ºC barg kg/m3
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
3.7
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Page 43 of 275
CLOSED DRAIN DRUM PUMP
Equipment Tag No. Type Fluid Description Temperature Suction Pressure Discharge Pressure Flow Density of Liquid at WPT Viscosity of Liquid at WPT Motor Power Material of Construction
3.8
Operations
333-P-001A/B Vertical Centrifugal Hydrocarbon Drains Rated 45 3.66 1.94 5 700 0.47 4.12 Casing: SS316L; Impeller: SS316L
Unit ºC bara bara m³/h kg/m³ Cp kW
LP PRODUCED WATER DISPOSAL PUMP
Equipment Tag No. Type Fluid Description Temperature Suction Pressure Discharge Pressure Flow Density of Liquid at WPT Viscosity of Liquid at WPT Motor Power Material of Construction
334-P-001 A/S Centrifugal Produced Water Rated 45 1.27 5.2 25.5 1200 1.1 11.96 Casing: CS; Impeller: 12% Cr CS
Unit ºC bara bara m³/h kg/m³ Cp kW
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 44 of 275
4.0 PROCESS AND CONTROL DESCRIPTION
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
4.1
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 45 of 275
PRODUCTION SEPARATOR
The Production Separator is a horizontal three-phase separator vessel where the gas, condensate and water are separated. Equipment Specification Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Liquid Quantity (Condensate/Water) Density at Working Pressure & Temp. (WPT) (Condensate/Water) Vapour Quantity Molecular Weight Density at WPT Material of Construction Dimensions
ID Length (T/T)
302-V-001 Three Phase Separator Vessel– Horizontal Hydrocarbon Condensate, Gas & Water Maximum Minimum Unit 82.0 –15.0 ºC 95.2 — barg (kPa) 41.0 7.7 ºC 86.64 25.39 barg (kPa) 14503/38386
kg/h
554.03/956.48
kg/m3
97980 19.28 20.66 Shell: Killed Carbon Steel (KCS) Internals: Duplex Stainless Steel Cladding: Incoloy 825 2700 12800
kg/h kg/kg mole kg/m3
mm mm
4.1.1 Principle of Separation of Water from Oil in Separators The function of a separator is to remove free gas from condensate and water at a specific pressure and temperature. The Production Separator in the GGS is designed to meet the following requirements: o
Liquid must be separated from gas in a primary separating section
o
Gas velocity must be lowered to allow liquids to drop out
o
Gas must be scrubbed through an efficient demister
o
Water and oil must be diverted to a turbulence-free section of the vessel
o
Liquids must be retained in the vessel long enough to allow separation
o
The water–oil interface must be maintained
o
Water and oil must be removed from the vessel at their respective outlets
The basic principle of separation of water from condensate in the separators is by settling of the heavier phase (water) under gravitational force. In a mixture of immiscible liquids, the heavier phase travels downwards and the lighter phase travels upwards. Density of water droplets is higher than the density of condensate
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 46 of 275
(continuous phase). Due to this difference in densities, water droplets will travel downwards under gravitational forces. The higher the size of water droplets, the faster will be the speed of downward movement. Similarly condensate droplets in water phase will travel upwards due to buoyancy forces. This separation of oil and water (free water) phases by gravitational forces due to density difference is called as Gravity Settling. Bulk of the water in the condensate is easily separated as it enters the separators. A typical schematic sketch of Three Phase Separator is illustrated in Fig. 1 as given below. Schematic of Three-Phase Separator
The condensate and the water phase are separated in a Weir Plate and the separated condensate flows over the Weir Plate and collects in the Condensate Compartment. A 600 mm internal Baffle Plate is provided at 3000 mm from the inlet nozzle end of the vessel and at a height of 1000 mm from the bottom of the Separator. This Baffle Plate is required to alleviate separation when slug arrives. The separated gas exits through the top outlet nozzle provided with a Mist Eliminator arrangement capable of separating liquid particles larger than 10 micron size. The Production Separator is maintained at a pressure of 87 barg during the HP phase and 36 barg during the LP phase. ESD valve 302-XV-1104 at Production Separator will depressurize to the Flare Header when ESD Level-1 shutdown is activated. The Safety Valves 302-PSV-100A/302-PSV-100B, is set at 95.2 barg and will open to the Flare Header. The Condensate level is controlled by Level Controller and 302-LIC-1119 controls the Interface level.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 47 of 275
4.1.2 Production Separator Controls 4.1.2.1
Production Separator Pressure Control (HP Mode)
The Production Separator (302-V-001) pressure is linked to the operating pressure of the Gas Dehydration Column Pressure Controller 305-PIC-3009. This maintains backpressure at the Production Separator. However the excess pressure at Production Separator is controlled by Pressure Controller 302-PIC-1137 which relieves the excess pressure to Flare Header. To avoid flaring due to excessive pressure, Choke Valve can be throttled to reduce pressure at Production Separator. Schematic Sketch of production separator and Condensate system is enclosed in Fig. 2 as given below:
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 48 of 275
Fig. 2 – Production Separator and Condensate System Controls
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
4.1.2.2
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 49 of 275
Condensate Level Control
The condensate level is measured by a Level Indicating Controller 302-LIC-1119 which is a master controller cascaded with the Condensate Flow Controller 302-FIC-1182. Early Operation (HP) Mode During the HP mode, the Condensate Level Controller 302-LIC-1119A which takes the same measurement as 302-LIC-1119 controls the Production Separator level by operating the Recirculation Valve (302-LV-1119) of Early Operation Condensate Pumps (302-P-002A/B). 302-LV-1119 will open in case the condensate level is decreasing below the set point. 302-LIC-1119A shall be forced to Manual mode and output driven to 0% under the following conditions:
Plant in Normal Operation (LP mode)
Both Condensate Pumps 302-P-002A/B are stopped
Normal Operation (LP) Mode During the LP mode, the Condensate Pumps are protected against low flow by the minimum flow control valve 302-FV-1130. The condensate recycle flow control valve 302-FV-1130 is controlled by 302-FIC-1130 on the Condensate Pumps (302-P-001A/B) discharge line. 302-FV-1130 tends to open in case of condensate flow is decreasing below the set point which is set at Minimum flow of the Pump. 302-FIC-1130 shall be forced to Manual mode and output driven to 0% under the following conditions:
Plant in Early Operation (HP mode)
Both Condensate Pumps 302-P-001A/B are stopped
Dry Condensate to Export – Flow Control 302-FIC-1182 controls the dry condensate to export flow by throttling the control valve 302-FV-1182 on the dry condensate Export Trunk line. 302-FV-1182 tends to open in case of dry condensate flow increasing above the set point. Override: Dry condensate flow control will be overridden by ‘Low’ condensate pump discharge pressure 302-PIC-1132. This shall be achieved by using a ‘Low signal selector’ block, which will select the lower of 302-FIC-1182 and 302-PIC-1132. The selected controller output will act on 302-FV-1182. The condensate level is monitored by Level Alarms (High High and Low Low) by 302-LAHH-1117 and 302-LALL-1117 respectively. For details, refer Cause & Effect Diagram 250-EPR-CNE-05001. 4.1.2.3
Condensate-Water Interphase Level Control
The condensate-water interface level is controlled by Interface Level Controller 302-LIC-1114 which actuates Produced Water flow to Produced Water Degassing Drum (334-V-001) by level control valve 302-LV-1114. The interface level is monitored by
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 50 of 275
Level Alarms (High-High and Low-Low) 302-LAHH-1116 and 302-LALL-1116 respectively. For details, refer Cause & Effect Diagram 250-EPR-CNE-05001. 4.2
FIELD GAS COMPRESSOR
During the initial HP phase, the Well head gas pressure is adequate to meet the GTP operating pressure. However, during later phase of operation (LP mode) of wells, the Well head pressure will be low and hence it requires a Field Gas Compressor to boost the pressure. During the HP phase, the entire Compressor circuit is kept in bypass condition. The gas flow joins the inlet of the Gas Dehydration Column (305-C-001). FIELD GAS COMPRESSOR SUCTION KNOCK-OUT DRUM Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Liquid Quantity Density at WPT Vapour Quantity Molecular Weight Density at WPT Material of Construction Dimensions
ID Length (T/T)
304-V-001A/B Vessel– Vertical Hydrocarbon Gas Maximum Minimum 110.0 –15.0 95.2 — 41 7.4 86.04 24.8 24.1 717.04 107623 19.28 20.3 Shell: KCS, Clad with SS 316L; Internals: SS 316L 2700 4400
Unit ºC barg (kPa) ºC barg (kPa) kg/s kg/m3 kg/h kg/m3
mm mm
FIELD GAS COMPRESSOR Equipment Tag No. Type Fluid Description Suction Temperature Suction pressure Discharge Temperature Discharge Pressure Flow Molecular Weight Power Material of Construction
304-K-001A/B Centrifugal Wet Hydrocarbon Gas Rated 35.5 24.9 166.3 87.5 97839 19.28 9080 Casing: Duplex Stainless Steel Impeller: Duplex Stainless Steel
Unit ºC bara ºC bara kg/h kW
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 51 of 275
FIELD GAS COMPRESSOR AFTERCOOLER Equipment Tag No. Type Fluid Description Design Temperature – Tube Working Temperature – Tube Design Pressure – Tube Working Pressure – Tube Fluid – Tube Heat Duty Air Design Temperature No. of Fans Material of Construction Coolant
304-E-001A/B Air Cooler & Forced Draft Tube: Wet Hydrocarbon Vapour Maximum Rated — 192 Inlet: 166.2 Outlet: 50.1 — 95.2 Inlet: 87.5 Outlet: 86.8 97839 8254.7 + 10% margin 45 Max.; –15 Min. 4 Tube: SS 316 L + Aluminium fins Air
Unit ºC ºC bara bara kg/h kW ºC No.
4.2.1 Process Description During the LP phase, the gases from the top outlet of the Production Separator (302-V-001) reach the Field Gas Compressor Suction KO Drum (304-V-001A). There are two streams of Compressor Systems; one on duty and the other on standby in parallel mode. The split streams for the two compressor systems are identical, with a Suction Knock-Out Drum, Compressor and Compressor After cooler arrangement. The gas stream enters the Compressor Suction KO Drum-A (304-V-001A) through an ESD Valve 304-XV-1200 provided with an ESD Bypass Valve 304-XV-1201. ESD Valve 304-XV-1200 will open only if the differential pressure (304-PDI-1206) is below 2.5 barg. The Compressor Suction KO Drum consists of Vane-type Inlet Distributor through which the gas enters. The entrained condensate is separated and further fine droplets of condensate (more than 3 micron) are removed in the Demister Pad located at the gas outlet on the KO Drum top. The demister can remove 99% of the particles larger than 3 micron size. The Compressor KOD 304-V-001A is provided with two PSVs 304-PSV-110A and 304-PSV-110B which is set at a pressure of 95.2 barg. The condensate level in the Compressor Suction KOD is controlled by 304-LIC-1210. The Controller acts on Control Valve 304-LV-1210 to control the condensate flow to Flare Header. The Level Transmitter 304-LT-1209 has High-High and Low-Low level alarms 304-LAHH-1209 and 304-LALL-1209 respectively. For details, refer Cause & Effect Diagram 250-EPR-CNE0500. The gas from 304-V-001A enters the suction side of the Field Gas Compressor 304-K-001A. The suction pipe of 304-K-001A is provided with a temporary hose connection for nitrogen purging, during the start-up period. The suction pressure of the compressor is controlled by a self-regulating Pressure Control Valve 304-PCV-1294 which vents gas to Flare during the pressurized shutdown. Set pressure of 304-PCV-1294 above the settle out pressure. This PCV will be used to maintain pressure in the system during pressurized shutdown of the Compressor and not during normal operation. The compressor suction pressure is controlled by the Variable Speed Drive. The suction-side gas flow, temperature and pressure are
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 52 of 275
measured by 304-FI-1220, 304-TI-1222 and 304-PI-1221 which is also used for the anti-surge control of the compressor. Similarly the discharge pressure and temperature of the Compressor is indicated by 304-PI-1232 and 304-TI-1231 respectively. The compressed gas from the compressor discharge at a pressure of 87.5 barg and temperature of 166°C flows to the Field Gas Compressor Aftercooler-A (304-E-001A) where the temperature is cooled to 50C by Fin Fan Coolers. The compressed gas temperature is controlled by using 304-TIC-1215 which will control the Variable Speed Drive of the Fin Fan Motors. From the outlet of the Fin Fan Coolers, the gas is recycled to the suction of KO Drum 304-V-001A by the Antisurge Controller to minimise the surge. The compressed gas flows to the Gas Dehydration column through an ESD valve 304-XV-1219.
4.2.1.1
Compressor Auxiliary System
The Field Gas Compressor has two main auxiliary units – the Lube Oil system and the Seal Gas system. Auxiliary Lube Oil System The Lube Oil system comprises the following: Lube Oil Reservoir (304-T-1500), Lube Oil Heater (304-H-001A), Auxiliary Lube Oil Pump (304-P-002A), Main Lube Oil Gear Pump, Lube Oil Cooler (304-E-002A) and Lube Oil Filters 304-F-001A1/A2. During normal operation, the lube oil is supplied by the gear-driven main pump. The Auxiliary Lube Oil Pump is used during start-up, shutdown and also as a standby pump to main oil pump when the oil pressure is not adequate. The Lube Oil Reservoir level and temperature are indicated by Level Indicator 304-LI-1505 and Temperature Indicator 304-TI-1514 respectively. The Reservoir temperature is maintained by an
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 53 of 275
electric Heater which maintains the lube oil in the reservoir at a constant temperature. The temperature indicator 304-TI-1514 and level indicator 304-LI-1505 are provided with High and Low level alarms. The lube oil from the discharge of the Auxiliary/Main Lube oil pump is cooled in Lube Oil Coolers (304-E-002A) which are Air Fin Coolers. The lube oil header pressure is maintained at 2.5 barg by a Pressure Control Valve 304-PCV-1510 by regulating the lube oil back to the Lube Oil Reservoir. The lube oil is then filtered by Lube Oil Filters (304-F-001A1/A2) and distributed to the Motor and the Compressor (DE & NDE). The lube oil is supplied to the following items: o
Motor Bearings
o
Gearbox
o
Compressor (DE & NDE) bearings
The return lube oil flows to the lube oil reservoir through restriction orifices.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 54 of 275
Seal Gas System The Seal Gas provides the sealing media to the compressor seals. The dry gas seals consist of an inboard seal and an outboard seal. The inboard-seal seals between the process gas pressure inside the compressor and the pressure in the primary vent line. The outboard-seal seals between the primary and secondary vent line pressures. A schematic sketch of the Compressor Seal gas system is illustrated in Fig. 3 as given below: Fig. 3 – Schematic of Compressor Seal System
The primary seal gas from the discharge of the Compressor is filtered at the Seal Gas Filters 304-F-002A1/304-F-002A2. During Normal operation of the Compressor, Seal Gas is supplied from the Compressor Discharge. However, during the Start-up condition and Black-Start condition, bottled nitrogen will be used for the dry gas seal. In case of pressurized shutdown, the Settle-out Pressure is 46.4 barg. During this period, the seal gas supply can be supplied from the HP Fuel Gas tapped from the downstream (D/S) of Fuel Gas Heater (321-H-001A/B) to ensure dry heated gas supply to Dry Gas Seals. The suction pressure of the compressor is controlled by a self-regulating Pressure Control Valve 304-PCV-1294 whose set pressure is above the settle out pressure. This PCV will be used to maintain pressure in the system during pressurized shutdown of the Compressor and not during normal operation.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 55 of 275
Similarly, the Secondary Seal Gas is nitrogen gas, filtered in Buffer Gas Filters 304-F-003A1/A2. The Nitrogen (from Utilities) from the Buffer Gas Filters is split into two lines - one supplying as secondary seal gas through 304-PV-1465 and the other supplying seal gas through 304-PV-1449 for bearing separation seal. The leaking gas from the primary and secondary seal is vented to the Flare Header under Backpressure Controller 304-PCV-1464. The seal vent between the secondary seal and bearing separation seal is vented to the atmosphere at a safe location. 4.2.2 Field Gas Compressor Controls All control and safeguarding functions of the Field Gas Compressor and its auxiliaries will be controlled by Unit Control Panel (UCP) based control system, which consists mainly of PLC, Vibration and Displacement monitoring system and Human Machine Interface (HMI). All functions like the compressor start-up and shutdown sequence, anti-surge control, performance control, control and safeguarding of lube oil system, seal gas system, separation gas system, compressor bearings, motor bearings/purge unit/stator windings/cooling system, and, vibration and displacement monitoring system will be executed in the UCP. The compressor control system has interface with the plant DCS and ESD systems for monitoring, alarming and safe operation. It will also perform operations like Start-up sequence initiation, emergency stop, and manual operation of lube oil pumps and coolers from DCS. The various controls of Field Gas Compressor below relate to Compressor Train-A. Train-B is similar to Train-A, and hence not described separately. During Early Plant (HP) operation, all motor blocks and controllers related to Suction KO Drums, Compressors and After-coolers shall be disabled. Feed Gas Compressor Anti-Surge Control The anti-surge controller resides in the UCP. The process variable inputs to the antisurge controller and their related alarms will be conveyed to DCS over the serial link. The anti-surge control algorithm determines the compressor operating point relative to the surge limit/anti-surge control line, based on the following process variable inputs: o
Static pressure at the inlet and outlet of compressor: 304-PT-1221 and 304-PT-1232
o
Temperature at the inlet and outlet of compressor: 304-TT-1222 and 304-TT-1231
o
Flow into the compressor: 304-FT-1220
When the compressor approaches the anti-surge control line, the anti-surge controller will open the Anti-Surge Valve 304-FV-1212, located on the compressor recycle line, to prevent surge. When the compressor is running and well above the surge control line, the anti-surge valve is closed. The various modes of the anti-surge controller are listed below: o
In normal operation, the anti-surge controller is in AUTO
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
o
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 56 of 275
During compressor start-up and shutdown sequence, the controller is forced in ‘SEQUENCE’ and the anti-surge valve opens
o
The anti-surge controller can be manually operated to open or close the anti-surge valve from the UCP HMI (Human-Machine Interface). However, if the compressor operating point approaches the anti-surge control line, the controller is switched back to Auto mode automatically.
Performance Control – Suction Pressure Controller The compressor performance is controlled by the Compressor Suction Pressure Controller. Compressor suction pressure is measured by 304-PT-1221. The suction pressure controller sends a speed set-point signal to the Variable Speed Drive System (VSDS). Speed variation up to 80% is only possible. The Performance Controller is present in the UCP and can be operated when in Local mode. However the Performance Controller can also be operated from DCS when selector is in Remote mode. For Compressor discharge pressure limiting, a discharge pressure Over-ride Controller is provided. If the Compressor discharge pressure increases above its set point, the Discharge Pressure Over-ride Controller over-rides the Suction Pressure controller when the output of the Over-ride Controller is below the output of the Suction Pressure Controller. The set point of the over-ride controller is fixed and written in the PLC (UCP). However the set point for the Suction Pressure Controller can be adjusted from the UCP HMI as well as from the DCS panel depending on the position of the Local/Remote switch. When the switch is in ‘Remote’ position, following operations from DCS is possible: o
DCS set point is written to the Controller (DCS shall ‘track’ the controller set point when in ‘local’). The controller shall send the set point, as an analog value, back to the DCS for display of ‘set point’ on the DCS Controller faceplate.
o
Controller can be switched from AUTO to MANUAL, by sending a pulsed command from DCS to UCP. The controller shall send a confirmatory pulse back to the DCS for display of ‘AUTO/MANUAL’ on the DCS faceplate.
o
In MANUAL, the output of the valve can be manipulated from the DCS. The DCS requested valve position, which is an analog signal, is written to the controller.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 57 of 275
The controller shall send the valve position, as an analog value, back to the DCS for display of ‘valve position’ on the DCS faceplate. The VSDS tends to decrease the speed of the compressor in case the suction pressure is decreasing below the set point. The various modes of the Compressor Suction Pressure Controller are listed below: o
In normal operation, the suction pressure controller is in Auto, the discharge pressure over-ride controller shall be in Track.
o
During Compressor start-up and shutdown sequence, the Suction Pressure Controller is forced in ‘SEQUENCE’.
o
The Suction Pressure Controller can be manually operated to increase or decrease the compressor speed from the UCP HMI and the DCS. However, switching from Auto to Manual is only possible when the controller is in Auto and not in Track.
Compressor Lube Oil System All control, safeguarding, start-up and shutdown sequence concerning the compressor lube oil system is implemented in UCP. However lube oil coolers and pumps can be started and stopped from the DCS. The lube oil reservoir temperature is controlled by an electric heater with thermostat switch. The Lube Oil Reservoir temperature is controlled by 304-TC-1527 which controls the heater by a thermister control which switches the heater ON and OFF at a desired temperature. The lube oil header temperature is maintained at 59°C by a temperature controller acting on a Three-Way Valve 304-TCV-1503 which bypasses the lube oil across the Lube Oil Cooler (304-E-002A). The lube oil supply pressure is controlled by self-actuated Pressure Control Valve 304-PCV-1510 which maintains the header pressure at 2.5 barg by opening to the Lube Oil Reservoir. At start-up, the Lube Oil Cooler Fans need to be started before the Lube Oil Pump. A minimum of two fans shall be started. This can be done from the UCP HMI as well as from the DCS. Before the standby lube oil pump can be started, the lube oil temperature shall be above 10C and the separation gas shall be applied. The start-up permissive are built in the PLC (UCP). The Standby Lube Oil Pump is automatically stopped after the gear-driven main pump is running and maintains the header pressure above 2.5 barg. Seal Gas and Separation Gas System The dry gas seal consists of an inboard and an outboard seals. The inboard-seal seals between the process gas pressure inside the compressor and the pressure in the primary vent line. The outboard-seal seals between the primary and secondary vent line pressures. The primary vent pressure is controlled such that there is always some flow through the inboard seal and the outboard seal for cooling purposes. 304-PIC-1464 controls the primary vent pressure by throttling the Control Valve 304-PCV-1464 located on the primary vent to flare system. The secondary seal gas (N2) is supplied at controlled pressure by 304-PIC-1465. The secondary seal gas (N 2) is supplied to the barrier seals to prevent lube oil carry-over to the seal area and vice versa. This is
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 58 of 275
provided via a self-acting pressure regulator 304-PV-1449. These controllers are integrated in PLC and have no DCS control. The following shutdown conditions of Seal Gas & Lube Oil cause Unit Shutdown with Blowdown:
o
Primary seal vent pressure NDE – Low-Low
o
Primary seal vent pressure NDE – High-High
o
Primary seal vent pressure DE – Low-Low
o
Primary seal vent pressure DE – High-High
o
ESD1 (trip with blowdown)
o
ESD button compressor skid
o
ESD button on UCP (unit control panel)
o
UCP critical failure
However the ESD3 (recycle trip) causes unit shutdown in recycle mode, whereas all other shutdown conditions cause unit shutdown without blowdown. Refer Siemens Cause & Effect diagram (HE612428200) Compressor Sequencing Compressor start-up and shutdown sequence is built in the PLC (UCP). The Start-up sequence can be started in Manual mode in step-by-step sequence or the sequence can be stopped from the DCS. The status of various stages of the sequence shall be displayed in the DCS graphics. During normal operation when the compressor is running, all the controllers are in Auto. Before initiating the start-up sequence, all trips have to be cleared and all the start-up interlocks have to be fulfilled. When all systems are healthy, the compressor will be pressurized. The casing and seal cavity shall be drained before every start-up, which is a manual activity and upon completion, will be conveyed from DCS to the PLC as a pulse command. The compressor is started with an open anti-surge valve. Once the motor is running at minimum speed, the compressor can be loaded; the anti-surge and performance controllers will be switched from SEQUENCE to AUTO. When the compressor is stopped, the anti-surge controller is switched to SEQUENCE, the anti-surge valve is force-opened and the compressor is brought to a standstill in the pressurized state. The motor will stop within a predefined time. ESD trip with or without blowdown shall be as per the conditions given in supplier’s C&E diagram, document no. JI-190-C02411-EMR-D16-002. Also refer C&E diagram 250-EPR-CNE-05001.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 59 of 275
Compressor Suction KOD Level Control The level of the collected condensate in 304-V-001A is controlled by a level-indicating Controller 304-LIC-1210 which acts on 304-LV-1210 connected to a Flare Header. The Level Controller works on Gap Control philosophy which opens the Level Control Valve at the high level setting of 304-LIC-1210 and continues to remain open till it reaches the Low level setting of 304-LIC-1210. The valve continues to be in closed condition until the level again reaches the High level set value. Field Gas Compressor Aftercooler Temperature Control Field Gas Compressor Aftercooler 304-E-001A has two bays, each bay comprising of a Variable Speed Drive (VSD) driven fan, a Fixed Speed fan and three sets of Louvers. The outlet temperature is controlled by 304-TIC-1215, which controls the speed of the VSD driven fans and also implements an ‘ON-OFF’ control of the fixed speed fans. During periods of low ambient temperature, fixed speed fans will be automatically turned off to ensure a steady outlet temperature of 50C and the VSD driven fans reach their lowest controllable speed. 304-TICA-1268 and 304-TICA-1275 control the set of louvers of the respective bay. The VSD driven fan speed is controlled by the continuous control from 304-TIC-1215. In case of temperature increasing above the set point, the controller output also increases. 304-TIC-1215 output is simultaneously given to both the VSDs, such that the two fans always run at same speed. The fixed speed fan is controlled as follows. In case 304-TIC-1215 output rises above the high set point (configurable), a ‘START’ command is send to PMS to start both the fan motors simultaneously. The motors continue running till the temperature falls below the low set point (configurable), when the controller sends a ‘STOP’ command to stop both the fan motors simultaneously. The motor remains stopped till the temperature re-attains the high set point and the cycle will continue. Thus, at all times the two fans are either running or stopped. ‘START’ and ‘STOP’ commands are sent from DCS to PMS over serial link. Motor ‘fault’, ‘tripped on ESD’, ‘available/not available’, ‘running/stopped’ and ‘VSD trouble’ (only for VSD drives) feedbacks shall be available to DCS from PMS over serial link. Fixed speed motor can be started or stopped by the operator in ‘Manual’ from the DCS HMI. Auto/Manual logic for the fans resides in CMS. Variable speed motor shall be started by the operator from the DCS, always forced in ‘Manual’. When the ‘START’ command is sent from DCS to VSD, VSD shall start and ramp up to the speed as per 304-TIC-1215 output. The operator can manually modulate the fan speed by switching the controller in ‘Manual’. If the VSD trips from ESD or is stopped from DCS, the controller output is forced to 0% and switches to ‘Manual’ mode. The bay-1 and bay-2 louvers Tilt Angles are controlled by the continuous control from 304-TICA-1268 and 304-TICA-1275 respectively. In case of temperature increasing above the set point, the controller output increases. 304-TICA-1268/75 output is
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 60 of 275
simultaneously given to all the three louvers, such that the three louvers of the same bay always have the same tilt angle. If temperature at outlet of Air Cooler goes below the set point, first VSD driven fan reduces speed. When it reaches to minimum speed, fixed speed fan is switched off and VSD fan increases up to the requirement. Louver is operated based on intake air temperature controller. The set point of air temperature controller is above hydrate formation temperature and louver control will come only when air temperature drops below the set point value. Early Plant (HP) Operation During this mode, the suction KO Drums, the Field Gas Compressors and their Aftercoolers will be bypassed. Hence, all controllers, as listed below, related to the suction KO Drums, the Field Gas Compressors and the Aftercoolers shall be forced to ‘Manual’ and outputs driven to 0% during HP mode operations. 304-TICA-1268 304-TICA-1275 304-TICA-1215 304-LIC-1210 304-TICA-1368 304-TICA-1375 304-TICA-1315 304-LIC-1310
Field Field Field Field Field Field Field Field
Gas Gas Gas Gas Gas Gas Gas Gas
Compressor Aftercooler-A louver control (bay-1) Compressor Aftercooler-A louver control (bay-2) Compressor Aftercooler-A outlet temperature control Compressor Suction KO Drum-A level control Compressor Aftercooler-B louver control (bay-1) Compressor Aftercooler-B louver control (bay-2) Compressor Aftercooler-B outlet temperature control Compressor Suction KO Drum-B level control
In addition to the above, the compressor faceplate for DCS operations like compressor start sequence, compressor motor start, lube oil standby pump start and lube oil coolers start shall be disabled during HP mode. 4.3
CONDENSATE SYSTEM
4.3.1 PROCESS DESCRIPTION The condensate from the Production Separator (302-V-001) is pumped by Condensate Pumps 302-P-001A or 302-P-001B during the LP Phase operation whereas the Early Operation Condensate Pumps 302-P-002A and 302-P-002B will be in line during the HP phase. During the LP phase, the Minimum-flow Controller 302-FIC-1130 installed on the discharge side of the Condensate Pumps protects the pump by operating the Minimum-flow Controller Valve 302-FV-1130. During HP phase, the Level Controller 302-LIC-1119A controls the Level control valve 302-LV-1119. During normal operation (LP Phase) one condensate pump will be running and Standby pump will start automatically in case the duty pump trips. This protection is provided for both the Condensate Pumps and the Early Operation Condensate Pumps. The condensate from the discharge of the Condensate Pumps flows through Condensate Solid Filters (302-F-001A/B). The Condensate Filters will remove 100% of 25-micron particle size and above, and remove 90% of 20-micron particle size and above. One filter will be on
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 61 of 275
line and the differential pressure across the filter 302-F-001A is measured by 302-PDI-1146; 302-PDI-1144 measures the differential pressure for 302-F-001B filter. As the differential pressure of the filters increases, alarm will sound and the filter will be isolated and changed to the standby filter. There are two Safety Relief Valves 302-PSV-105 and 302-PSV-106 set at a pressure of 142 barg which opens to the Flare Header. The Condensate from the Condensate Filters flows to the Condensate Coalescer 302-F-002A/B where water from the Condensate is removed. The Coalescer is designed for inlet water content of 1% by volume and the outlet water content should be less than 200 ppm. The Interface levels of Coalescer 302-F-002A/B are measured by Level Transmitters 302-LT-1156A&B respectively. One Coalescer will be on line and the differential pressure across the Coalescer element 302-F-002B is measured by 302-PDI-1168 and 302-PDI-1169 measures the differential pressure for 302-F-002A. At high differential pressure alarm of the Coalescer, the Coalescer will be isolated and changed to the standby Coalescer. There are two Safety Relief Valves 302-PSV-107 and 302-PSV-108 set at a pressure of 142 barg and the blowdown is connected to the Flare Header.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 62 of 275
CONDENSATE PUMPS Equipment Tag No. Type Fluid Description Temperature Suction Pressure Discharge Pressure Flow Density of Liquid at WPT Viscosity of Liquid at WPT Motor Power Material of Construction Seal Type
302-P-001A/B Centrifugal Hydrocarbon Condensate Rated 36.0 26.2 95.0 24.5 661 0.33 202 Casing: Duplex Stainless Steel Impeller: Duplex Stainless Steel Mechanical
Unit ºC bara bara m³/h kg/m³ Cp kW
CONDENSATE COALESCER Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Liquid Quantity Density at WPT Material of Construction
302-F-002A/B Coalescer Vessel Condensate Maximum –28.0 142.0 8.0 87.3 36.7 0.650 Shell: Carbon Steel Cladding: Duplex SS
Minimum 82.0 — 41.1 —
Unit ºC barg ºC barg M3/h Kg/m3
Minimum 82.0 — 41.1
Unit ºC barg ºC barg m3/h kg/m3
CONDENSATE SOLIDS FILTER Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Liquid Quantity Density at WPT Material of Construction
302-F-001A/B Filter – Catridge Condensate Maximum –28.0 142.0 8.0 87.9 36.7 0.650 Shell: Carbon Steel Internals: Duplex SS Cladding: Duplex SS
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 63 of 275
EARLY OPERATION CONDENSATE PUMPS Equipment Tag No. Type Fluid Description Temperature Suction pressure Discharge pressure Flow Density of Liquid at WPT (Rich Winter/Lean Summer) Viscosity of Liquid at WPT (Rich Winter/Lean Summer) Motor Power Material of Construction Seal Type
302-P-002A/B Rotary Progressive Cavity Type Hydrocarbon Condensate Rated 41 87.4 98.2 36.6
Unit ºC bara bara m³/h
664.5/554
kg/m³
0.18/0.307
Cp
40.56 Casing: Duplex Stainless Steel Impeller: Duplex Stainless Steel Mechanical
kW
4.3.2 Condensate System Control The interface levels of Coalescer 302-F-002A/B are measured and controlled by Transmitters 302-LT-1156A/B respectively. The coalescer LT for duty is selected through a duty/standby selector switch 302-LHS-1156. The Produced Water level is controlled by Level Controller 302-LIC-1156 which controls 302-LV-1156 located on the Produced Water outlet line. The dry condensate from the Condensate Coalescer is injected into the dry gas from the Gas Dehydration Column 305-C-001 and the mixed fluid is routed to GTP through a 76 km trunk line. 4.3.2.1
Normal Operation (LP) Mode
During LP mode, the Condensate pumps are protected against low flow by the Minimum-Flow Control Valve 302-FV-1130 operated by Controller 302-FIC-1130, which shall be forced to ‘Manual’ and output driven to 0% under the following conditions: o
Plant in Early Operation (HP) mode
o
Both condensate pumps 302-P-001 A and B are stopped
4.3.2.2
Early Operation (HP) mode
During HP mode, Production Separator Condensate Level Controller 302-LIC-1119A, which takes the same measurement as 302-LIC-1119, controls the separator level by operating the Level Control Valve 302-LV-1119 at the Condensate Pump (302-P-002A/B)
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 64 of 275
recycle line. The Early Operation Condensate Pumps are Positive displacement Pumps and works on back pressure. Trunk line operating pressure varies from 68.2 Bara (during turndown operation) to 86.2 bara (during normal Plant Operation). During HP mode of operation, Production Separator pressure is 87.0 bara. Hence during the HP mode of operation, there are chances of operating 302-P-002A/B at very low differential pressure. 302-PIC-1132 will maintain certain differential pressure for 302-P-002A/B by throttling 302-FV-1182 using output from 302-PIC-1132. 302-LIC-1119A shall be forced to Manual mode and output driven to zero under the following conditions: o
Plant in ‘Normal Operation’ (LP) Mode
o
Both condensate pumps 302-P-002A and B are ‘Stopped’
Dry Condensate to Export – Flow Control 302-FIC-1182 controls the dry condensate to export flow by throttling the Control Valve 302-FV-1182 on the dry condensate export line. 302-FV-1182 tends to open in case of dry condensate flow decreasing below the set point. Over-ride: Dry condensate flow control will be overridden by condensate pump discharge pressure 302-PIC-1132. This shall be achieved by using a ‘Low Signal Selector’ block, which will select the lower of 302-FIC-1182 and 302-PIC-1132. The selected controller output will act on 302-FV-1182. 4.3.3 Condensate Coalescer Interface Level Control The Level Selector Switch 302-LHS-1156 selects either of the Condensate Interface level 302-LIC-1156A or 302-LIC-1156B in operation and will control 302-LV-1156 on feed to Produced Water Degassing tank 334-V-001. For details refer Cause and Effect diagram 250-EPR-CNE-05001 4.4
GAS DEHYDRATION SYSTEM
4.4.1 Process Description The solvent used for the removal of water is Tri-Ethylene Glycol (TEG). After absorption of water, the rich TEG is regenerated in TEG Regeneration system and recycled back to the Dehydration Column as Lean TEG. The mass transfer is achieved by a packing column where the lean TEG is counter-currently contacted with wet gas. The wet gas from the Feed Gas Compressor at a pressure of 87 barg and temperature of 50C enters the Gas Dehydration Column (305-C-001). During the HP case, when the Well head pressure is high enough, the Feed Gas Compressor system is totally bypassed and joins the inlet of the Gas Dehydration Column. The wet gas enters the bottom section of the Column. It flows into the Inlet Scrubber section of the Column where any entrained liquid is removed before the gas is introduced into the dehydration section of the contactor. All the liquids (condensate hydrocarbons or liquid water) recovered in the bottom of the inlet scrubber are drawn down under level control and drained to Flare Drum through a Check Valve, ESD Valve 305-XV-3001 and a Level Control Valve 305-LV-3013 during HP mode of operation. During LP operation, the condensate is returned to the Production Separator. There are two Level Transmitters,
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 65 of 275
one for bottom level control of condensate in the inlet scrubber 305-LT-3013 and the other for ESD control 305-LT-3015. For the effects of 305-LAHH-3015 and 305-LALL-3015, refer Cause & Effect Diagram 250-EPR-CNE-05001. The inlet gas separation device allows a large gas flow turndown while assuring even gas distribution. The gas separation device (vane type) uses curved plates to disperse all inlet gas evenly beneath a wire mesh Mist Eliminator and to separate gas and liquid efficiently. The purpose of the mist eliminator is to coalesce the condensate droplets from the gas stream. The gas then flows through the gas risers of the glycol chimney tray, which allows a uniform distribution of the gas before it enters in the gas/glycol contacting section. The structured packing in the Gas Dehydration Column is to ensure uniform distribution and contact between the liquid and the vapour. There are two level transmitters 305-LT-3017 which control the rich TEG level and 305-LT-3016 for trip purpose. There are High-High and Low-Low level alarms 305-LAHH-3016 and LALL-3016, the effects of which are detailed in Cause & Effect Diagram 250-EPR-CNE-05001. The lean glycol from the discharge of Glycol Circulation Pumps (305-P-003A/B) enters at 55C in order to have a contact temperature of 10C above the wet gas inlet temperature. The lean glycol enters at the top of the column and is equally distributed over the whole section of the column by the Glycol Distributor installed above the packed bed. The dehydration by absorption takes place as the gas flows upwards through the packing, contacting the wetted surface of the packing. A high efficiency Demister removes entrained glycol droplets from the dehydrated gas stream before it leaves the top of the contactor. The dehydrated gas from the top of 305-C-001 enters Dry Gas/Lean TEG Heat Exchanger (305-E-004) where the lean TEG is cooled to maintain the difference of 5 to 10C between the lean TEG and wet gas (entering the dehydration column). The rich TEG comes down the structured packing after absorption of moisture and is sent to TEG Regeneration system. There are two Safety Relief Valves 305-PSV-119A and 305-PSV-119B which are set at a pressure of 95.2 barg provided on the top of 305-C-001 which will release to Flare header during over-pressurization of Dehydration Column. The differential pressure across the packed column is monitored by Differential Pressure Transmitter 305-PDI-3007 and sounds a high differential pressure alarm when the pressure reaches the alarm set point. The higher differential pressure across the contactor indicates foaming in the Contactor. There are high-pressure and low-pressure alarm set points indicated by 305-PAL-3009 and 305-PAH-3009. The flow of dehydrated gas from the outlet of 305-E-004 is measured by 305-FI-3006. At the downstream of ESD Valve 305-XV-3004, the dry condensate from Coalescer and the dehydrated gas are mixed and transferred to GTP through the trunk line. There are methanol injection points ME-711 and ME-713 on the top vapour lines. There is a Moisture Analyzer 304-AI3022 which measures the moisture content of the dehydrated gas. The analyser is provided with High alarm and High-High alarm set at 1.3 lb/MMSCF and 1.5 lb/MMSCF respectively.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 66 of 275
GAS DEHYDRATION COLUMN Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Liquid- Flow Density at WPT Vapour Quantity Molecular Weight Density at WPT Structured Packing
Material of Construction
Dimensions: OD Length (T/T)
305-C-001 Packed Column Hydrocarbon Gas & TEG Maximum Minimum Unit 82 –15 ºC 95.2 — barg 12.5 55 ºC 67.2 85.2 barg 6201 kg/h 1100 kg/m3 97980 kg/h 19.28 20.66 kg/m3 4600 mm Top Shell: A516 Gr7 ON Bottom Shell: A516 Gr7ON + 3mm SS-316L Cladding: Internals: A516 Gr 70 Cladding: 3 mm SS-316L Bottom: 1714;Top: 1494 Mm 12600 mm
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 67 of 275
Fig. 4 – Gas Compression and Gas Dehydration
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 68 of 275
4.4.2 Gas Dehydration Controls 4.4.2.1
305-C-001 Pressure Control
Under normal operation, the Dehydration Column (305-C-001) pressure is governed by the pressure losses in the downstream trunk line up to the GTP facility. However, to prevent a low pressure occurring in the contactor during low flow or upset conditions, 305-PIC-3009 will control the column pressure by throttling 305-PV-3009A and 305-PV-3009B in split control. Under normal conditions, the Full-Bore Valve 305-PV-3009A on the dry gas line and 305-PV-3009B located in parallel to 305-PV-3009A remain fully open. In case of very low pressure, i.e. when the dry gas pressure falls below the set point, 305-PV-3009A fully closes and the gas is routed via 305-PV-3009B, to elevate the pressure in the gas dehydration column. The minimum pressure to be maintained in dehydration column is 68.2 bara during the turn-around operation. The Split range control valve is illustrated as given below in Fig. 5: Fig. 5 – Split Range Control
During the start-up phase, the pressure is controlled by Pressure Controller 305-PIC-3024 which opens to flare by operating 305-PV-3024 which acts as a spill-off control valve as well to dump gas to the flare system upon detection of high pressure.
4.4.2.2
305-C-001 Rich TEG Level Control
The rich TEG after the absorption of water is routed to TEG Regenerator system by level control. The Rich TEG level is controlled by a Level Controller 305-LIC-3017 which controls 305-LV-3017 to TEG Regenerator system.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
4.4.2.3
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 69 of 275
305-C-001 Bottom Level Control
All the liquids (condensate hydrocarbons or liquid water) recovered in the bottom of the Inlet Scrubber are drawn down under level control and returned to the Production Separator/Flare during LP/HP Mode. 305-LIC-3013 controls the bottom level of the Inlet Scrubber. It is a Gap Controller which has On/Off action on Control Valve 305-LV-3013 through which the knocked out condensate liquid is returned back to the inlet of Production Separator during LP mode operation. During HP mode operation, all liquid recovered in the bottom of dehydration column is routed to flare.
4.5
TEG REGENERATION SYSTEM
4.5.1 Principle of TEG Regeneration System The rich glycol from the Gas Dehydration Column bottom needs regeneration to reclaim its initial characteristics, before its re-use. This is achieved in the TEG regeneration system, where water is separated from the rich glycol by fractionating the rich solution at a high temperature. The rich glycol after absorption of water leaves the contactor on level control. It first flows through the Reflux Condenser in the top of the Regeneration Still Column, thereby providing reflux cooling in the Reflux Condenser. A simplified sketch of TEG Regeneration system is given below in Fig. 6.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 70 of 275
Fig. 6 – TEG Regeneration System
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 71 of 275
The rich glycol is then heated to about 60C or 70C in the Cold Lean/Rich Glycol Heat Exchanger before entering the Glycol Flash Vessel (operating pressure is 4 barg). In this 3-phase separator, dissolved and entrained gases flash off and are removed from the glycol. Liquid hydrocarbon condensate, if present, is also separated from the glycol. If not separated off, these hydrocarbon components would flash in the Regenerator and lead to an increased still-column vapour load, a higher reboiler duty requirement, greater glycol losses and a loss of recoverable product. These components could also lead to coking of the reboiler heating elements, fouling, foaming and a higher BTEX level in the water condensed from the overhead condenser. While this arrangement is typical, in some units the Glycol Flash Vessel is located immediately downstream of the contactor, operating at a lower temperature. From the flash vessel the rich glycol flows through a full flow particle filter and an activated carbon filter often in slipstream service, to remove solids and dissolved hydrocarbons and degradation products, respectively. The rich glycol is further heated in the LP rich/lean glycol heat exchanger and then flows to the regenerator still column where it enters between two contacting sections. Heat is provided at the bottom of the regenerator in order to evaporate water from the glycol. The reboiler may be directly fired or indirectly heated by electricity, hot oil or steam. Typical operating temperatures for TEG are up to 204°C. Water and volatile species present are evaporated from the rich glycol, and reflux is provided to reduce glycol losses. Because of the wide difference in volatility, only a small reflux is needed to effect water/glycol separation. The regenerated hot lean glycol leaves the Reboiler, flows through the stripping column and collects through the TEG surge drum. GLYCOL CIRCULATION PUMPS Equipment Tag No. Type Fluid Description Temperature Suction Pressure Discharge Pressure Flow Density of Liquid at WPT Viscosity of Liquid at WPT Power Absorbed at Shaft Material of Construction
305-P-003A/B Reciprocating Lean TEG 99.9% Rated 101.6 0.11 96.8 6.0 1046 3.73 15.8 Casing: AISI 316L; Impeller: AISI 316 L
Unit ºC barg barg m³/h kg/m³ Cp kW
TEG BURNER AIR FAN Equipment Tag No. Type Fluid Description Temperature
305-K-001A/B Centrifugal Blower Air Rated 25
Unit ºC
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Equipment Tag No. Suction Pressure Discharge Pressure Flow Motor Power Material of Construction
Operations Page 72 of 275
305-K-001A/B ATM barg 96.8 m barg 1500 Nm³/h 4.0 kW Casing: AISI 316 L; Impeller: AISI 316 L
TEG MAKE-UP FILTER Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Liquid Quantity Density at WPT Material of Construction Dimensions
305-F-001 Catridge Lean TEG Maximum 82.0 10.0 45.0
Minimum –15.0 — –4.0
3.3 5.0 1104 Shell: KCS; Internals: SS316L 203.2 ID x 1500 TT length
Unit º C barg ºC barg m3/h kg/m3 mm
TEG DRAIN VESSEL Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Material of Construction Dimensions: ID Length (T/T)
305-V-001 Horizontal vessel TEG Maximum Minimum –15.0 82.0 3.5 — –15.0 45.0 0.005 1.5 Shell & Heads: CS 2000 7700
Unit ºC barg (kPa) ºC barg (kPa) mm mm
TEG STRIPPING COLUMN Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure
305-C-001 Packed Column Hydrocarbon Gas & TEG Maximum Minimum 280.0 –15.0 3.5 FV 204.0 0.12
Unit ºC barg (kPa) ºC barg (kPa)
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Equipment Tag No. Liquid Flow Vapour Quantity Structured Packing Material of Construction Dimensions:
OD Length (T/T)
Operations Page 73 of 275
305-C-001 0.8 160.2 Pall Rings 5/8” -1900 mm Shell & Heads: ASTM A516 Gr60 Internals: Pall Rings 5/8” SS316L 406.4 1900
kg/h kg/h mm
mm mm
TEG DRAIN PUMP Equipment Tag No. Type Fluid Description Temperature Suction pressure Discharge pressure Flow Density of Liquid at WPT Viscosity of Liquid at WPT Motor Power Material of Construction
305-P-001 Vertical Sump Pump Lean/Rich Glycol Rated 45 0.22 2.08 5 1100 57.26 5.5 Casing: SS 316 L; Impeller: SS 316 L
Unit ºC bara bara m³/h kg/m³ Cp kW
TEG STORAGE TANK Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Operating Capacity Density at WPT Dimension Material of Construction
305-T-001 Tank TEG Maximum –15.0 180.0 0.0
Unit ºC mbarg ºC 20.0 mbarg 28.0 m3 1100 kg/m3 4000 ID x 3000H mm Shell/Bottom: Carbon Steel; Internals: SS 316L
TEG MAKE-UP PUMP Equipment Tag No. Type Fluid
305-P-002 Centrifugal Pump Lean TEG
Minimum 82.0 –2.5 45.0
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Description Temperature Suction Pressure Discharge Pressure Flow Density of Liquid at WPT Viscosity of Liquid at WPT Motor Power Material of Construction
Operations Page 74 of 275
Rated 45 0.5 5.56 5.0 1100 40 5.5 Casing: KCS; Impeller: KCS
Unit ºC bara bara m³/h kg/m³ Cp kW
COLD LEAN/RICH GLYCOL HEAT EXCHANGER Equipment Tag No. Type Fluid Description Design Temp – Plate Operating Temp – Plate Design Pressure – Plate Design Temp – Shell Design Pressure – Shell Operating Temp – Shell Fluid Plate Fluid Shell Heat Duty Material of Construction
305-E-001 Plate Type Heat Exchanger Plate: Lean Glycol; Shell: Rich TEG Maximum Minimum 240.0 –15.0 Inlet: 120.0 Outlet: 73.0 10.3 –1.0 180.0 –15.0 10.3 –1.0 Inlet: 12.0 Outlet:62.0 6201.0 6360.0 204.0 Plate: SA240 316; Shell: SA333 Gr6
Unit ºC ºC barg ºC barg ºC kg/h kg/h kW
HOT LEAN/RICH GLYCOL HEAT EXCHANGER Equipment Tag No. Type Fluid Description Design Temp – Plate Operating Temp – Plate Design Pressure – Plate Design Temp – Shell Design Pressure – Shell Operating Temp – Shell Fluid – Plate Fluid – Shell Heat Duty Material of Construction
305-E-002 Plate Type Heat Exchanger Plate: Lean Glycol; Shell: Rich TEG Maximum Minimum 240.0 –15.0 Inlet :194.0 Outlet :103.0 10.3 –1.0 180.0 –15.0 10.3 –1.0 Inlet: 62.0 Outlet: 150.0 6201.0 6462.0 410.0 Plate: SA240 316; Shell: SA333 Gr6
Unit ºC ºC barg ºC barg ºC kg/h kg/h kW
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 75 of 275
4.5.2 Process Description After contacting the wet gas, the water-rich glycol (Rich TEG) is regenerated by heating at approximately atmospheric pressure to a temperature high enough to drive off almost all the absorbed water. The regenerated lean glycol is then cooled and re-circulated back to the Gas Dehydration Column (305-C-001). The rich TEG from the 305-C-001 Chimney Collection Tray flows on level control through 305-LV-3017 to the bottom shell side of TEG Reflux Condenser (305-E-003). The rich TEG is heated from 53.7C to 62C by hot glycol vapours generated from the TEG Reboiler (305-H-001). Then the rich glycol is preheated in the Cold Lean/Rich Glycol Exchanger (305-E-001) to 68C in order to achieve the proper temperature for good separation efficiency before entering the Glycol Flash Drum (305-V-002). The Glycol Flash Drum, operating at 4 barg, is a horizontal 3-phase separator which separates the hydrocarbon liquid phase from the glycol phase and vents any remaining gases. The Glycol Flash Drum consists of 3 compartments: the inlet settling compartment, the hydrocarbon (HC) bucket and the glycol outlet compartment. The Glycol Flash Drum is designed for a fixed liquid retention time in the settling compartment for adequate separation of entrained liquid hydrocarbons. The rich glycol leaves the Glycol Flash Drum at 68C, and passes through the Rich TEG Cartridge Filters (305-F-003A/B). Here the rich TEG is purified from eventually entrained solid particles and the remaining hydrocarbons are removed by the TEG Carbon Filter (305-F-002). The rich TEG from the Carbon filter enters the Hot Lean/Rich Glycol exchanger (305-E-002) where it is preheated from 68C to 150C. The rich TEG is fed from the Glycol Flash Drum under level control by 305-LIC-3210 and is distributed on the middle of TEG Still Column (305-C-002). The heat for the distillation is given by hot TEG vapours from the TEG Reboiler (305-H-001). After reboiling, the hot TEG vapours and water move up the TEG Still Column stripping out the water from the rich TEG moving counter currently down the TEG Still Column. The Reboiler Regeneration temperature is maintained at 204C and the fire/fume tubes are designed in order to avoid hot spot with consequent TEG degradation and to reduce the glycol losses to unavoidable minimum. Once the TEG has left the heating section, it reaches a purity of 99.0 wt% and it flows inside the Stripping Column (305-C-003). The TEG Reboiler is a direct-fired Reboiler with a burner assembly burning fuel gas and oxygen in slightly above the stochiometric quantities. The burnt combusted flue gases pass through the U-tube assembly and are finally released to atmosphere at a high elevation stack. The fuel gas required for burning in the Reboiler is first heated in the TEG Surge Drum (305-V-005) and then passed through Fuel Gas KO Drum (305-V-004) to remove any condensate. Then it is passed through Filter Coalescer and burnt in the Burner Assembly of 305-H-001. The fuel gas pressure to the burner assembly is controlled by a self-regulating Pressure Controller 305-PCV-3175 set at 0.5 barg. The primary air required for combustion is supplied by Burner Air Fan (305-K-001A/B). In the U/S of 305-PCV-3175 a 2” line is taken and pre-heated in 305-H-001 and sent to 305-V-005 as stripping gas for 305-V-005. In the Stripping Column, in order to achieve the desired purity of 99.9 wt% of lean TEG purity, fuel gas as external stripping gas is used. The intimate contact of Glycol and stripping gas is ensured by a Pall-ring packing. The regenerated glycol is
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 76 of 275
collected in the TEG Surge Drum (305-V-005). The regenerated glycol coming from the Surge Drum (305-V-005) is cooled down from 193.6C to 109.6C in the hot Lean/Rich Glycol Heat Exchanger (305-E-002) and then passes through the Cold Lean/Rich Glycol Exchanger (305-E-001) where the outlet temperature reaches 103°C. The pressure is increased to 88.5 bara by means of Glycol Circulation Pumps (305-P-003A/B). The glycol-water vapours move up the TEG Reflux Condenser (305-E-003), on the tube side, cooled by the rich TEG from 305-C-001 on the shell side. In the TEG Reflux Condenser, the glycol vapours are condensed and predominantly water vapour along with little uncondensed TEG escapes. The vapours from the outlet of TEG Reflux Condenser go to Vent Gas KO drum (305-V-003) from where the condensed liquid is sent to Closed Drain System. The uncondensed vapour from the top of 305-V-003 goes to a Vent Gas Blower (305-K-001A/B & 305-K-001C/D) which operates in series. The vent gas flows to the TEG Incinerator where the vapours are burnt with air. Provision is given to route the off-gas to Flare when the Incinerator is not available. The hot TEG is distilled by the removal of water from the rich TEG. The hot TEG vapours from the TEG Reboiler (305-H-001) provide the heat input for the distillation of rich TEG into lean TEG and water. The lean Glycol is pumped by Glycol Circulation Pump (305-P-003A/B) and passes through the Dry Gas/Lean TEG Exchanger (305-E-004) before entering the Dehydration Column (305-C-001) through a flow distributor. The required make-up TEG is pumped from the TEG Storage Tank (305-T-001) by TEG Make-up Pump (305-P-002) and it flows through a TEG Make-up Filter (305-F-001). The TEG Storage Tank (305-T-001) is a conical fixed roof storage tank maintained at a pressure of 80 mbarg with a nominal capacity of 28 m3. The tank pressure is maintained by a self-regulating Pressure Control Valve 305-PCV-3049 by controlling blanket nitrogen to tank. If the tank gets over-pressurized, then it is opened to atmosphere through a vent by a self-regulating Pressure Control Valve 305-PCV-3048. The drain from the various vessels of Gas Dehydration system and TEG Regeneration system is drained into TEG Drain Vessel (305-V-001). From 305-V-001 it is pumped back to the Regenerator system using TEG Drain pump. A Pressure Vacuum Valve 305-PVV-161 is fitted to the tank which will open at a pressure of 140 mbar and at a vacuum of –1 mbarg. 305-PVV-161 acts as a safety device to prevent the tank during the failure of 305-PCV-3048 or 305-PCV-3049.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 77 of 275
4.5.3 TEG Regenerator Controls The TEG regeneration package has the following control loops. Glycol Level on Contactor 305-C-001
305-LIC-3017 DCS Controller, PID Action with H & L Alarm Threshold, Direct Action Controller
Wet Condensate Level on Contactor 305-C-001
305-LIC-3013 DCS Controller, Gap Control Action with H & L Alarm Threshold, Direct Action Controller
Off-Spec Gas to Flare from Contactor 305-C-001
305-PIC-3024 DCS Controller, PID Action, Direct Action Controller
Dry Spec Gas Outlet from Contactor 305-C-001
305-PIC-3009 DCS Controller, PID Action with H & L Alarm Threshold, Direct Action Controller
Vent Gas Temperature from TEG Reflux Condenser 305-E-003
305-TIC-3102 DCS Controller, PID Action with H & L Alarm Threshold, Direct Action Controller
TEG Temperature inside Reboiler 305-H-001
305-TIC-3109 DCS Controller, PID Action with H & L Alarm Threshold, Direct Action Controller
Glycol Level on Flash Drum 305-V-002
305-LIC-3210 DCS Controller, PID Action with H & L Alarm Threshold, Direct Action Controller
TEG Reflux Condenser Top Temperature Control The (TEG + water) vapour outlet from TEG Reflux Condenser (305-E-003) outlet temperature Controller (305-TIC-3102) controls the three way valve controller 305-TV-3102 which bypasses the cold fluid to the inlet of 305-E-003 to maintain the top temperature at 95C. TEG Reboiler Temperature Control The TEG Reboiler temperature is controlled by 305-TIC-3109 which controls fuel gas flow through Control Valve 305-TV-3109. The corresponding air flow is adjusted by a mechanical link from the discharge of Air Blowers 305-K-001A/B for the Reboiler Main burner. The Fuel gas flow and air flow link are preset for a fixed Air–Fuel ratio. Fuel Gas Pressure Control and Pilot Gas Pressure Control for TEG Reboiler The Fuel gas pressure for the Burner Assembly of 305-H-001 is controlled by selfregulating Pressure Controller 305-PCV-3175 which controls the fuel gas pressure at 0.5 barg. The Pilot gas is taken at downstream of Fuel Gas Pressure Control Valve 305-PCV-3175 and the Pilot Gas pressure is maintained at 0.3 barg by a self-regulating Pressure Control Valve 305-PCV-3176. Burner Air Fan Controls Fan 305-K-001-A or -B can be selected as duty fan from control room using the selector switch 305-HIS-3182. Normally 305-K-001A or B will be running and is indicated by 305-MIXI-3182/3183. If the running fans trips, then the standby fan will immediately start. The standby fan is always kept in Auto mode as indicated by 305-MHSM-3182/3183 selector switch.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 78 of 275
Glycol Flash Drum Glycol & Condensate Level Control The glycol level in the Glycol Flash Drum is controlled by Level Controller 305-LIC-3210 which controls the rich TEG flow through the Control Valve 305-LV-3210. The condensate collected in the Glycol Flash Drum level is maintained by a Level Controller 305-LIC-3206 which adjusts the Control Valve 305-LV-3206 to the closed drain system. Glycol Flash Drum Pressure Control The Glycol Flash Drum pressure is maintained at 3.8 barg by self-regulating Pressure Control Valve 305-PCV-3201 by admitting fuel gas into the Glycol Flash Drum. If the pressure reaches 4.0 barg then 305-PCV-3211 vents gas to flare. For detailed Alarms & Trips Schedule, refer Annexure-6. 4.6
TEG INCINERATOR SYSTEM
TEG Incinerator unit is designed to burn off-gases from TEG Regeneration System and Produced Water Tank. The TEG Incinerator consists of a vertical combustion chamber directly connected to the stack through a flue gas duct, where the flue gas is quenched with dilution air at ambient temperature. The diluted gas is exhausted to the self-supported stack raiser connected with the top of the base chamber. The Combustion Chamber is equipped with a special Burner and an electrically ignitable pilot. The waste gas is directly injected together with support fuel gas and combustion air in to the combustion chamber for burning. The TEG Incinerator is designed to burn gases with the following parameters: TEG Off-Gas
Flow rate
: 464 kg/h
Temperature
: 30 – 150°C
Pressure
: 0.4 barg
Produced Water Tank Off-Gas
Flow rate
: 242 kg/h
Temperature
: 8 – 45°C
Pressure
: 0.03 barg
The TEG Incinerator Main Burner has a design capacity of 7 MW/h which is 10% higher than necessary to operate the combustion chamber at 850°C (1562°F) under maximum waste gas flow rates.
The fuel gas consumption for the Main Burner will be as follows: Minimum Normal Maximum
kg/h 8.0 57.3 60.5
Nm3/h 10 72 76
The TEG Incinerator is designed to burn waste gases from the following sources:
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1 o
TEG Vent Gas KO Drum 305-V-003
o
Produced Water Tank Off-gas
Operations Page 79 of 275
TEG off-gas is introduced through the Burner Gun and Produced Water Tank Off-Gas is introduced directly in the Combustion Chamber. During the chamber pre-heating phase, the main burner is operated with support fuel gas and combustion air only. Preheating operation will be done until combustion chamber temperature reaches 750C. The operating temperature for the combustion chamber is 850°C, maintained by regulating the Fuel Gas flow rate. The TEG Incinerator is:
provided with a UV scanner for detecting flame of Pilot burner, and
provided with a redundant self-checking UV scanner for detecting flame of Main burner
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 80 of 275
4.6.1 TEG Incinerator Controls Combustion Chamber Temperature Control (Split Control) The operating temperature for the combustion chamber maintained at 850 deg C by regulating the fuel gas flow rate. 340-TIC-6027 controls the combustion chamber temperature by throttling 340-TV-6027A on the Fuel Gas line and 340-TV-6027B on the dilution air line, in split control. Normally, the combustion chamber temperature is controlled by modulating the fuel gas valve 340-TV-6027A, while the dilution air valve 340-TV-6027B remains fully closed. As the temperature rises above the set point, 340-TV-6027A tends to close to minimum position corresponding to minimum design flow rate allowed for burner operation. In case the temperature continues to rise, the dilution air FO valve 340-TV-6027B starts opening to improve cooling down of combustion chamber. It will have a ‘low oxygen’ override control through 340-AIC-6028, which measures oxygen content at the combustion chamber outlet. In case of low oxygen, 340-AIC-6028 will override 340-TIC-6027 to modulate the dilution air valve 340-TV-6027B. Combustion Air Flow Control Combustion air flow is measured by 340-FI-6031. Fuel gas, TEG off-gas and Produced water off-gas flows are measured by 340-FI-6043, 340-FI-6044 and 340-FI-6046 respectively. These flows are factored (configurable) and added in an adder block, the output of which acts as a set point to 340-FIC-6031 to control the combustion air flow. During the start-up phase, the Heater temperature is brought to 750C in steps of 50C per hour by using fuel gas. The Radiation Temperature Controller 340-TIC-6027 is a split-range Controller with two outputs. The 0–50% signal goes to the Fuel Gas Control Valve 340-TV-6027B. The 50–100% signal from 340-TIC-6027 is compared with the Oxygen Analyzer output 340-AIC-6028 in a Comparator 340-AY-6028 which adjusts the dilution air flow to the TEG Incinerator to maintain the required excess air. Note: Refer vendor operating & maintenance manual for further details. 4.7
UTILITIES
4.7.1 Plant Air System The Compressed Air package provides the necessary amount of compressed air for use as instrument air, plant air and in Nitrogen generation package. The Air requirement for GGS will be satisfied by the Air compressor Package consisting 2 X 100% Skid mounted Oil free Screw Air Compressors type complete with all necessary accessories. The standby machine shall be available for operation in the event of high air usage or in the event that an operating compressor fails. Discharge capacity of each compressor is 1182.4 Nm³/h at 45C with discharge pressure of 10.2 barg. The Air compressor consists of an Inter and After-cooler, Water Separator and Master controller to control Compressor operation. Each Compressor package includes one Aftercooler (325-E-001A/B) after the Compressor. Aftercooler is provided after Compressor package to control outlet air temperature in case of extreme weather conditions. A Plant Air receiver 325-V-001 will be provided downstream of Independent After cooler.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 81 of 275
4.7.2 Instrument Air System The Instrument air package supplies air for use as Instrument Air, Plant Air and Nitrogen Generation. 2 X 100% Dryer Package 325-X-002A/B is provided for production of Instrument air at a dew point of -35˚C at 7.5 barg. The Instrument Air Dryer package consists of a Pre-Filter, two molecular sieve bed Adsorption/Regeneration towers, after filter and a Master controller to control Dryer operations. Pressure in the downstream of Instrument air dryer package will be sized to provide at least 20 minutes backup supply to essential IA users excluding Nitrogen within the pressure range of 9.0 barg to 4.5 barg. Part of Instrument Air is used as Plant Air with necessary header pressure control for distribution to Utility hose station. Loading and unloading of the Air compressor will be triggered by monitoring the pressure controller 325-PIC-4732 on instrument air receiver.
4.7.2.1
Process Description
Each compressor package includes one after cooler (325-E-001A/B) for maintaining the discharge temperature to meet system requirements. A wet Air Receiver (325-V-001) will be provided downstream of the compressors.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 82 of 275
Wet air from the receiver is routed to Instrument Air Dryer package (325-X-002A/B) which consists of alumina bed absorption/regeneration unit for production of air at a dew point of -35˚C at 7.5 barg. The dryer beds are regenerated using dry instrument air. Each dryer package is provided with Prefilter, Dryer vessel & Afterfilter. Coalescing Air Pre-filters filter any water, dust and foreign matter from Plant Air before it is sent to the Air Dryer Beds. Downstream of the dryer beds, Afterfilters are installed to remove any desiccant fines carried over from the dryers before the air reaches the Instrument Air Receivers. The dried instrument air is then lead to distribution header through Instrument Air Receiver (325-V-002). Instrument Air (IA) Receiver (325-V-002) downstream of the drier package will be sized to provide at least 20-minutes backup supply to IA users (excluding N2 package supply) while the pressure in the receiver falls from 8.5 barg to 4.5 barg for a flow of 495 Nm3/h. Pressure Transmitter 325-PT-4737 is provided on the line going to Instrument Air Distribution Header initiates Plant ESD when instrument pressure falls below 4.41 barg (4.5 kg/cm2g). AIR COMPRESSOR Equipment Tag No. Type Fluid Description Suction Temperature Suction Pressure Discharge Temperature Discharge Pressure Flow Molecular Weight Power Absorbed at Shaft Material of Construction
325-K-001A/B Screw Ambient Air Rated Unit 45 ºC 0.943 bara 54 ºC 11.0 bara 1480.2 Nm3/h 28.99 1485 kW Casing: Cast Iron DIN 1691-64-GG20 Impeller: CS DIN 17200 CK35 – PTFE Coated
INSTRUMENT AIR RECEIVER Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Molecular Weight Material of Construction Dimensions
325-V-002 Vessel Instrument Air Maximum Minimum –15.0 82.0 12.0 — 15.0 50.0 4.5 9.5 28.82 CS 1000 OD x 3000 Length T/T
Unit ºC barg ºC barg
mm
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
4.7.2.2
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 83 of 275
Instrument Air Package Controls
Pressure Transmitter 325-PT-4732 will initiate two-level interlock based on the air pressure. When the air pressure drops below 6 barg, it will close On/Off Valve 325-XV-4665 located on the line going to Plant Air distribution header. The second level of interlock which is set at 5 barg to close On/Off Valve 325-XV-4725 located on the Instrument Air supply line to Nitrogen package. The Pressure Transmitter 325-PT-4732 will control loading and unloading of the Air compressors. Instrument Air distribution header pressure will also be provided with pressure Low-Low alarm represented by 325-PALL-4737. Refer Cause & Effect Diagram 250-EPR-CNE-05001. Wet air receiver level is also provided with level High-High trip by 325-LAHH-4653 and high level alarm is indicated by 325-LAH-4650. Refer Cause & Effect Diagram 250-EPR-CNE-05001 ESD Level-3, Unit-325) for more details. The following signals will be available from air compressors for indication in the DCS:
Running status
Shutdown alarm
Common alarm
Note: Refer vendor operating & maintenance manual for further details. 4.7.3 Nitrogen System 4.7.3.1
Process Description
Nitrogen requirement in GGS plant is essentially for blanketing of tanks and secondary gas for compressor seals. The nitrogen Generation package employs Membrane technology for generation of nitrogen from air. The nitrogen Generation Package (324-X-001) consists of one train with a capacity of 68 Nm3/h capacity of 98 vol% purity. The Nitrogen package unit consists of three sections namely:
Feed Air supply
Membrane nitrogen Generation Section
Product gas
The nitrogen unit can be started or stopped locally or remotely. The feed air is taken from Instrument Air Receiver 325-V-002. Inlet Parameters Parameters Pressure (Min./Max.) Temperature (Min./Max.) Dew point Feed Air Capacity
Unit barg C C Nm3/h
Value 7.0/10.0 15/50 –35°C @ 7.5 barg 230
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 84 of 275
Product Gas Parameters Parameters Pressure (Min./Max.) Temperature (Min./Max.) Product Capacity
Unit barg C Nm3/h
Value 5.5/7.0 15/+50 68
The Instrument air stream from Instrument Air Receiver (325-V-002) is directed to Nitrogen Generator (324-X-001) through Micron- and Activated Carbon -Filters. The Dry Feed Instrument Air (15 – 50 ºC & 7.0 – 8.2 barg) is led through a set of one-micron filter (324-F-001A) and one AC Filter (324-F-002A) to qualify feed air quality. One standby set of Micron Filter (324-F-001B) & AC Filters (324-F-002B) are provided to allow change-over for maintenance of filters. The feed air is then heated in Heater (324-H-001) to 50ºC (max). The filtered and dried feed instrument air is then fed to nitrogen Generation Package (324-X-001). The oxygen-rich waste gas is discharged to atmosphere at a safe location. The generated nitrogen stream is continuously analysed for oxygen content by Oxygen Analyzer (324-AIT-4619) provided on downstream of membrane modules. A total number of five membrane modules constitute the package wherein three operate and two are spared to take care of maintenance requirement of any two modules at a time. The package is designed to supply 68 Nm³/h of nitrogen with 98% product purity under normal operation at 5.5 barg (min) and 7 barg (normal) pressure and 45–50C temperature. If nitrogen is found to be off-specification, it is automatically vented to atmosphere at safe location. Additional requirement for flare purging (if any) is provided by back-up bottle supply system. The produced nitrogen is then routed to nitrogen Storage Receiver (324-V-001). The receiver is sized to provide 10-minutes hold-up for normal operation design flow of 68 Nm3/h. The nitrogen distribution system takes the supply through this storage receiver to cater to GGS plant nitrogen demand. Back-up supply of nitrogen will be provided by nitrogen bottles. It will supplement the nitrogen receiver whenever required.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 85 of 275
NITROGEN RECEIVER Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Molecular Weight Material of Construction Dimensions
324-V-001 Vessel Nitrogen Maximum –15.0 12.0 15.0 5.5
Minimum 82.0 — 50.0 8.2
Unit ºC barg ºC barg
28.0 SS-316 1900 OD x 4700 Length T/T
mm
324-V-001 Vessel Wet Air Maximum –15.0 12.0 15.0 8.0
Unit ºC barg ºC barg
WET AIR RECEIVER Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Molecular Weight Material of Construction Dimensions 4.7.3.2
Minimum 82.0 — 50.0 9.5
28.82 CS 1000 OD x 3000 Length T/T
mm
Nitrogen Package Controls
The package purity will be set at 98% purity for nitrogen. If the package purity for nitrogen has reached to 97% or below, On/Off Valve 324-XV-4616 will be closed from local control panel and Off-spec Vent Valve 324-XV-4620 will be opened; off- spec gas from the package will be vented until nitrogen purity has reached 98%. If it continues at nitrogen purity of 97% or below for more than 15-minutes, then the package will undergo shutdown. A common alarm will be provided for ICSS indication in case of any fault in the package. Similarly Oxygen Analyzer 324-AIT-4619 provided in the package continuously monitors oxygen percentage and High High and High alarms will be generated in ICSS system when oxygen content goes high. It is possible to stop nitrogen package from ICSS and shutdown of the package will be initiated when nitrogen goes below 97% for more than 15 minutes. Emergency shutdown of the heater is initiated when the skin temperature of the heater goes High (324-TAHH-4602). The following signals will be available for indication to ICSS:
Common alarm
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Heater running
High oxygen alarm
High differential pressure alarm
Heater outlet gas temperature high and low
Operations Page 86 of 275
It is possible to stop nitrogen system from ICSS Note: Refer vendor operating & maintenance manual for further details 4.7.4 Utility Water 4.7.4.1
Utility Water Description
Raw water used in GGS area is required for drinking water purposes and for utility water in hose stations. The source of raw water for GGS area is Bore-well. Raw water is pumped from the wells using the Bore-well Water Pump 326-P-001A/S of 23 m 3/h capacity and fed to the Utility Water Tank 326-T-002. The Utility Water tank is designed for 171 m3 capacity corresponding to 7-day hold up of utility water. The Utility water requirement for hose stations and potable water is 20 m 3/day. The bore-hole water pump is controlled based on the Utility Water Tank level by the ON-OFF Level Controller 326-LIC-4760. The water is then pumped by 326-P-003A/B which is configured in Duty/Standby mode, to the plant utility water distribution header at a controlled pressure. The pressure of the header is controlled by the Pressure Controller 826-PIC-4763 which acts on the Control Valve 326-PV-4763 in the return line. UTILITY WATER TANK Equipment Tag No. Type Process Medium Description Design Temperature Design Pressure Operating Temperature Operating Pressure Operating Capacity Density at WPT Dimension Material of Construction
326-T-002 Tank Water Maximum –15.0 3.5 4.0
Minimum 82.0 –2.5 45.0
Unit ºC mbarg ºC 1.5 mbarg 171.0 m3 997.0 kg/m3 6000 ID x 7200H mm Shell/Bottom: Carbon Steel; Internals: SS 316L
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 87 of 275
BOREHOLE WATER PUMP Equipment Tag No. Type Fluid Description Temperature Suction Pressure Discharge Pressure Flow Density of Liquid at WPT Viscosity of Liquid at WPT Power Absorbed at Shaft Material of Construction
326-P-001 Submergible Centrifugal Raw water Rated 45 0.9 14.1 23.1 995 0.764 47.74 Casing: CS ; Impeller: CS
Unit ºC bara bara m³/h kg/m³ Cp kW
UTILITY WATER PUMP Equipment Tag No. Type Fluid Description Temperature Suction Pressure Discharge Pressure Flow Density of Liquid at WPT Viscosity of Liquid at WPT Power Absorbed at Shaft Material of Construction 4.7.4.2
326-P-003A/B Centrifugal Utility Water Rated 45 0.67 7.6 11.6 995 0.765 8.24 Casing: CS; Impeller: CS
Unit ºC bara bara m³/h kg/m³ Cp kW
Utility Water System Control Description
The pressure of the utility water recirculated to Utility Water Tank 326-T-002 from utility water distribution header will be controlled by Controller 326-PIC-4763 acting on Control Valve 326-PV-4763. Utility Water Tank 326-T-002 level will be controlled by 326-LICA-4760 from DCS by means of On/Off Controller which will control START/STOP of the Bore-hole Pump 326-P-001A/S. Utility water tank level is also provided with High- High and Low- Low alarms which are indicated by 326-LAHH-4761 and 326-LALL4761. Refer Cause & Effect diagram 250-EPR-CNE-05001. Note: Refer vendor operating & maintenance manual for further details
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 88 of 275
4.7.5 Potable Water System 4.7.5.1
Potable Water Description
Potable Water is delivered by road tankers and unloaded into the Potable Water Tank 326-T-003 using a potable water tanker Unloading Pump 326-P-004. Potable water will be stored in 326-T-003 of capacity 12 m3 considering 3-day hold-up for potable water consumption. Potable water from the tank is then pumped by Potable Water Distribution Pumps 326-P-005A/B in to the Plant Distribution Header after getting treated in Potable Water Sterilisation package 326-X-005. The sterilisation package is a Chlorination Injection Facility in which the chlorine dosing (NaOCl) into potable water and is controlled based on Free Residual chlorine (FRC) in the potable water return line measured by the ORP(Oxygen Reduction Potential) Analyzer 326-AT-4605. The Potable Water Pump 326-P-005A/B, configured in Duty/Standby mode, should be started prior to the start of sterilisation package. The unit can be operated locally from the field LCP or from DCS, based on the Local/Remote selection in the LCP. As the unit is started, the pre-chlorination sampling is taken and if the chlorine level is lower than the value set by the ORP Analyzer 326AT-4605, Chlorine Dosing Pump 826-DPM-006 will start. Once chlorine level reaches the set value, dosing pump will stop. Manual Stop is possible from field as well as from DCS. The typical potable water and its parameters are given in the following table: Operating Pressure Operating Temperature Design Pressure Design Temperature Conductivity Total hardness Chloride Ions Fe Turbidity
(min/norm/max) (min/norm/max) (min/max)
2.5/5.3/5.8 (ambient)(1) 6.5 -15/82 250 Desirable 150-500 200 0.3 5
barg ºC barg ºC µS/cm mg/l CaCo3 mg/l mg/l Units
In Auto mode, when either of the potable water pump 326-P-005A or B starts (i.e. ‘RUN’ feedback is received), sterilisation unit START command is issued (326-HS-4802) to start the chlorination dosing pumps. The unit will automatically stop when both the potable water pumps are not running. Refer Appendix-A for motor control and interlock details. Potable Water Sterilisation system is a standalone packaged unit. All control and safeguarding functions will be implemented in the supplier’s local control panel. ‘Common Fault alarm’, ‘common trip’ etc. shall be generated by the package and made available to DCS. Refer supplier’s documents for complete details.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 89 of 275
POTABLE WATER TANKER UNLOADING PUMP Equipment Tag No. Type Fluid Description Temperature Suction pressure Discharge pressure Flow Density of Liquid at WPT Viscosity of Liquid at WPT Power Absorbed at Shaft Material of Construction
326-P-004 Centrifugal Pump Potable Water Rated 45 0.26 1.5 10 993 0.765 1.28 Casing: SS 316L; Impeller: SS 316L
Unit ºC bara bara m³/h kg/m³ Cp kW
POTABLE WATER DISTRIBUTION PUMP Equipment Tag No. Type Fluid Description Temperature Suction Pressure Discharge Pressure Flow Density of Liquid at WPT Viscosity of Liquid at WPT Power Absorbed at Shaft Material of Construction
4.7.5.2
326-P-005A/B Centrifugal Potable Water Rated 45 0.37 5.36 6.25 993 0.765 1.73 Casing: SS316L; Impeller: SS316L
Unit ºC bara bara m³/h kg/m³ Cp kW
Potable Water System Control Description
The pressure of the potable water recirculated to potable water tank from potable water distribution header will be controlled by 326-PIC-4789 (set point ATM) and Control Valve 326-PV-4789. The potable water is chlorinated so as to have a Free Residual Chlorine (FRC) value of 0.2-0.5 ppm at the final outlet. The Chlorination unit will start only when Potable Pump 326-P-005A or 326-P-005B is running. The following signals will be taken from sterilization package to DCS system: o
Common fault alarm
o
Running indication
In addition to the above, START and STOP shall be possible from DCS system. Potable water tank is also provided with level High-High (326-LAHH-4771) and Low Low alarms (326-LALL-4771). Refer Cause & Effect Diagram 250-EPR-CNE-05001.
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 90 of 275
Note: Refer vendor operating & maintenance manual for further details 4.7.6 Diesel System Diesel will be used in GGS as an alternative fuel for GTGs and in the Emergency Diesel Generator. It is also used in the vehicle filling stations. Diesel is used as an alternative fuel for GTG in case fuel gas is not available. The diesel fuel used for the GTG should meet the following specifications and supply conditions. Diesel Quality PARAMETER Operating Pressure (Min/Norm/Max) Operating Temperature(Min/Norm/Max) Grade Quality
UNIT barg ºC Free Water
Particulates Density at 15°C Viscosity at 15°C Lower Heating Value Pour point
kg/m3 cP kJ/kg ºC
VALUE 4.5/5.0/5.5 Ambient Automotive Grade 5 micron removed 860 35.2 42800 –10
Diesel Consumption
Diesel will be used as an alternative fuel for 2x100% GTGs and as fuel in 1x100% diesel-driven generators for emergency power generation. Consumption figures tabulated below are based on vendor values.
Diesel will be routed to filling stations where the same will be dispensed to individual diesel consuming vehicles through standard pump and dispenser systems. Consumption is 3 m3/h (50 lpm).
No facility for underground storage of diesel is envisaged in vehicle filling stations. Consumption Diesel Users GTG-A or -B Emergency Power Generation
MW 2.5 1.2
Diesel kg/h 1205 (*1) 319.4 (*2)
Required Pumping Rate m3/h 1.6 (*1) 0.4 (*2)
(*1) Heat rate 20622 kJ/kWh (Vendor data)
(*2) With 10% margin on vendor consumption figures 4.7.6.1
Description of Diesel System
Clean diesel is brought into the plant by tankers and unloaded into an atmospheric diesel storage tank (322-T-001) located in the GGS area using Diesel Tanker Offloading Pump (322-P-002). Pump capacity is 10 m3/h and tanker unloading will be done only during daytime (6 hours).
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 91 of 275
The atmospheric Diesel Storage Tank of nominal capacity 59 m3 is based as backup supply to emergency generator for 7-days. Since the GTG is dual-fired, no storage of diesel has been considered for the GTG operation. Diesel will be pumped by Diesel Transfer Pump (322-P-001A/S) to Diesel Pre-filter (322-F-001A/B - 2 filters of duplex type) for removal of any particles. Diesel Transfer Pump capacity is 5 m3/h. One pump is provided in the warehouse as standby. Then it flows through Diesel Filter Coalescer (322-F-002A/B) to bring down the water content from 1000 to 100 ppmv. The filtered diesel flows through distribution header and then to consumers in GGS. Diesel circuit will be maintained pressurized to ensure supply to GTG if gas supply fails. A spill-back line is provided from the discharge of Diesel Transfer Pumps to the Diesel Storage Tank 322-T-001. 4.7.6.2
Diesel System Control Description
When Diesel Storage Tank 322-T-001 level is High High (322-LAHH-3402), it will initiate emergency shutdown by stopping diesel tanker Unloading Pump 322-P-002. When diesel Storage Tank 322-T-001 level is Low Low (322-LALL-3402), it will stop Diesel Transfer Pump 322-P-001A. If Diesel Transfer Pump suction pressure is Low Low (322-PALL-3422), it will initiate shutdown by stopping Diesel Transfer Pump 322-P-001A, GTG and Emergency Diesel Generator. For more details, refer Cause & Effect Diagram 250 - EPR-CNE-05001.
4.8
FUEL GAS SYTEM
Fuel gas is supplied at two pressure levels in the GGS. The HP fuel gas at 25 barg (HP fuel gas pressure set for Gas turbine requirement) will be used to run Gas turbine drives. This HP fuel gas is filtered to have 99.9% removal of particles of 100-micron size. The LP fuel gas at 5 barg will be used for: o
Blanketing of various process tanks and vessels
o
Flares as pilot and purge gas
o
Stripping gas for TEG regeneration
o
Fuel Gas for TEG regeneration
o
Fuel in TEG incinerator and direct fired heater
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 92 of 275
Fuel Gas Consumption The consumption of fuel gas is based on lean gas operation in summer time and the following other parameters. Power Generators There are 2X100% power generators driven by gas turbines. Gas turbine HP fuel gas consumptions are based on vendor data for operation of one GTG HP Fuel Gas Consumption for Gas Turbines Load LCV Heat Rate Total Fuel Gas Consumed Peak Fuel Gas Demand (2 GTG Operating at 60% load 5.62 MW)
o Based on a load of 9.367 MW
MW kJ/kg kJ/kWh kg/h
9.367 41176 (35 MJ/Nm3) 11094 2460*
kg/h
3480
PETRO-CANADA EBLA PALMYRA B.V Unit : GGS
00180-PCP-300-PDMan-12503-01 GGS Operating Manual Vol #1
Operations Page 93 of 275
Typical HP fuel gas properties and composition are given in Table given below: Parameters Operating Pressure Operating Temperature Design Pressure Design Temperature Molecular weight LHV Solid Particulates COMPOSITION H2S H2O TE GLYCOL Nitrogen CO2 Methane Ethane Propane i-Butane n-Butane i-Pentane
LP – Lean Gas
LP – Rich Gas
Sum
Wint
Sum
Wint
barg
26
26
26
ºC
29.6
29.92
28.4
Unit
barg ºC kJ/kg
HP
26
Lean Sum 26
Rich Wint 26
28.69
30.25
28.82
30 30 30 30 30 30 82 82 82 8 82 82 19.27 18.94 19.45 18.89 19.1 18.92 44737 44736 48250 48360 47948 48360 99.9% of particles
View more...
Comments
