c09 oil production, stabilisation and dehydration

NIGERIA – OML 130 AKPO Field Development Project

Operating Manual Book 1

COMPANY Ref: NG50-7-756-OPE-GM-AA-00-0001-C09 Revision: 01 Status: IFR Class: 1 Date: 23/01/2007 Page: 1/98

Chap 9 Final Draft This document is the property of TOTAL and shall not be disclosed to third parties or reproduced without permission of the COMPANY.

Reserved to COMPANY This document is:

Approved Code 1

Approved with minor comments Code 2

Rejected Code 3

Reviewed with comment Code 4

Date:

ASB Final Acceptance Code 5

Date:

Remarks:

01 23/01/2007 Final Draft ODL

00 05/01/2007 First Draft ODL

REV DATE DESIGNATION INITIATOR REVIEWED BY APPROVED BY

Chapter 9

Oil Production, Stabilisation and Dehydration System





TABLE OF CONTENTS

SECTION 1 INTRODUCTION........................................................................................6

1.1 System Overview ....................................................................................................... 7 1.1.1 Purpose........................................................................................................ 7 1.1.2 Key Components .......................................................................................... 8 1.1.3 Locations...................................................................................................... 8 1.1.4 System Dependencies.................................................................................. 8

1.2 Process Description ................................................................................................. 10 1.2.1 Separator Internal Operation ...................................................................... 10 1.2.2 1st Stage Separation and Test Separation .................................................. 10 1.2.3 2nd Stage Separation .................................................................................. 13 1.2.4 Crude Oil Heating ....................................................................................... 13 1.2.5 3rd Stage Separation................................................................................... 14 1.2.6 Electrostatic Dehydrator ............................................................................. 15 1.2.7 4th Stage Separation ................................................................................... 16 1.2.8 Crude Oil Transfer Pumps and Crude Oil Cooling ...................................... 16

SECTION 2 SYSTEM/EQUIPMENT DESCRIPTION ...................................................18

2.1 1st Stage Separators 5-DS-3110A and 5-DS-3110B................................................. 19 2.2 Test Separator 5-DS-3120 ....................................................................................... 22 2.3 2nd Stage Separator 5-DS-3210 .............................................................................. 25 2.4 Crude Oil Pre-Heaters 5-EC-3310- A1/A2/B1/B2 ..................................................... 27 2.5 Crude Oil Heaters 5-EC-3320A1/2B1/2.................................................................... 30 2.6 3rd Stage Separator 5-DS-3410............................................................................... 33 2.7 3rd Stage Separator Pumps 5-GX-3410A/B ............................................................. 35 2.8 Electrostatic Dehydrator 5-DS-3510......................................................................... 37 2.9 4th Stage Separator 5-DS-3610 ............................................................................... 40 2.10 Crude Oil Transfer Pumps 5-GX-3720A/B................................................................ 42 2.11 Crude Oil Coolers 5-EC-3710A/B/C ......................................................................... 44

SECTION 3 INSTRUMENTATION, CONTROL AND SHUTDOWN ............................52

3.1 1st Stage Separators 5-DS-3110A/B........................................................................ 53 3.1.1 Pressure..................................................................................................... 53 3.1.2 Temperature............................................................................................... 54 3.1.3 Level........................................................................................................... 54 3.1.4 Flow............................................................................................................ 54 3.1.5 Safegaurding .............................................................................................. 55

3.2 Test Separator 5-DS-3120 ....................................................................................... 56 3.2.1 Pressure..................................................................................................... 56 3.2.2 Temperature............................................................................................... 57





3.2.3 Level........................................................................................................... 57 3.2.4 Flow............................................................................................................ 57 3.2.5 Safeguarding .............................................................................................. 58

3.3 2nd Stage Separator 5-DS-3210 .............................................................................. 59 3.3.1 Pressure..................................................................................................... 59 3.3.2 Temperature............................................................................................... 59 3.3.3 Level........................................................................................................... 59 3.3.4 Flow............................................................................................................ 59 3.3.5 Safeguarding .............................................................................................. 60

3.4 Crude Oil Pre-Heaters 5-EC-3310A1/A2/B1/B2........................................................ 61 3.4.1 Pressure..................................................................................................... 61 3.4.2 Temperature............................................................................................... 62 3.4.3 Safeguarding .............................................................................................. 62

3.5 Crude Oil Heaters 5-EC-3320- A1/2B1/2.................................................................. 63 3.5.1 Pressure..................................................................................................... 63 3.5.2 Temperature............................................................................................... 64 3.5.3 Flow............................................................................................................ 64 3.5.4 Safeguarding .............................................................................................. 64

3.6 3rd Stage Separator 5-DS-3410............................................................................... 66 3.6.1 Pressure..................................................................................................... 66 3.6.2 Temperature............................................................................................... 66 3.6.3 Level........................................................................................................... 66 3.6.4 Flow............................................................................................................ 67 3.6.5 Safeguarding .............................................................................................. 67

3.7 3rd Stage Separator Pumps 5-GX-3410A/B ............................................................. 68 3.7.1 Pressure..................................................................................................... 68 3.7.2 Flow............................................................................................................ 68 3.7.3 Leakage Control System ............................................................................ 68 3.7.4 Safeguarding .............................................................................................. 69

3.8 Electrostatic Dehydrator 5-DS-3510......................................................................... 70 3.8.1 Pressure..................................................................................................... 70 3.8.2 Temperature............................................................................................... 70 3.8.3 Level........................................................................................................... 71 3.8.4 Flow............................................................................................................ 71 3.8.5 Safeguarding .............................................................................................. 71

3.9 4th Stage Separator 5-DS-3610 ............................................................................... 72 3.9.1 Pressure..................................................................................................... 72 3.9.2 Temperature............................................................................................... 72 3.9.3 Level........................................................................................................... 72 3.9.4 Flow............................................................................................................ 72 3.9.5 Safeguarding .............................................................................................. 73

3.10 Crude Oil Transfer Pumps 5-GX-3720A/B................................................................ 74 3.10.1 Pressure..................................................................................................... 74 3.10.2 Flow............................................................................................................ 74 3.10.3 Leakage Control System ............................................................................ 74 3.10.4 Safeguarding .............................................................................................. 74





3.11 Crude Oil Coolers 5-EC-3710A/B/C ......................................................................... 76 3.11.1 Pressure..................................................................................................... 76 3.11.2 Temperature............................................................................................... 76 3.11.3 Flow............................................................................................................ 77 3.11.4 Safeguarding .............................................................................................. 78

3.12 System Control and Setpoints .................................................................................. 79 3.13 Alarm and Trip Settings............................................................................................ 80 3.14 Pressure Safety Valve Settings ................................................................................ 85 3.15 Valve List ................................................................................................................. 88

SECTION 4 SAFETY REQUIREMENTS......................................................................90

4.1 Health ...................................................................................................................... 91 4.1.1 Personal Protective Equipment................................................................... 91

4.2 Safety....................................................................................................................... 92 4.2.1 Chemical Hazards ...................................................................................... 92 4.2.2 Hazardous Sources .................................................................................... 92 4.2.3 Nitrogen...................................................................................................... 93

4.3 Environment............................................................................................................. 94 4.3.1 Waste Control............................................................................................. 94

SECTION 5 REFERENCE DOCUMENTS FOR SYSTEM/EQUIPMENT.....................95





Tables Table 9.1 – Design and Operating Data – 1st Stage Separator 5-DS-3110A 21 Table 9.2 – Design and Operating Data – Test Separator 5-DS-3120 24 Table 9.4 – Design and Operating Data – Crude Oil Pre-Heaters 5-EC-3310- A1/A2/B1/B2 29 Table 9.5 – Design and Operating Data – Crude Oil Heaters 5-EC-3320A1/2B1/2 32 Table 9.6 – Design and Operating Data – 3rd Stage Separator 5-DS-3410 34 Table 9.7 – Design and Operating Data – 3rd Stage Separator Pumps 5-GX-3410A/B 36 Table 9.8 – Design and Operating Data – Electrostatic Dehydrator 5-DS-3510 39 Table 9.9 – Design and Operating Data – 4th Stage Separator 5-DS-3610 41 Table 9.10 – Design and Operating Data – Crude Oil Transfer Pumps 5-GX-3720A/B 43 Table 9.11 – Design and Operating Data – Crude Oil Coolers 5-EC-3710A/B/C 45 Table 9.12 – Hazardous Sources 93 Photographs Photograph 9.1 – ICSS Display – Oil Separation, Stabilisation and Dehydration System 17 Photograph 9.2 – 1st Stage Separator 20 Photograph 9.3 – Test Separator 23 Photograph 9.4 – 2nd Stage Separator 26 Photograph 9.5 – Crude Oil Pre-Heater 28 Photograph 9.6 – Crude Oil Heater 31 Photograph 9.7 – 3rd Stage Separator 34 Photograph 9.8 – 3rd Stage Separator Pump 36 Photograph 9.9 – Electrostatic Dehydrator 38 Photograph 9.10 – 4th Stage Separator 41 Photograph 9.11 – Crude Oil Transfer Pump 42 Photograph 9.12 – Crude Oil Cooler 44 Figures Figure 9.1 – 1st Stage Separators 5-DS-3110A/B and Test Separator 5-DS-3120 46 Figure 9.2 – 2nd Stage Separator 5-DS-3210 47 Figure 9.3 – Crude Oil Pre-Heaters 5-EC-3310A/B and Crude Oil Heaters 5-EC-3320A/B 48 Figure 9.4 – 3rd Stage Separator 5-DS-3410 and 3rd Stage Separator Pumps 5-GX-3410A/B 49 Figure 9.5 – Electrostatic Dehydrator 5-DS-3510 50 Figure 9.6 – 4th Stage Separator 5-DS-3610, Transfer Pumps and Crude Oil Coolers 51





SECTION 1 INTRODUCTION

This Chapter provides an overview of the Oil Production, Stabilisation and Dehydration System, followed by a detailed description of the overall process flow, including details of system interfaces and detailed equipment descriptions. It is supported by simplified flow diagrams.





1.1 System Overview

1.1.1 Purpose

The primary purpose of the oil treatment system is to achieve the required crude oil specification in terms of RVP and BS&W.

Total design capacity is 235000BLPD of liquids production, comprising 185000stBOPD crude, 50000BWPD of produced water and 545MMscfd of associated gas. Export oil specification is 0.3% BS&W, 60mg/l salt content and less than 10psia RVP at 37.8°C.

The Oil Production, Stabilisation and Dehydration System comprises a single oil separation train providing four stages of separation, and with inter-stage heating between the 2nd and 3rd stage separation to ensure the crude oil product meets the RVP specification. An Electrostatic Dehydrator between the 3rd and 4th stage separation is provided to meet the BS&W specification.

The dehydrated crude is pumped from the 4th Stage Separator and cooled to 40°C prior to being sent to the cargo tanks of the hull through the loading manifold. The quality of stabilised oil sent to the storage tanks is monitored by an in-line BS&W Analyser located downstream of the coolers. To reduce both the crude heating and cooling loads, warm oil from the 4th Stage Separator is used to heat the incoming oil to the 3rd Stage Separator through a Crude Oil Pre-heater.

When the LP, MP or HP compression system is shutdown, the concerned separator pressure controller will reach its upper range and open the pressure control valve to flare.

The hull is provided with a 10in transfer manifold to redirect off-spec product from the hull tanks to the inlet of the crude oil heaters for reprocessing. This oil reprocessing is limited to small amount of crude to achieve the required crude oil RVP specification. Production from the wells is reduced to ensure that the design capacity of downstream equipment is not exceed.

Antifoam injection points are provided on the inlet to each 1st Stage Separator. Provision is also made on the inlet to the 2nd Stage Separator and the 3rd Stage Separator for possible antifoam injection. A demulsifier injection point is provided on the oil outlet from the 3rd Stage Separator, which is installed as a backup to the demulsifier injection points upstream of the riser-top chokes. Methanol injection points are provided on the gas outlets to the flare from the 1st Stage and Test Separators. Corrosion inhibitor injection points are provided on the oil outlet of the Electrostatic Dehydrator and the inlet to the Crude Oil Coolers.

The vessels are equipped with baffles to minimise the effect of ship motion.





1.1.2 Key Components

The Oil Production, Stabilisation and Dehydration System comprises the following major components:

• 2 x 60% 1st Stage Separators 5-DS-3110A/B

• 1 x 100% Test Separator 5-DS-3120

• 1 x 100% 2nd Stage Separator 5-DS-3210

• 2 (2 x 50%) Crude Oil Pre-Heaters 5-EC-3310A1/A2/B1/B2

• 2 x 100% Crude Oil Heaters 5-EC-3320A/B

• 1 x 100% 3rd Stage Separator 5-DS-3410

• 2 x 100% 3rd Stage Separator Pumps 5-GX-3420A/B

• 1 x 100% Electrostatic Dehydrator 5-DS-3510

• 1 x 100% 4th Stage Separator 5-DS-3610

• 2 x 100% Crude Oil Transfer Pumps 5-GX-3720A/B

• 3 x 50% Crude Oil Coolers 5-EC-3710A/B/C

1.1.3 Locations

The main components of the oil production, stabilisation and dehydration system are located in Modules S4, S5, P4 and P5

1.1.4 System Dependencies

Operation of the Oil Production, Stabilisation and Dehydration System dependent on, or interfaces with, the following:

• ICSS (Chapter 01)

• Firewater System (Chapter 02)

• Oil Production Wells, Flowlines and Controls (Chapter 03)

• Production / Test Manifolds and Pigging Facilities (Chapter 08)

• Produced Water Treatment (Chapter 10)

• LP, MP and HP Gas Compression (Chapter 11)

• HP / LP Flares and Hull Vent Systems (Chapter 14)





• Cargo Storage Tanks and Facilities (Chapter 18)

• Cooling Water (Chapter 24)

• Hot Water (Chapter 25)

• HP and LP Fuel Gas (Chapter 26)

• Service and Instrument Air System (Chapter 27)

• Nitrogen Generation System (Chapter 28)

• Chemical Injection System (Chapter 29)

• Methanol System (Topsides, Hull and Sub-sea) (Chapter 30)

• Power Generation, Emergency and Essential Generators (Chapter 31)

• Open Drains (Hull and Topsides) (Chapter 35)

• Closed Drains (Chapter 36)





1.2 Process Description

1.2.1 Separator Internal Operation

Note: The 1st Stage, Test and 2nd Stage Separators provide 3-phase separation of oil, water and gas. The 3rd Stage Separator, although designed for 3-phase separation, is normally used for 2-phase separation of oil and gas, so the produced water line is normally no flow. The 4th Stage Separator provides 2-phase separation of oil and gas.

During 3-phase separation, oil and water mixed with gas are carried into the separators. The liquid/gas mixture degasses as it passes through the inlet diffuser and baffles inside the vessels, and the gas travels above the liquid vessel. The liquid flows along the vessels with sufficient residence time to allow the oil and water separate. The oil flows over a weir and through the oil outlet compartment, and water is removed from the water compartment under level control. Saturated gas leaves the vessel through a demister where entrained liquid is coalesced into large droplets, which are collected on the oil side of the weir.

During 2-phase separation, oil and gas are separated. The oil/gas mixture degasses as it passes through the inlet diffuser and baffles inside the vessels, and the gas travels above the oil vessel. The gas leaves the vessel through a wire mesh demister and gas box where entrained liquid is coalesced into large droplets.

1.2.2 1st Stage Separation and Test Separation

Refer to Process Flow Diagram: NG50-5-500-PRO-PF-AB-00-0011 – Oil Production and Stabilisation (Sheet 1 of 2)

1.2.2.1 1st Stage Separation

Normal operating mode of the 3-phase 1st Stage Separators 5-DS-3110A and 5-DS-3110B is with both separators operating in parallel at 79barg, providing 3-phase separation. Two 60% 1st Stage Separators operating in parallel are required due to the limitation of the physical size of having one 100% sized vessel.

Note: The 60% sizing of the 1st Stage Separators is to cater for potential flow imbalances due to slugging. To allow for flow imbalances, the normal steady-state operation is with a 50/50 flow split between the two vessels and the 60% is not taken into account.

Two Production Manifolds are provided, one for each 1st Stage Separator. Simultaneous production via both manifolds from the same production branch is prohibited. One branch is allowed to flow to only one of the Production or Test Manifolds at a time through mechanically interlocked valves. The 1st Stage Separators can also receive condensate return from the Gas Injection Suction Scrubber, although there is normally no flow.

The liquid hydrocarbon from the two parallel 1st Stage Separators is combined into a single stream for further processing at the 2nd Stage Separator. Flash gas from the 1st Stage Separators is routed to the export compression system via the single Glycol Dehydrator and excess gas is routed to flare. Water from the separators is routed through an Oily Water Drum 5-DS-4110 to the Produced Water Treatment Package 5-UA-4130 for further processing.





Antifoam injection points are provided on the inlet to each separator and methanol injection points are provided on the gas outlet from the separators to flare.

To produce the high water-cut wells in mid and late field life, the operating pressure of one of the 1st Stage Separators may need to operate in a LP mode. The nominated 1st Stage Separator operating pressure will be reduced to 2nd Stage Separator operating pressure of 22.5barg. With one of the 1st Stage Separator operating in LP mode the oil from the vessel is routed to the Crude Oil Pre-heaters 5-EC-3110A/B.

A simplified diagram is shown in Figure 9.1 – 1st Stage Separators 5-DS-3110A/B and Test Separator 5-DS-3120

The 1st Stage Separators have been sized to cope with the following operating conditions:

• Case 1A: HP Mode 79barg at 50°C Vapor 2897m³/h Oil 820m³/h Water 167m³/h

• Case 1B: HP Mode 79barg at 78°C Vapor 3555m³/h Oil 787m³/h Water 166m³/h

• Case 1C: Future LP mode 22.5barg Vapor 158000m³/h Oil 304m³/h Water 497m³/h

A 20% margin has been included in all flows due to unbalance between trains A and B and possible slugging effects These separators are designed to receive 30m³ liquid slug volume between normal liquid level and high liquid level alarm.

The overflow weir is an adjustable type to optimise and adjust interface liquid level in the future.

1.2.2.2 Test Separation

The operating pressure of the Test Separator is 79barg in the HP Mode or 22.5barg in the LP Mode with reduced throughput. Later in field life, when water cut is high, the Test Separator will operate in the LP Mode. However, the LP operating mode can be performed for well testing and well start-up purposes at any time, therefore, the vessel is designed to be capable of the LP mode of operation from day one. To allow the separator to operate in the HP and LP modes, a selector switch, enables the set point of the pressure controller and the change over of remotely operated valves to redirect the oil flow. The modes of operation are explained below:

HP Mode (Normal Operation):

The Test Separator operating in parallel and at the same pressure, 79barg, as the two 1st Stage Separators.





Individual well through flowlines can be tested on a regular basis through the Test Separator, via the test manifold. Only one flowline can be connected to the topsides test manifold at a time via mechanically interlocked valves.

The liquid hydrocarbon production from the test separator is combined with the liquid hydrocarbon stream from the 1st Stage Separators for further processing in the 2nd Stage Separator. Flash gas from the Test Separator is routed to the export compression system via the Glycol Dehydrator Inlet Cooler. Excessive gas is routed to the HP Flare. Produced water from the separator is routed to produced water treatment system.

LP Mode:

Test Separator operating at 22.5barg with reduced throughput.

To facilitate the LP operation, the Test Separator is provided with additional piping to the HP Compressor and to the Crude Oil Pre-heaters with interlocked valves for isolation.

An antifoam injection point is provided on the test separator inlet and a methanol injection point on the gas outlet to flare.

The Test Separator is designed for the maximum flowrate of 424m³/h (45000blpd) and has been sized to cope with the following operating conditions:

• Case 1: 45 KBOPD no water cut, HP mode 79barg at 60°C Vapour 2980m³/h Oil 424m³/h Water 0m³/h

• Case 2: 45 KBOPD, high water cut, LP mode 22.5barg at 80°C Vapor 5576m³/h Oil 131m³/h Water 186m³/h

• Case 3: Year 8, minimum temperature, HP mode 79barg at 33°C Vapor 257m³/h Oil 32m³/h Water 0m³/h

• Case 4: Year 7, loop P40. Max temperature, LP mode 22.5barg at 102°C Vapor 373m³/h Oil 11.6m³/h Water 191m³/h

A 10% margin has been included in all flows.

The separator is designed to receive a 30m³ liquid slug between normal and high liquid alarm levels.





A simplified diagram is shown in Figure 9.1 – 1st Stage Separators 5-DS-3110A/B and Test Separator 5-DS-3120

1.2.3 2nd Stage Separation


The 2nd Stage Separator 5-DS-3210 is a 3-phase separator operating at a pressure of 22.5barg.

The 2nd Stage Separator receives the combined hydrocarbon liquid flow from the two 1st Stage Separators and when operating from the Test Separator. The separator also receives condensate returns from:

• Gas Dehydrator Inlet Scrubber 5-DS-5520

• Gas Export Compressor Suction Scrubbers Train A and Train B, 5-DS-5410A/B

• HP Fuel Gas Scrubber 5-DS-2210

The liquid hydrocarbon from the 2nd Stage Separator is routed to the 3rd Stage Separator via the Crude Oil Pre-heaters 5-EC-3310A/B and Crude Oil Heaters 5-EC-3320A/B. Flash gas from the separator is routed to the HP Gas Compressor Suction Coolers and any excess gas is routed to flare. Produced water from the separator is routed to produced water treatment system.

A simplified diagram of the 2nd Stage Separation is shown in Figure 9.2 – 2nd Stage Separator 5-DS-3210.

The 2nd Stage Separator has been sized to cope with the following operating conditions:

• Case 1A: 22.5barg at 45°C Vapor 3493m³/h Oil 1434m³/h Water 87m³/h

• Case 1B: 22.5barg at 72°C Vapor 3406m³/h Oil 1424m³/h Water 82m³/h

A 10% margin has been included in all flows.

1.2.4 Crude Oil Heating


To assist achieving the RVP specification and aid water separation, the Crude Oil Pre-Heaters 5-EC-3310A1/2B1/2 and the Crude Oil Heaters 5-EC-3320A1/2B1/2 heat the crude to a





temperature of 90°C. Crude oil from the 2nd Stage Separator, mixed with condensate returns is routed to the Crude Oil Pre-heaters from:

• LP Compressor Scrubber Pumps 5-GX-5130A/B

• MP Compressor Scrubber Pumps 5-GX-5230A/B

• HP Compressor Suction Scrubbers 5-DS-5320A/B

When operating in the low pressure mode, crude oil may also be routed from a 1st Stage Separator or the Test Separator. The combined flow passes through the tube side of the pre-heaters and heat is exchanged with oil from the Crude Oil Transfer Pumps in the shell side of the pre-heaters, which also reduces the temperature of the crude going to storage through the crude oil coolers.

After pre-heating the oil passes through the tube side of the Crude Oil Heaters where the crude is further heated by the hot water system. Varying the flow of hot water through the shell side of the heaters controls the temperature of the crude. The heated crude is then routed to the 3rd Stage Separator. Off-spec product from the cargo tank pumps can be routed through a normally closed block valve to the inlet side of the Crude Oil Heaters for further reprocessing. Skimmed oil from the produced water treatment system is pumped by the Skimmed Oil Return Pumps 5-GX-4130A/B to the inlet side of the Crude Oil Heaters.

A simplified diagram is shown in Figure 9.3 – Crude Oil Pre-Heaters 5-EC-3310A/B and Crude Oil Heaters 5-EC-3320A/B

1.2.5 3rd Stage Separation


The 3rd Stage Separator 5-DS-3410 provides 2-phase separation operating at a pressure of 8barg. The separator operates as a 2-phase separator, but it is designed as a 3-phase separator to allow operational flexibility, therefore the produced water line is normally no flow. The separator receives the crude oil flow from the crude oil heaters and the condensate returns from:

• LP fuel gas scrubber

• Closed drain drum pumps

• HP flare drum pumps

• LP flare drum pumps

• 3rd Stage Separator Pumps minimum flow return





The 3rd Stage Separator has been sized to cope with the following operating conditions:

• Case 1A: 8barg at 90°C Vapor 7130m³/h Oil 1471m³/h Water 79m³/h

• Case 1B: 8barg at 90°C Vapor 4892m³/h Oil 1442m³/h Water 73m³/h

A 10% margin has been added on all the above flows.

Flash gas from the separator is routed to the MP gas compression suction coolers and excess gas is routed to flare. Produced water from the separator is routed to produced water system.

The 3rd Stage Separator Pumps 5-GX-3410A/B pump oil from the separator and start-up/make-up water from water injection system to the Electrostatic Dehydrator. The discharge pressure of these pumps is 12.5barg to compensate the pressure drop of mixing valve/line upstream of Electrostatic Dehydrator and ensures 1.5bar above vapour pressure of fluid to the 3rd Stage Separator to avoid any vaporisation in the Electrostatic Dehydrator.

A simplified diagram of the 3rd Stage Separation and Pumps is shown in Figure 9.4 – 3rd Stage Separator 5-DS-3410 and 3rd Stage Separator Pumps 5-GX-3410A/B.

1.2.6 Electrostatic Dehydrator


The Electrostatic Dehydrator 5-DS-3510 is provided to achieve the required crude specification of 0.3% BS&W. The Electrostatic Dehydrator is located downstream the 3rd Stage Separator, and fed by the 3rd Stage Separator Pumps 5-GX-3410A/B.

The minimum BS&W at the inlet of the electrostatic dehydrator must be equal to, or over 5%. When the BS&W is lower than 5%, additional treated seawater from the water injection system is added upstream of the 3rd Stage Separator Pumps.

As the water and oil mixture enters the vessel below the electrodes it is immediately subjected to an electrical field. The electrical field is set up between a lower hot electrode and a grounded electrode located at the interface. This field is strong enough to coalesce and separate the water droplets. The unit is equipped with two electrical power units. The electrical field can be increased from 12kV to 18kV in case one of the two transformers is out of service. With one of the units out of service and the other operating at the higher voltage it may be necessary to trim back production to keep within the 0.3% BS&W specification.

On/Off control of the unit is from the PCS, a local control panel is provided for indication.





From the dehydrator outlet the crude is the routed to the 4th Stage Separator and water to the Oily Water Drum 5-DS-4110.

A 16” bypass line is provided around the Dehydrator.

The Electrostatic Dehydrator has been sized to cope with the following operating conditions:

Oil 1471m³/h Water 78m³/h Water salinity 35.7g/l Produced water salinity 10g/l

A 10% margin has been added on all flows.

A simplified diagram of the Electrostatic Dehydrator is shown in Figure 9.5 – Electrostatic Dehydrator 5-DS-3510

1.2.7 4th Stage Separation


The 4th Stage Separator 5-DS-3610 provides 2-phase separation and operates at 1barg.

The separator receives dehydrated warm crude oil from the Electrostatic Dehydrator and flow from the crude oil transfer pumps minimum flow line. The dehydrated warm crude oil from the separator is routed to the Crude Oil Transfer Pumps 5-GX-3720A/B. Gas from the separator is routed to the LP Gas Compressor Suction Cooler 5-EC-5110 and excess gas is routed to the LP Flare.

The 4th Stage Separator has been sized to cope with the following operating conditions:

• Case 1A: 2barg at 79°C Vapor 20281m³/h Oil 1310m³/h

• Case 1B 2barg at 79°C) Vapor 19617m³/h Oil 1307m³/h

A 10% margin has been added on all flows.

A simplified diagram of the 4th Stage Separation is shown in Figure 9.6 – 4th Stage Separator 5-DS-3610, Transfer Pumps and Crude Oil Coolers

1.2.8 Crude Oil Transfer Pumps and Crude Oil Cooling






The 2 x 100% Crude Oil Transfer Pumps 5-GX-3720A/B operate at 4barg output. The pumps are used to pump the dehydrated warm crude oil through the Crude Oil Pre-heaters 5-EC-3310A1/2 and 5-EC-3310B1/2, through the Crude Oil Coolers 5-EC-3710A/B/C, to the crude oil storage tanks via the loading manifold. The discharge pressure of the pumps compensates the pressure drop of lines and heat exchangers. The standby pump automatically starts on loss of the duty pump. The pumps are operated locally or remotely from the PCS.

The 3 x 50% plate type Crude Oil Coolers 5-EC-3710A/B/C reduce the crude oil temperature to 40°C. Passing the crude through the hot side of the heaters and cold water through the cold side cools the crude oil prior to storage. Temperature control is achieved by modulating the throughput of cold water through the coolers.

Normal operation is two coolers operating one on standby. If both Crude Oil Pre-Heaters 5-EC-3310A/B are being bypassed then three coolers are required. The operator in the field carries out valve line up for the various operating configurations manually.

A simplified diagram of the Transfer Pumps and Coolers is shown in Figure 9.6 – 4th Stage Separator 5-DS-3610, Transfer Pumps and Crude Oil Coolers

The following photograph shows the ICSS Screen Display for the Oil Separation, Stabilisation and Dehydration System

Photograph 9.1 – ICSS Display – Oil Separation, Stabilisation and Dehydration System

To be inserted.





SECTION 2 SYSTEM/EQUIPMENT DESCRIPTION

The Oil Production, Stabilisation and Dehydration System comprises the following major equipment:

• 1st Stage Separator 5-DS-3110A

• 1st Stage Separator 5-DS-3110B

• Test Separator 5-DS-3120

• 2nd Stage Separator 5-DS-3210

• Crude Oil Pre-Heaters 5-EC-3310A1/A2/B1/B2

• Crude Oil Heaters 5-EC-3320- A1/2B1/2

• 3rd Stage Separator 5-DS-3410

• 3rd Stage Separator Pumps 5-GX-3410A/B

• Electrostatic Dehydrator 5-DS-3510

• 4th Stage Separator 5-DS-3610

• Crude Oil Transfer Pumps 5-GX-3720A/B

• Crude Oil Coolers 5-EC-3710A/B/C





2.1 1st Stage Separators 5-DS-3110A and 5-DS-3110B

Refer to: P&ID NG50-5-500-PRO-PI-AB-31-0001 – 1st Stage Separator Train A

The 1st Stage Separator 5-DS-3110A is located in Module S4 Upper Deck EL 50000 and 5-DS-3110B is located in Module P4 Upper Deck EL 50000

NOTE: 1st Stage Separators 5-DS-3110A and 5-DS-3110B are identical in construction and service. This paragraph describes 5-DS-3110A. For Tagging differences, refer to P&ID NG50-5-500-PRO-PI-AB-31-0002 – 1st Stage Separator Train B

Constructed of carbon steel the 1st Stage Separator is 15.8m long with an internal diameter of 4.4m, supplied by CMP Arles with Aker Kvaerner internals. The 3-phase separator is sized to obtain a nominal residence time of 5 minutes for both crude and water.

The vessel is fitted with a single, top inlet vane type distributor and cascade tray. This design consists of a number of vanes contained in a boxed housing, which reduce the inertia of the incoming fluid and considerably reduces the formation of mist particles. The vanes direct the flow onto an inclined cascade tray, which assists with degassing the liquid and introduces it into the bulk liquid phase. Downstream from the inlet diffuser is a double perforated distribution plate, designed to reduce turbulence and allow controlled flow of liquid into the separation region.

Surge plates and perforated baffles positioned in the separating section of the vessel give optimum flow distribution and provide efficient fluid damping. Over the weirs is a single perforated distribution plate to provide resistance to bulk liquid movements and thus provide some wave motion damping in the separator. The weir elevation is +2000mm and a change of weir elevation can be achieved by adding bolted plates on the existing weir plate.

Vortex breakers are fitted at both the water and the oil outlets. The Aker Kvaerner Systems vortex breakers are flush profile with cover plate type designed for use in FPSOs.

A vertical demister mat extractor extends from the top of the vessel to the bottom of a gas box. The stainless steel knitted wire mesh has a density of 200kg/m³ and is placed to fill the upper part of the vessel. The gas moves through the mat and liquid impinges on the wire mesh and coalesces into large droplets. The droplets fall to the liquid collecting arrangement in the bottom of the gas box and are evacuated by means of a drainpipe.

All the vessel internal components are accessible through 24” manholes.

The vessel is provided with a 4” vent valve a 3” sand jetting water valve and two 2” utility valves. Six 4” locked closed drain valves connect to the closed drains collection system. Drip pans connect to the hazardous open drains collection system. Sample points are provided on the on the gas outlet, the HP flare line and the water outlet line. Corrosion prevention and monitoring is installed on the 12 “water outlet line.

Shutdown valves are provided on the crude oil inlet and outlet lines, the HP gas lines and the produced water line. An Emergency Blow Down Valve (EBDV) is provided to the HP flare warm temperature collection system together with a manually operated 2” bypass line. To allow for vessel isolation, spectacle blinds are fitted on the gas, the crude oil and the produced water outlets and to the closed drain collection system. A spool spacer piece is fitted to the crude inlet line.





The 1st Stage Separators are protected with passive fire protection for an extended blowdown time to 30 minutes and are fitted with sacrificial anodes for cathodic protection.

Pressure Safety Valves (PSV) provide protection for the blocked outlet case and relieve to the HP Flare. Each of the 3 x 50% PSVs is provided with a double block and bleed arrangement and a downstream block valve. All the two duty PSVs block valves are locked open. The spare PSVs, inlet block valves are locked closed with the downstream block valve locked open. For further details refer to Table 3.14 - Pressure Safety Valve Settings

The following photograph shows a 1st Stage Separator in its installed location:

Photograph 9.2 – 1st Stage Separator

Design and operating parameters are set out in Table 9.1 Design and Operating Data –1st Stage Separator 5-DS-3110A.

To be inserted.





Table 9.1 – Design and Operating Data – 1st Stage Separator 5-DS-3110A

Parameter Design Operating

HP Mode Pressure Full Vacuum to 93barg 79barg

HP Mode Temperature -20 to 93°C 50 to 78°C

LP Mode Pressure 35barg 22.5barg

LP Mode Temperature -20 to 117°C 33 to 105°C

Liquid Carry Over in Gas 13.4l/MMSm³

Maximum Oil in Water 1000ppm

Maximum Water in Oil (BS&W) 5%

Sand Jetting System:

Water Flow (per hole) 15l/minute

Overall Flowrate 172.8m³/hr

Pressure Drop 4bar

Inlet Water Velocity 10m/s





2.2 Test Separator 5-DS-3120

Refer to: P&ID NG50-5-500-PRO-PI-AB-31-0003 – Test Separator

Location: Module P4 Upper Deck EL 50000

The test separator is constructed of carbon steel and measures 13m long with an internal diameter of 3.8m, supplied by CMP Arles with Aker Kvaerner internals. The 3-phase separator is sized to obtain a nominal residence time of 5 minutes for both crude and water.


Surge plates and perforated baffles positioned in the separating section of the vessel give optimum flow distribution and provide efficient fluid damping. Over the weirs is a single perforated distribution plate to provide resistance to bulk liquid movements and thus provide some wave motion damping in the separator. The weir elevation is +2000mm and a change of weir elevation can be achieved by adding bolted plates on the existing weir plate.




The vessel is provided with a 3” vent valve a 3” sand jetting water valve and two 2” utility valves. Four 4” locked closed drain valves connect to the closed drains collection system. Spectacle blinds and spool pieces allow for isolation of the vessel. Drip pans connect to the hazardous open drains collection system. Sample points are provided on the gas outlet, HP flare line and the water outlet line. Corrosion prevention and monitoring is installed on the 8 “water outlet line.

Shutdown valves are provided on the crude oil inlet and outlet lines, the HP gas lines and the produced water line. An emergency blow down valve is provided to the HP flare warm temperature collection system. The EBDV is provided with a 2” bypass line with manually operated valves.

To allow for vessel isolation, spectacle blinds are fitted on the gas, the crude oil and the produced water outlets and to the closed drain collection system. A spool spacer piece is fitted to the crude inlet line.

The Test Separator is protected with passive fire protection for an extended blowdown time to 30 minutes and is fitted with sacrificial anodes for cathodic protection.





Pressure safety valves provide protection for the vessel for the blocked outlet case and relieve to the HP flare. Each PSV is provided with an inlet double block and bleed arrangement and a downstream block valve. The duty PSVs block valves are locked open. The spare PSVs, inlet block valves are locked closed with the downstream block valve locked open. For further details refer to Table 3.14 - Pressure Safety Valve Settings

The LP mode gas line from the Test Separator to the HP Compressor is equipped with PSVs. These PSVs are sized for a blocked outlet and relieve to HP warm temperature flare collection system. A locked open and locked closed block valve arrangement allows for on-line maintenance of the PSVs. The LP mode crude oil line to the Crude Oil Pre-Heaters is equipped with a PSV sized for control valve failure and also relieves to HP warm temperature flare collection system.

For further details refer to Table 3.14 - Pressure Safety Valve Settings

The following photograph shows the Test Separator in its installed location:

Photograph 9.3 – Test Separator

Design and operating parameters are set out in Table 9.2 Design and Operating Data – Test Separator 5-DS-3120

To be inserted.





Table 9.2 – Design and Operating Data – Test Separator 5-DS-3120


HP Mode Pressure Full Vacuum to 93barg 79barg

HP Mode Temperature -20 to 93°C 50 to 78°C

LP Mode Pressure 35barg 22.5barg

LP Mode Temperature -20 to 117°C 33 to 105°C




Sand Jetting System:

Water Flow (per hole) 15l/minute

Overall Flowrate 126m³/hr

Pressure Drop 4bar

Inlet Water Velocity 7m/s





2.3 2nd Stage Separator 5-DS-3210

Refer to: P&ID NG50-5-500-PRO-PI-AB-32-0001 – 2nd Stage Separator


The 2nd Stage Separator is constructed of carbon steel and measures 17m long with an internal diameter of 4.6m. The 3-phase separator is sized to obtain a nominal residence time of 5 minutes for both crude and water.


Surge plates and perforated baffles positioned in the separating section of the vessel give optimum flow distribution and provide efficient fluid damping. Over the weirs is a single perforated distribution plate to provide resistance to bulk liquid movements and thus provide some wave motion damping in the separator.




The vessel is provided with a 4” vent valve and two 2” utility valves. Six 4” locked closed drain valves connect to the closed drains collection system. Spectacle blinds and spool pieces allow for isolation of the vessel. Drip pans connect to the hazardous open drains collection system. Sample points are provided on the gas outlet, HP flare line and the water outlet line.

Shutdown valves are provided on the crude outlet line, the HP gas lines and the produced water line. An emergency blow down valve is provided to the HP flare warm temperature collection system. The EBDV is provided with a 2” bypass line with manually operated valves. To allow for vessel isolation, spectacle blinds are fitted on the gas, the crude oil and the produced water outlets and to the closed drain collection system. A spool spacer piece is fitted to the crude inlet line.

The 2nd Stage Separator is insulated for personnel protection and fitted with sacrificial anodes for cathodic protection.

Pressure safety valves provide protection for the blocked outlet case and relieve to the HP flare. Each of the 2 x 100% PSVs is provided with a block and bleed valve upstream of the PSV and a downstream block valve. The duty PSVs block valves are locked open. The spare PSVs, upstream block valve is locked closed with the downstream block valve locked open. For further details refer to Table 3.14 - Pressure Safety Valve Settings





The following photograph shows the 2nd Stage Test Separator in its installed location:

Photograph 9.4 – 2nd Stage Separator

Design and operating parameters are set out in Table 9.3 Design and Operating Data – 2nd Stage Separator 5-DS-3210

Table 9.3 – Design and Operating Data – 2nd Stage Separator 5-DS-3210


Pressure Full Vacuum to 28barg 22.5barg

Temperature -10 to 90°C 73°C




To be inserted.





2.4 Crude Oil Pre-Heaters 5-EC-3310- A1/A2/B1/B2

Refer to: P&ID NG50-5-500-PRO-PI-AB-33-0001 – Crude Oil Pre-Heaters

Location: Module P5 Main Deck EL 37000

Due to the mechanical limit and constraint 2 x 50% shells are provided for each 100% crude oil pre-heater as follows:

• 5-EC-3310A:

5-EC-3310A1 and 5-EC-3310A 2

• 5-EC-3310B:

5-EC-3310B1 and 5-EC-3310B2

NOTE: Crude Oil Pre-Heaters 5-EC-3310A and 5-EC-3310B are identical in construction and service. This paragraph describes Crude Oil Pre-Heater 5-EC-3310A. For Tagging differences, refer to P&ID NG50-5-500-PRO-PI-AB-33-0001 – Crude Oil Pre-Heaters

Supplied by Delaunay et Fils, the horizontally mounted crude oil pre-heater shells are constructed of carbon steel and the tubes from stainless steel 316L. The shells are provided with heat conservation insulation.

Crude oil with flashed gas and water is pre-heated through the tube side of the heat exchanger. Stabilised crude oil from the 4th Stage Separator is used as the heating medium through the shell side.

Each unit is provided with a 2” valve for cleaning operations. Locked closed drain valves connect to the closed drains collection system. Drip pans connect to the hazardous open drains collection system. A locked closed valve and a 2” drain valve allow draining to the drip pan. The two pre-heaters are provided with manual valves on the inlet and outlet of both sides of each unit to allow individual units to be bypassed. Check valves are fitted on both sides of each pre-heaters outlet. Spectacle blinds and spool pieces allow for isolation of the units. A 20” line fitted with Hand Valve HV-33101 provides a bypass line around the Crude Oil Pre-Heaters direct to the Crude Oil Heaters Crude Oil Heaters 5-EC-3320A1/2B1/2.

Pressure safety valves protect the units from tube rupture and for the fire case on the outlet lines to the Crude Oil Heaters. The safety valves protecting against tube rupture are provided with a block and bleed valve upstream of the PSV and a downstream block valve. The duty PSVs block valves are locked open. The spare PSVs, upstream block valve is locked closed with the downstream block valve locked open. The fire safety case PSV is provided with a block and bleed valve upstream of the PSV and a downstream block valve. A spare fire safety case PSV is stored in the workshop. The PSVs relieve to the HP flare. For further details refer to Table 3.14 - Pressure Safety Valve Settings.

The following photograph shows the Crude Oil Pre-Heater in its installed location:





Photograph 9.5 – Crude Oil Pre-Heater

Design and operating parameters are set out in Table 9.4 Design and Operating Data – Crude Oil Pre-Heaters 5-EC-3310- A1/A2/B1/B2

To be inserted.





Table 9.4 – Design and Operating Data – Crude Oil Pre-Heaters 5-EC-3310- A1/A2/B1/B2


Pressure:

Shell 14barg 3.7barg

Tube 32barg 10.3barg

Temperature:

Shell -5 to 105°C 79.4°C

Tube -5 to 105°C 56°C

General:

Shell Side Tube Side

Maximum Pressure Drop

1bar 1bar

Fluids Stabilised Crude Oil Crude Oil + Gas + Produced Water

Total Flowrate per (each unit)

483791kg/h

604627kg/h

Number of Passes 1 2

Material Carbon Steel Stainless Steel 316L

Heat Exchanged 5500kW

Area (each unit) 985m²

Note: For Turndown Case with only one of the two 1st Stage Separator operating, 50% of total production, refer to 3.4.1 Crude Oil Pre-Heaters 5-EC-3310- A1/2B1/2.





2.5 Crude Oil Heaters 5-EC-3320A1/2B1/2

Refer to: P&ID NG50-5-500-PRO-PI-AB-33-0002 – Crude Oil Heaters

Location: Module P5 Main Deck EL 37000

Due to the mechanical limit and constraint 2 x 50% shells are provided for each 100% crude oil heater as follows:

• 5-EC-3320A:

5-EC-3320A1 and 5-EC-3320A 2

• 5-EC-3320B:

5-EC-3320B1 and 5-EC-3320B2

NOTE: The Crude Oil Heaters 5-EC-3320A1/2 and 5-EC-3320B1/2 are identical in construction and service. This paragraph describes Crude Oil Heater 5-EC-3320A1/2. For Tagging differences, refer to P&ID NG50-5-500-PRO-PI-AB-33-0002 – Crude Oil Heaters

Supplied by Bronswerk Heat Transfer, the horizontally mounted crude oil heater shells are constructed of carbon steel and the tubes from stainless steel 316L. The shells are provided with heat conservation insulation.

Crude oil with entrained gas and water is heated through the tube side of the heat exchanger. Hot water is used as the heating medium through the shell side. The common 12” hot water inlet and outlet lines are provided with shutdown valves.

Each unit is provided with a 2in valve for cleaning operations. Locked closed drain valves connect to the closed drains collection system. A 2” drain valve allows draining to the drip pan that also connects to the hazardous open, drains collection system.

The two heaters are provided with manual valves on the inlet and outlet of both sides of each unit to allow individual units to be bypassed. Check valves are fitted on both sides of each pre-heaters outlet. Spectacle blinds and spool pieces allow for isolation of the units.

Pressure safety valves protect the units from tube rupture and for the fire case on the outlet lines to the Crude Oil Heaters. The PSV protecting against tube rupture is provided with a locked open downstream block valve. The fire safety sized PSV is provided with a block and bleed valve upstream of the PSV and a downstream block valve. Spare PSVs are stored in the workshop. The 10” off-spec product line from the hull reprocessing to the Crude Oil Heaters is provided with pressure safety valves sized for check valve backflow. The PSVs relieve to the HP flare, for further details refer to Table 3.14 - Pressure Safety Valve Settings

The following photograph shows the Crude Oil Pre-Heater in its installed location:





Photograph 9.6 – Crude Oil Heater

Design and operating parameters are set out in Table 9.5 Design and Operating Data – Crude Oil Heaters 5-EC-3320A1/2B1/2

To be inserted.





Table 9.5 – Design and Operating Data – Crude Oil Heaters 5-EC-3320A1/2B1/2


Pressure:

Shell 19.4barg 11.7barg

Tube 32barg 9.3barg

Temperature:

Shell 170°C 158°C

Tube 170°C 90°C

General:

Shell Side Tube Side

Maximum Pressure Drop

0.5bar 1bar

Fluids Hot Water Crude Oil + Gas + Produced Water

Total Flowrate per (each unit)

433128kg/h

1209254kg/h

Number of Passes 1 2

Material Carbon Steel Stainless Steel 316L

Heat Exchanged 32846kW

Area (each unit) 1479m²

Note: For Turndown Case with only one of the two 1st Stage Separator operating, 50% of total production, refer to 3.5.1 Crude Oil Heaters 5-EC-3320- A1/2B1/2





2.6 3rd Stage Separator 5-DS-3410

Refer to: P&ID NG50-5-500-PRO-PI-AB-34-0001 – 3rd Stage Separator


Supplied by CMP Arles with Aker Kvaerner internals the 3rd Stage Separator is constructed of carbon steel and measures 17.1m long with an internal diameter of 4.7m. The separator is sized to obtain a nominal residence time of 5 minutes for both crude and water. The separator operates as a 2-phase separator, but it is designed as a 3-phase separator to allow operational flexibility, therefore produced water line is normally no flow.






The vessel is provided with a 4” vent valve and two 2” utility valves. Six 4” locked closed drain valves connect to the closed drains collection system via a common 4” line fitted with a spectacle blind, a check and a block valve. A sample point is provided on the gas outlet to the HP flare.

Shutdown valves are provided on the crude outlet line to the 3rd Stage Separator Pumps, the MP gas outlet line and the produced water line. An emergency blow down valve is provided to the HP flare warm temperature collection system. The EBDV is provided with a 2” bypass line with manually operated valves. To allow for vessel isolation, spectacle blinds are also fitted on the gas, the crude oil and the produced water outlets. A spool spacer piece is fitted to the crude inlet line.

The 3rd Stage Separator is insulated for heat conservation and fitted with sacrificial anodes for cathodic protection.

Pressure safety valves that relieve to HP flare provide protection for a blocked outlet. Each PSV is provided with an inlet block and vent valve and a downstream block valve. The two duty PSVs block valves are locked open. The spare PSVs, upstream block valve is locked closed with the inlet block valve locked open. For further details refer to Table 3.14 - Pressure Safety Valve Settings





The following photograph shows the 3rd Stage Separator in its installed location:

Photograph 9.7 – 3rd Stage Separator

Design and operating parameters are set out in Table 9.6 Design and Operating Data – 3rd Stage Separator 5-DS-3410

Table 9.6 – Design and Operating Data – 3rd Stage Separator 5-DS-3410


Pressure Full Vacuum to 12barg 8barg





To be inserted.





2.7 3rd Stage Separator Pumps 5-GX-3410A/B

Refer to: P&ID NG50-5-500-PRO-PI-AB-34-0001 – 3rd Stage Separator

NOTE: 3rd Stage Separator Pumps 5-GX-3410A/B are identical in construction and service. This paragraph describes the 3rd Stage Separator Pump 5-GX-3410A. For Tagging differences, refer to P&ID NG50-5-500-PRO-PI-AB-34-0001 – 3rd Stage Separator

The 3rd Stage Separator Pumps are located in Module P5 Main Deck EL. 37000mm

Manufactured by Flowserve the 2 x 100% pumps are model type 12LPN17 horizontal single stage centrifugal pumps. The single volute casing is made from A 216 GR WCB and split axially. The impeller is A 487 CA 6NM and the shaft is A 434 GR BC.

Each pump is driven at 1488rpm by a TEFC 3-phase, squirrel cage induction motor 5-GA 3410A/B respectively. The Metastream pump couplings are type TSJE-0420. Electrical supply to the 250kW motors is 400V 3-phase at 50Hz.

The pumps are selected duty/standby and start/stop at the local motor control centre or via the PCS. In case of manual change over of the pumps, to maintain pressure in the electrostatic Dehydrator 5-DS-3510, the standby pump must be manually started before the duty pump is shutdown.

The pump suction and discharge valves are car seal locked open. The pumps crude oil discharge line is also provided with check valve and a ¾” utility connection. A shutdown valve is located on the pumps common 16” crude oil discharge line to the Electrostatic Dehydrator 5-DS-3510.

The pump seal cooling is provided by the cooling water system. A fluid leakage control system incorporates two collection tanks with level control instrumentation and ¾” lines, fitted with a ¾” gate valve, to dispose of the small fraction of gas to the LP Flare.

To protect the pumps, a minimum flow control is provided on the pump discharge to allow recycling of crude oil back to the 3rd Stage Separator inlet when flow decreases below 743m3/h. Each recycle line is fitted with a check valve, an 8” flow valve, two ¾” drain valves, a spectacle blind and a car seal open valve. Two 1” locked closed pump suction and discharge drain valves connect to the closed drain system via a spectacle blind, a check valve and a block valve. The pump drip pan connects to the hazardous open drains. Spectacle blinds and spool pieces are provided for isolating the pump.

The following photograph shows a 3rd Stage Separator Pump in its installed location:





Photograph 9.8 – 3rd Stage Separator Pump

Design and operating parameters are set out in Table 9.7 Design and Operating Data – 3rd Stage Separator Pumps 5-GX-3410A/B

Table 9.7 – Design and Operating Data – 3rd Stage Separator Pumps 5-GX-3410A/B


Pressure 17.4barg 12.5barg


Suction Flowrate 1734m3/hr 1576m3/hr

Differential Pressure (at rated flow) 3.5bar

Head 49.40m

Shaft Power 212kW

Pump Speed 1460rpm

Total Cooling Water Flowrate 0.6³h (10l/m)

Cooling Water Inlet Pressure/ Temperature

7barg at 28°C

Cooling Water Outlet Pressure/ Temperature

6barg at 38°C

Gas Leakage to Flare (each tank) 20g/hr

To be inserted.





2.8 Electrostatic Dehydrator 5-DS-3510

Refer to: P&ID NG50-5-500-PRO-PI-AB-35-0001 – Electrostatic Dehydrator

Location: Module S5 Upper Deck EL 50000

The, 100kVA electrostatic dehydrator comprises the following equipment:

• Electrostatic Dehydrator Vessel 5-DS-3510

• 2 x 100% High Voltage Power Units 5-DS-3510-PU1 and 5-DS-3510-PU2

• Electrostatic Dehydrator Local Panel 5-LP-3510

Electrostatic Dehydrator Vessel

Supplied by CMP Arles with Aker Kvaerner internals, the vessel is made of carbon steel and insulated for heat conservation. The vessel measures17m long with an internal diameter of 3.6m is provided with the following internal equipment:

• 16” feed distributor

• 16” oil collector

• Water collector with vortex breakers

• Interface draw off header

• Anti-motion baffles

• Three level grid assemblies

• Hanger insulators

There are two energised grids of electrodes and a third grid at the interface level to ensure a proper voltage gradient. The electrode grids are horizontal and located in parallel and separated 200mm. The interface oil/water liquid level is below the interface grid to avoid short-circuit problems.

The vessel internal components are carbon steel with P102 coating and removable through 24” manholes.

The vessel is provided with a 3” vent valve and two 2” utility valves. Six 4” locked closed drain valves connect to the closed drains collection system. Drip pans connect to the hazardous open drains collection system. Shutdown valves are provided on the crude outlet line to the 4th Stage Separator, the water line outlet line to the Oily Water Drum and on the water make-up line. The Electrostatic Dehydrator is provided with five sample points located at 5 different levels and dedicated sampling points on the oil outlet line and the oily water outlet. Corrosion prevention and monitoring is installed on the 6“ water outlet line. To allow for vessel isolation, spectacle blinds and spool spacer piece are provided. A 16” bypass line is provided with check valve and a normally closed manual block valve.





The vessel is fitted with sacrificial anodes for cathodic protection.

A pressure safety valve provides protection for the fire case and relieves to the HP flare. The PSV is provided with a locked open block valve and a vent valve. A spare PSV is stored in the workshop. A 2” bypass line with manual valves is provided around the PSV. For further details refer to Table 3.14 - Pressure Safety Valve Settings

The following photograph shows the Electrostatic Dehydrator in its installed location:

Photograph 9.9 – Electrostatic Dehydrator

High Voltage Power Units

The 2 x 100% Electrostatic Dehydrator Power Units 5-DS-3510-PU1 and 5-DS-3510-PU2 are manufactured by AKPSF/AGECELEC. They are sealed type oil immersed units, located on the top of the electrostatic dehydrator. The power unit comprises a carbon steel shell with copper windings and paper winding insulation. The magnetic circuit material is orientated grain iron and the cooling liquid is mineral oil IEC296.

Pressure bushing protects the high voltage power unit and the vessel cable entrance from ingress of crude oil and water. A buffer zone is established by the bushings being enclosed in an oil-filled housing.

To be inserted.





Electrostatic Dehydrator Local Panel

The dehydrator is normally controlled from the PCS, the Local Panel 5-LP-3510 is provided for indication. The 600x400x200mm Type AD 531204 stainless steel panel, manufactured by AKPSF/IDRM, is provided the following equipment:

• 2 x Voltmeters

• 2 x Ammeters

• 1 x Emergency trip button

• 2 x Current transducers 4-20mA

• 2 x Voltage transducers 4-20mA

• 1 x 6W 230V Space heater

Design and operating parameters are set out in Table 9.8 Design and Operating Data – Electrostatic Dehydrator 5-DS-3510

Table 9.8 – Design and Operating Data – Electrostatic Dehydrator 5-DS-3510


Electrostatic Dehydrator Vessel:

Pressure Full Vacuum to17barg 9.5barg


Power Units:

Rated Power 100kVA

Number of Phases 2

Frequency 50Hz

Primary Voltage 400V

Voltage Transformer 500/100V

Current Transformer 300/1A

Transformer Oil Volume 430litres

Control Panel:

Consumption (Maximum) 0.22kV at 50Hz





2.9 4th Stage Separator 5-DS-3610

Refer to: P&ID NG50-5-500-PRO-PI-AB-36-0001 – 4th Stage Separator

Location: Module S5 Upper Deck EL 50000

The 4th Stage Separator 5-DS-3610S is supplied by CMP Arles with Aker Kvaerner internals. The vessel is constructed of carbon steel and measures 14.2m long with an internal diameter of 4.2m. The 2-phase separator is sized to obtain a nominal residence time of 3 minutes for crude flow.



A vortex breaker is fitted at the oil outlet. The Aker Kvaerner Systems vortex breaker is a flush type profile with cover plate designed for use in FPSOs.



The vessel is provided with a 4” vent valve and two 2” utility valves. Five 4” locked closed drain valves connect to the closed drains collection system. A 2” drain valve allows draining to the drip pans that connects to the hazardous open drains collection system.

Shutdown valves are provided on the crude outlet line to the crude oil transfer pumps and the LP gas outlet line. A fail closed pressure control valve is provided to the LP flare collection system. To allow for vessel isolation, spectacle blinds are fitted on the gas, the crude oil and the produced water outlets and to the closed drain collection system. A spool spacer piece is fitted to the crude inlet line.

The 4th Stage Separator is insulated for heat conservation and fitted with sacrificial anodes for cathodic protection.

Pressure safety valves that relieve to LP flare provide protection and sized for the blocked outlet case. Each PSV is provided with an inlet block and vent valve and a downstream block valve. The two duty PSVs block valves are locked open. The spare PSVs, upstream block valve is locked closed with the inlet block valve locked open. A 2” manually operated bypass line is provided around the PSVs. For further details refer to Table 3.14 - Pressure Safety Valve Settings





The following photograph shows the 4th Stage Separator in its installed location:

Photograph 9.10 – 4th Stage Separator

Design and operating parameters are set out in Table 9.9 Design and Operating Data – 4th Stage Separator 5-DS-3610

Table 9.9 – Design and Operating Data – 4th Stage Separator 5-DS-3610


Pressure Full Vacuum to 7barg 1barg

Temperature -10 to 105°C 79.6°C


To be inserted.





2.10 Crude Oil Transfer Pumps 5-GX-3720A/B


NOTE: Crude Oil Transfer Pumps 5-GX-3720A/B are identical in construction and service. This paragraph describes the Crude Oil Transfer Pump 5-GX-3720A. For Tagging differences, refer to P&ID NG50-5-500-PRO-PI-AB-34-0001 – Crude Oil Transfer Pumps

Location: Module S5 Main Deck EL 37000.

Manufactured by Flowserve the pumps are model type 14LPN32 horizontal single stage centrifugal pumps. The casing is made from A 216 GR WCB and split axially. The impeller is A 487 CA 6NM and the shaft is A 434 GR BC. Each pump is driven at 740rpm by an ABB model M3GP355SMA8 132kW motor 5-GA 3720A. The Metastream pump coupling is type TSKS-0740. Electrical supply to the motor is 400V 3-phase at 50Hz. The pump seal cooling is provided by the cooling water system. A fluid leakage control system incorporates two collection tanks with level control instrumentation and ¾” lines, fitted with a ¾” gate valve, to dispose of the small fraction of gas to the LP Flare.

The following photograph shows a Crude Oil Transfer Pump in its installed location:

Photograph 9.11 – Crude Oil Transfer Pump

The pumps are selected duty/standby and start/stop at the local motor control centre or via the PCS.

The pump suction and discharge valves are car seal locked open. The pumps crude oil discharge line is also provided with check valve and a ¾” utility connection

To be inserted.





To protect the pumps, a minimum flow control is provided on the pump discharge to allow recycling of crude oil back to the 4th Stage Separator inlet. Each recycle line is fitted with a check valve, a 10” flow valve, two ¾” drain valves, a spectacle blind and a car seal open valve. Two 1” locked closed pump suction and discharge drain valves connect to the closed drain system via a spectacle blind, a check valve and a block valve. The pump drip pan connects to the hazardous open drains. Spectacle blinds and spool pieces are provided for isolating the pump.

Design and operating parameters are set out in Table 9.10 Design and Operating Data – Crude Oil Transfer Pumps 5-GX-3720A/B

Table 9.10 – Design and Operating Data – Crude Oil Transfer Pumps 5-GX-3720A/B


Pressure 14barg 4barg


Suction Flowrate 1440m3/hr 1309m3/hr

Differential Pressure - 2bar

Head 26.8m

Shaft Power 99kW

Pump Speed 740rpm

Cooling Water Flowrate (each pump) 0.36m³h (6l/m)

Cooling Water Inlet Pressure/ Temperature

7barg at 28°C

Cooling Water Outlet Pressure/ Temperature

6barg at 38°C

Gas Leakage to Flare (each tank) 20g/hr





2.11 Crude Oil Coolers 5-EC-3710A/B/C

Refer to: P&ID NG50-5-500-PRO-PI-AB-37-0001 – Crude Oil Coolers

NOTE: Crude Oil Coolers 5-EC-3710A/B/C are identical in construction and service. This paragraph describes the Crude Oil Coolers 5-EC-3710A. For Tagging differences, refer to P&ID NG50-5-500-PRO-PI-AB-37-0001 – Crude Oil Coolers

Manufactured by API Schmidt-Bretten GmbH & Co the 3 x 50% crude oil coolers are located in Module S5. The plate type coolers are 2.3m long with 192 plates constructed in stainless steel 316L. Stabilised crude oil is cooled through the hot side of the heat exchanger. Cold water from the cooling water distribution system is used as the cooling medium through the cold side.

Exchanger isolation in both sides is by manual type isolation valves, ball type for the stabilised oil side and butterfly type for the cooling water side. Each exchanger is provided with a 2in valve for cleaning operations. Locked closed drain valves connect to the closed drains collection system. Drip pans connect to the hazardous open drains collection system. Temperature safety valves protect the units from thermal expansion; refer to Table 3.14 - Safety Valve Settings

The following photograph shows a Crude Oil Cooler in its installed location:

Photograph 9.12 – Crude Oil Cooler

Design and operating parameters are set out in Table 9.11 Design and Operating Data – Crude Oil Coolers 5-EC-3710A/B/C

To be inserted.





Table 9.11 – Design and Operating Data – Crude Oil Coolers 5-EC-3710A/B/C


Pressure: Inlet Outlet

Cooling Medium 15barg 7barg 6barg

Crude Oil 14barg 2.6barg 1.6barg

Temperature:

Cooling Medium 105°C 28°C 39°C

Crude Oil 105°C 60.3°C 40°C

Pressure Drop:

Cooling Medium 0.39bar

Crude Oil 0.71bar

Total all Coolers Flowrate:

Cooling Medium 625m3/hr (436kg/h)

Crude Oil 727m3/hr (484kg/h)

Number of Plates 192

Surface Area 210.9m²

Duty (One Cooler) 9310kW





Figure 9.1 – 1st Stage Separators 5-DS-3110A/B and Test Separator 5-DS-3120





Figure 9.2 – 2nd Stage Separator 5-DS-3210





Figure 9.3 – Crude Oil Pre-Heaters 5-EC-3310A/B and Crude Oil Heaters 5-EC-3320A/B





Figure 9.4 – 3rd Stage Separator 5-DS-3410 and 3rd Stage Separator Pumps 5-GX-3410A/B





Figure 9.5 – Electrostatic Dehydrator 5-DS-3510





Figure 9.6 – 4th Stage Separator 5-DS-3610, Transfer Pumps and Crude Oil Coolers





SECTION 3 INSTRUMENTATION, CONTROL AND SHUTDOWN

This section provides a detailed description of the principal control functions for the Oil Production, Stabilisation and Dehydration System and how the various sub-systems are operated:

• 1st Stage Separators 5-DS-3110A/B

• Test Separator 5-DS-3120

• 2nd Stage Separator 5-DS-3210

• Crude Oil Pre-Heaters 5-EC-3310A1/A2/B1/B2

• Crude Oil Heaters 5-EC-3320A1/2B1/2

• 3rd Stage Separator 5-DS-3410

• 3rd Stage Separator Pumps 5-GX-3410A/B

• Electrostatic Dehydrator 5-DS-3510

• 4th Stage Separator 5-DS-3610

• Crude Oil Transfer Pumps 5-GX-3720A/B

• Crude Oil Coolers 5-EC-3710A/B/C

System and equipment control, alarm and trip setpoints are presented in tabular form.

For Details of the following safety and control systems refer to Chapter 01 ICSS:

• Emergency Shutdown System

• Fire & Gas System

• Process Safety System

• Ultimate Safety System

• Overall Control of Wells and Risers (OCWR)

• High Integrity Pressure Protection System (HIPPS)





3.1 1st Stage Separators 5-DS-3110A/B

Refer to: P&ID NG50-5-500-PRO-PI-AB-31-0001 – 1st Stage Separator Train A

NOTE: The 1st Stage Separators 5-DS-3110A/B are identical in construction and service. This paragraph mainly details 5-DS-3110A. For Tagging differences, refer to P&ID NG50-5-500-PRO-PI-AB-31-0002 – 1st Stage Separator Train B

The capacity of each 1st Stage Separator is around 60% of the oil and gas maximum production and 50% of the design water production. Each separator outlet is fitted with a flow meter to indicate to the Operator the real operating capacity and consequently the remaining capacity available. The consequence of too high a flowrate through a 1st Stage Separator is water carry-over to the 2nd Stage Separator. Several safeguards have been provided to avoid exceeding of separator capacity as level and pressure trips and alarms.

The OCWR does not directly control the volume put into each separator (or the test separator). Rates of production requirements can be entered in OCWR to ramp the system up subsea. Overloading a flowline could lead to the overload of a manifold/separator, which constitutes an unsafe situation. Loading of individual branches is monitored and adjusted manually.

3.1.1 Pressure

Pressure control in the 1st Stage Separator is carried out by means of two Pressure Indicator Controllers PIC-31112A and PIC-31111A.

Gas is routed preferably to Gas Dehydration with any excess gas routed to the HP Flare. Normal Pressure Indicator Controller PIC-31112A maintains a pressure of 79barg in the separator by fixing the set point of Flow Indicator Controller FIC-31113A, which acts on gas outlet to dehydration Flow Valve FV-31113A. If pressure continues to increase, high Pressure Indicator Controller PIC-31111A, which receives set point value from Flow Indicator Controller FIC-31113A, acts on control valve PV-31111A to send the excess gas to the HP flare.

If pressure increases suddenly, for example high gas flow in separator due to a slug, such that the gas flowrate sent to FV-31113A is higher than design flowrate of dehydration unit, or if FV-31113 is fully open, FIC-31113A overrides input from PIC-31112A and decreases PIC-31111A set point in order to open PV-31111A to send excess gas to flare. When PT-31111A detects a decrease to normal pressure, PIC-31112A override is removed by FIC-31113A, and then PIC-31111A switched back to normal control with PV-31111A closed. Slugs are detected by quick changes of pressure at the production manifold or riser head and in 1st Stage Separators levels and pressures. Flow Indicator Controllers FIC-31113A/B at the gas outlet exchange signals with the Overall Control of Well and Riser (OCWR) and Level Indicator Controllers LIC-31105A/B send a signal to OCWR. As the two 1st Stage Separators operate in parallel with the Test Separator, each FIC-31113A/B and FIC-31213A/B are monitored and totalised and this signal is sent to OCWR. This information is useful to manage the slug arrival in separators

To avoid transmission of slug/s downstream of the 1st Stage Separators, Flow Indicator Controllers FIC-31118A/B acts as the set point of Level Indicator Controllers LIC-31105A/B set point, if high liquid level is reached, then the flow controller set points are automatically increased.

A local Pressure Gauge 31109A indicates the separator pressure.





3.1.2 Temperature

The 1st Stage Separator Temperature Transmitter TT-31103A and Temperature Indicator TI-31103A provide temperature monitoring, high and low temperature alarms and provides temperature correction to Flow Quantity Indicator FQI-31113A.

Local Temperature Gauge TG-31104A indicates the gas temperature in the separator.

3.1.3 Level

Oil Level

Level Indicator Controller LIC-31105A controls oil level in the separator at the oil outlet by modulating fail closed Level Valve LV-31105A. For manual control the level valve is equipped with a hand wheel with a local Level Indicator LI-31105A visible from the hand wheel.

To smooth any liquid surge impact in case of slug arrival, and avoid transmission of slug/s downstream of the 1st Stage Separator, Flow Indicator Controller FIC-31118A acts as the set point for Level Indicator Controller LIC-31105A, if high liquid level is reached, then the flow controller set point is automatically increased.

Local Level Gauge LG-31102A indicates the oil level in the separator oil compartment.

Produced Water Level

Interface Level Differential Indicator Controller LDIC-31106A controls water level in the separator by modulating Level Differential Valve LDV-31106A. The LDV is equipped with a 10”bypass line for manual control if the LDV is offline.

A local Level Differential Gauge LDG-31107A indicates the oil/water interface level in the separator.

3.1.4 Flow

Gas flowrate from separator is controlled by Flow Indicator Controller FIC-31113A modulating Flow Valve FV-31113A in the outlet to gas dehydration. A Flow Element Unit FEU-31113A, a Flow Transmitter FT-31113A and a Flow Quantity Indicator FQI-31113A monitor this flow. The FQI flow data is corrected by separator pressure and temperature information signalled by Pressure Transmitter PT-31112A and Temperature Transmitter TT-31103A.

Crude oil flow from the separator is controlled by LV-31105A. A Flow Element Meter FEM-31118A and a Flow Transmitter FT-31118A monitor this flow.

Flow Transmitter FT-31119A, a Flow Element Unit FEU-31119A and a Flow Totaliser Indicator FQI-31119A monitor and totalise the water flowrate from the 1st Stage Separator to the Oily Water Drum 5-DS-4110.





3.1.5 Safegaurding

Refer to NG50-5-500-PRO-PS-AB-0000-0060 - Emergency Shutdown Diagrams

A 20” Shutdown Valve SDV-31114A is provided at the inlet to the separator. To ensure pressure balance across SDV-31114A during start-up, a 2” Shutdown Valve SDV-31116A is provided to equalise the pressure. The 2” valve is opened remotely by manual selection from control room. When the valve opens the differential pressure across SDV-31114A reduces gradually, monitored by Differential Pressure Transmitter PDT-31115A, at the required differential pressure the 20” SDV-31114A automatically opens to feed the separator. The 2” pressure equalising valve closes automatically with a time delay once the system is stabilised.

An Emergency Blowdown Valve EBDV-31123A is provided to the HP warm flare header collection system.

A 6” Shutdown Valve SDV-31121A, together with its 2” pressure equalising Shutdown Valve SDV-31101A and Pressure Differential Transmitter PDT-31101A, are located on the gas start up line to the gas dehydration inlet coolers.

A 16” Shutdown Valve SDV-31122A, together with its 2” pressure equalising Shutdown Valve SDV-31102A and Pressure Differential Transmitter PDT-31102A, are located on the gas outlet line to the HP fuel gas scrubber.

An 18” Shutdown Valve SDV-31117A is located on the crude outlet line to the 2nd Stage Separator.

A 12” Shutdown Valve SDV-31120A is located on the produced water outlet line to the oily water drum.

The 1st Stage Separator 5-DS-3110A is equipped with 3 x 50% Pressure Safety Valves PSV1-31124A, PSV2-31124A and PSV3-31124A. 1st Stage Separator 5-DS-3110B is equipped with 3 x 50% Pressure Safety Valves PSV1-31124B, PSV2-31124B and PSV3-31124B. The pressure safety valves are sized for blocked outlet and relieve to the HP warm flare collection system. A locked open and locked closed block valve arrangement allows for on-line maintenance of the PSVs. The valve settings are detailed in Paragraph 3.14 Pressure Safety Valve Settings.

For details of the emergency shutdown/s associated with the 1st Stage Separators 5-DS-3110A/B refer to NG50-5-500-PRO-PS-AB-0000-0060, Emergency Shutdown Diagrams.





3.2 Test Separator 5-DS-3120

Refer to: P&ID NG50-5-500-PRO-PI-AB-31-0003 – Test Separator

The OCWR helps the operator not to exceed the design capacity of 45000blpd. Slugs are detected by quick changes of pressure at the production manifold or riser head and in 1st Stage Separators levels and pressures. Flow Indicator Controller FIC-31213 at the gas outlet exchange signals with the OCWR and Level Indicator Controller LIC-31205 send a signal to OCWR. As the Test Separator operates in parallel with two 1st Stage Separators, The Test Separator FIC-31213 and the 1st Stage Separators FIC-31113A/B and FIC-31213A/B are monitored and totalised and this signal is sent to OCWR. This information is useful to manage the slug arrival in separators.

To avoid transmission of slug/s downstream of the Test Separator, Flow Indicator Controller FIC-31218 acts as the set point of Level Indicator Controller LIC-31205 set point, if high liquid level is reached, then the flow controller set point is automatically increased.

The separator level, pressure and oil and gas flowrate signal are sent to OCWR. The OCWR does not directly control the volume put into the test separator.

3.2.1 Pressure

Control of pressure of the fluid and liquid (slug) on arrival at the test manifold is achieved via the OCWR system.

Test separator pressure control is carried out by means of two controllers:

• Pressure Indicator Controller PIC-31212 maintains a pressure of 79barg in the separator and fixes the set point of Flow Indicator Controller FIC-31213 that acts on gas outlet to dehydration Flow Valve FV-31213.

• If pressure continues to increase, high Pressure Indicator Controller PIC-31211, which receives set point value by Flow Indicator Controller FIC-31213, act on control valve PV-31211 to send the excess gas to the HP flare warm temperature collection. There is an exchange of signals between the OCWR and Flow Indicator Controller FIC-31213. In case of slug detection the set point of Pressure Valve PV-31211, Flow Valve FV-31213 and Level Valve LV-31205 change accordingly. (HOLD CPY to confirm)

The Test Separator can operate in a HP and LP mode; flow into the separator must be stopped when performing a change of modes. To enable the separator to operate in the HP and LP modes a common selector Switch HZ-31201 enables the set point of PIC31212 and the change over of remotely operated valves as follows:

Operating Mode HP Mode LP Mode

ROV1-31201 ROV2-31201 OPEN

ROV3-31201 ROV4-31201

ROV2-31201 ROV1-31201 CLOSED

ROV4-31201 ROV3-31201





Pressure Gauge 31205 indicates the separator pressure.

3.2.2 Temperature

Temperature Transmitter TT-31203 and Temperature Indicator TI-31203 provide temperature monitoring and indication. They also provide temperature correction to the gas flow for Flow Quantity Indicator FQI-31213.

Local Temperature Gauge TG-31204 indicates the temperature in the separator.

3.2.3 Level

Oil Level

Level Indicator Controller LIC-31205 controls oil level in the separator at the oil outlet by modulating Level Valve LV-31205.

To smooth any liquid surge impact in case of slug arrival, and avoid transmission of slug/s downstream of the separator, Flow Indicator Controller FIC-31218 acts on Level Indicator Controller LIC-31205 set point, if high liquid level is reached, then the flow controller set point is automatically increased.

Local Level Gauge LG-31202 indicates the oil level in the separator oil compartment.


Interface Level Differential Indicator Controller LDIC-31206 controls water level in the separator my modulating Level Differential Valve LDV-31206.

Level Differential Gauge LDG-31207 indicates the water oil level in the separator.

3.2.4 Flow

Gas flowrate from separator is controlled by Flow Indicator Controller FIC-31213 modulating Flow Valve FV-31213 in the outlet to gas dehydration. A Flow Element Unit FEU-31213, a Flow Transmitter FT-31213 and a Flow Quantity Indicator FQI-31213 monitor this flow. The FQI flow data is corrected by separator pressure and temperature information signalled by Pressure Transmitter PT-31212 and Temperature Transmitter TT-31203.

Crude oil flow from the separator is controlled by LV-31205. A Flow Element Meter FEM-31218 and a Flow Transmitter FT-31218 monitor the crude oil flow from the separator to the Oily Water Drum 5-DS-4110.

Flow Transmitter FT-31219, a Flow Element Unit FEU-31219 and a Flow Totaliser Indicator FQI-31219 monitor and totalise the water flowrate from the 1st Stage Separator to the Oily Water Drum 5-DS-4110.





3.2.5 Safeguarding


A 16” Shutdown Valve SDV-31214 is provided at the inlet to the separator. To ensure pressure balance across SDV-31214 during start-up, a 2” Shutdown Valve SDV-31216 is provided to equalise the pressure across the 16” SDV-31214.

A 14” Emergency Blowdown Valve EBDV-31223 is provided to the HP warm flare header collection system.

A 14” Shutdown Valve SDV-31221, together with its 2” pressure equalising Shutdown Valve SDV-31201 and Pressure Differential Transmitter PDT-31201, are located on the gas outlet line to the gas dehydration inlet coolers.

A 14” Shutdown Valve SDV-31217 is located on the crude outlet line to the 2nd Stage Separator.

An 8” Shutdown Valve SDV-31220 is located on the produced water outlet line to the oily water drum.

The Test Separator 5-DS-3120 is equipped with 2 x 100% Pressure Safety Valves PSV1-31224 and PSV2-31224 sized for blocked outlet and relieve to HP warm temperature flare collection system. A locked open and locked closed block valve arrangement allows for on-line maintenance of the PSVs.

The LP mode gas line from the Test Separator to the HP Compressor is equipped with 2 x 50% Pressure Safety Valves PSV1-31205 and PSV2-31205. These PSVs are sized for a blocked outlet and relieve to HP warm temperature flare collection system. A locked open and locked closed block valve arrangement allows for on-line maintenance of the PSVs. The LP mode crude oil line to the Crude Oil Pre-Heaters is equipped with a Pressure Safety Valve PSV-31207 sized for control valve failure and also relieves to HP warm temperature flare collection system.

The PSV settings are detailed in Paragraph 3.14 Pressure Safety Valve Settings.

For details of the emergency shutdown/s associated with the Test Separator 5-DS-3120 refer to NG50-5-500-PRO-PS-AB-0000-0060, Emergency Shutdown Diagrams.





3.3 2nd Stage Separator 5-DS-3210

Refer to: P&ID NG50-5-500-PRO-PI-AB-32-0001 – 2nd Stage Separator

3.3.1 Pressure

Pressure at 2nd Stage Separator is controlled and monitored by Pressure Indicator Controller PIC-32111 in split range to control:

• Pressure Valve PV1-32111 - gas to HP warm flare temperature collection system if pressure increase above the set point.

• Pressure Valve PV2-32111 - gas to HP compressor suction coolers and maintains separator pressure at 22.5barg

3.3.2 Temperature

The separator Temperature Transmitter TT-32103 and Temperature Indicator TI-32103 provide temperature monitoring; high and low temperature alarms and provides temperature correction to Flow Quantity Indicator FQI-32113.

3.3.3 Level

Oil Level

Level Indicator Controller LIC-32105 controls oil level in the separator at the oil outlet by modulating 2 x 100% Level Valves LV1-32105 and LV2-32105. The duty level control valve is selected via switch LZ-32105.

Local Level Gauge LG2-32102 indicates the oil level in the separator oil compartment.


Interface Level Differential Indicator Controller LDIC-32106 controls water level in the separator by modulating Level Differential Valve LDV-32106.

Level Differential Gauge LDG-32107 indicates the water/oil interface level in the separator.

3.3.4 Flow

Gas flow from the separator is monitored a Flow Element FEX-32113, a Flow Transmitter FT-32113 and a Flow Quantity Indicator FQI-32113. The FQI flow data is corrected by separator temperature information signalled by Pressure Transmitter PT-32111.

Crude oil flowrate from the separator is determined by the position of the two Level Valves LV1-32105 and LV2-32105.

Flow Transmitter FT-32119, a Flow Meter FEX-32119 and Flow Totaliser Indicator FQI-32119 monitor and indicate the water flowrate from the 2nd Stage Separator to the Oily Water Drum 5-DS-4110.





3.3.5 Safeguarding


A 6” Emergency Blowdown Valve EBDV-32123 is provided to the HP warm flare header collection system.

A 12” Shutdown Valve SDV-32121, together with its 2” start-up bypass Shutdown Valve SDV-32102 and Pressure Differential Transmitter PDT-32102 are located on the gas outlet line to the HP compressor suction coolers.

A 24” Shutdown Valve SDV-32117 is located on the crude outlet line.

A 6” Shutdown Valve SDV-32120 is located on the produced water outlet line to the oily water drum.

The 2nd Stage Separator 5-DS-3210 is equipped with 2 x 100% Pressure Safety Valves PSV1-32124, PSV2-32124. The PSVs are sized for blocked outlet and relieve to HP warm temperature flare collection system. A locked open and locked closed block valve arrangement allows for on-line maintenance of the PSVs. The PSV settings are detailed in Paragraph 3.14 Pressure Safety Valve Settings.

For details of the emergency shutdown/s associated with the 2nd Stage Separator 5-DS-3210 refer to NG50-5-500-PRO-PS-AB-0000-0060, Emergency Shutdown Diagrams.





3.4 Crude Oil Pre-Heaters 5-EC-3310A1/A2/B1/B2

Refer to: P&ID NG50-5-500-PRO-PI-AB-33-0001 – Crude Oil Pre-Heaters

NOTES: The Crude Oil Pre-Heaters 5-EC-3310A1/A2/B1/B2 are identical in construction and service. This paragraph mainly details 5-EC-3310A1/A2. For Tagging differences, refer to P&ID.

A 20” bypass line is provided with Hand Valve HV-33101 to manually bypass the Pr-heaters. With the bypass line open, the two Crude Oil Heaters 5-EC-3320A/B and the three Crude Oil Coolers 5-EC-3710A/B/C need to be in operation to compensate the loss of duty given by the Pre-Heaters.

Manual valves allow bypass of individual units.

For the turndown case with only one of the two 1st Stage Separators 5-DS-3110A or 5-DS-3110B operating at 50% of total production:

Shell Side Tube Side Inlet Outlet Inlet Outlet Total Flow 241908kg/hr (for one unit) 293583kg/hr (for one unit)

Oil 241908kg/hr 241908kg/hr 269118kg/hr 267738kg/hr

Water 18820kg/hr 18730kg/hr

Vapour 5645kg/hr 7715kg/hr

Operating Pressure 3.7barg 4.7barg 10barg 9barg

Operating Temperature 79.8°C 71.5°C 68°C 73.7°C

3.4.1 Pressure

Pressure Differential Indicator PDT-33110 monitors the pressure drop through the Crude Oil Pre-Heaters 5-EC-3310A/B shell side and Pressure Differential Transmitter PDT-33111 the tube side. The associated Pressure Differential Indicators PDI-33110 and PDI-33111 provide high differential alarm function at the ICSS.

Pressure Transmitter PT-33103A2 and its associated Pressure Indicator PI-33103A2 provide the high pressure alarm function for Pre-Heater 5-EC-3310A.

For Pre-Heater 5-EC-3310A a Pressure Transmitter PT-33112A2 and its associated Pressure Switch PS-33112A2 provide high-high pressure indication to the PSS and trip the system.

Pressure Differential Gauges PDG-33108A monitors the pressure drop through the Crude Oil Pre-Heater 5-EC-3310A tube side and PDG-33102A the shell side.





3.4.2 Temperature

Local Temperature Gauges TG-33101A, TG-33105A, TG-33107A and TG-33109A show the inlet and outlet temperatures at Pre-Heater 5-E-3310A.

3.4.3 Safeguarding


A 6” Shutdown Valve SDV-33114 is located on the condensate return line to the pre-heaters from the MP compressor scrubber pumps.

A 3” Shutdown Valve SDV-33115 is located on the condensate return line to the pre-heaters from the LP compressor scrubber pumps.

Crude Oil Pre-Heater 5-EC-3310A tube side is equipped with 2 x 100% Pressure Safety Valves, PSV1-33106A and PSV2-33106A, both sized for tube rupture

Crude Oil Pre-Heater 5-EC-3310B tube side is equipped with 2 x 100% Pressure Safety Valves, PSV1-33106B and PSV2-33106B, also sized for tube rupture.

A locked open and locked closed block valve arrangement allows for on-line maintenance of the PSVs.

Both Crude Oil Pre-Heaters shell sides are equipped with a PSV-33104A and PSV-33104B respectively and sized for the fire case. Spare fire case PSVs are stored in the workshop.

All the Crude Oil Pre-Heaters pressure safety valves relieve to HP warm temperature flare collection system. The valve settings are detailed in Paragraph 3.14 Pressure Safety Valve Settings.

For details of the emergency shutdown/s associated with the Crude Oil Pre-Heaters 5-EC-3310A1/A2/B1/B2 refer to NG50-5-500-PRO-PS-AB-0000-0060, Emergency Shutdown Diagrams.





3.5 Crude Oil Heaters 5-EC-3320- A1/2B1/2

Refer to: P&ID NG50-5-500-PRO-PI-AB-33-0002 – Crude Oil Heaters

NOTES: The Crude Oil Heaters 5-EC-3320A1/2B1/2 are identical in construction and service. This paragraph mainly details 5-EC-3320A1/2. For Tagging differences, refer to P&ID

Manual valves allow bypass of individual units.

With the oil heating not operating this could prevent achieving both the BS&W and the RVP specifications. The associated production should be stored in the dedicated off-spec crude cargo tanks for further reprocessing. The duration of such mode of operation should be limited.


Shell Side Tube Side Inlet Outlet Inlet Outlet Total Flow 76861kg/hr (for one unit) 587200kg/hr (for one unit)

Oil 534600kg/hr 522300kg/hr

Water 76861kg/hr 76861kg/hr 37480kg/hr 36540kg/hr

Vapour 15110kg/hr 28360kg/hr

Operating Pressure 11.7barg 11.2barg 9barg 8barg

Operating Temperature 158°C 77°C 73.7°C 90°C

3.5.1 Pressure

The crude oil side (tube) pressure drop through Crude Oil Heaters 5-EC-3320A and 5-EC-3320B is monitored by Pressure Differential Transmitter PDT-33210. Pressure Differential Indicator PDI-33210 provides high differential pressure alarm.

Pressure Differential Gauge PDG-33202A monitors the pressure drop through the tube side of Crude Oil Heater 5-EC-3320A.

Pressure Transmitter PT-33203A and Pressure Indicator PI-33203A provide the high and low pressure alarm function for Heater 5-EC-3320A.

Pressure Transmitter PT-33217A and Pressure Switch PS-33217A provide the high-high pressure indication to the PSS for Heater 5-EC-3320A.

Pressure Transmitter PT-33220 and Pressure Switch PS-33220A provide the high-high pressure indication to the PSS for the 10” off-spec product from the cargo tanks.

Pressure Element PE-33212 and PE-33213 are located on the 10” off-spec product from the cargo tanks for testing of the leakage rate and tightness of the check valves.





3.5.2 Temperature

A Temperature Indicator Controller TIC-33214 normally set at 90°C, controls outlet temperature of crude oil tube side by regulating the hot water flowrate through shell side acting on Temperature Control Valve TV-33214. A Temperature Transmitter TT-33214 and the Temperature Indicator Controller TIC-33214 also monitor and indicate a high and low temperature alarm.

Temperature Transmitter TT-33212 and Temperature Switch TS-33212 provide high-high temperature indication at the heaters crude oil outlet to the 3rd Stage Separator.

Local Temperature Gauges TG-33201A, TG-33205A, TG-33207A and TG-33209A show the inlet and outlet temperatures of crude oil and hot water respectively at Heater 5-E-3320A.

Temperature Gauge TG-33213 indicates the common outlet temperature to the 3rd Stage Separator.

Temperature Transmitter TT-33202 and Temperature Indicator TI-33202 provide high temperature indication at the 24” incoming line from the Crude Oil Pre-heaters.

3.5.3 Flow

Flow Element FEP-33222, Flow Transmitter FT-33222 and Flow Indicator FI-33222 are located at the 10” off-spec product line from the cargo tanks.

3.5.4 Safeguarding


A 24” Shutdown Valve SDV-33218 is provided at the inlet to the crude oil heaters from the crude oil pre-heaters.

A 12” Shutdown Valve SDV-33215 is provided at the inlet to the crude oil heaters from the hot water distribution system. A 12” Shutdown Valve SDV-33216 is provided from the crude oil heaters outlet to the hot water system. A 10” Shutdown Valve SDV-33219 is located on the off-spec product line from the cargo tanks.

Crude Oil Heater 5-EC-3320A is equipped with two Pressure Safety Valves:

• PSV-33204A sized for fire case

• PSV-33206A sized for tube rupture

Crude Oil Heater 5-EC-3320B is equipped with two Pressure Safety Valves:

• PSV-33204B sized for fire case

• PSV-33206B sized for tube rupture





The 10” off-spec product line from the hull reprocessing is provided with 2 100% Pressure Safety Valves PSV1-33221 and PSV2-33221 sized for check valve backflow.

The pressure safety valves relieve to HP warm temperature flare collection system.

The valve settings are detailed in Paragraph 3.14 Pressure Safety Valve Settings.

For details of the emergency shutdown/s associated with the Crude Oil Heaters 5-EC-3320A/B refer to NG50-5-500-PRO-PS-AB-0000-0060, Emergency Shutdown Diagrams.





3.6 3rd Stage Separator 5-DS-3410

Refer to Drawing Number: NG50-5-500-PRO-PI-AB-34-0001 - 3rd Stage Separator 5-DS-3410

3.6.1 Pressure

Pressure at 3rd Stage Separator is monitored by Pressure Transmitter PT-34111 and controlled by Pressure Indicator Controller PIC-34111 in split range to control:

• Pressure Valve PV1-34111 - gas to HP warm flare temperature collection system if pressure increase above the set point

• Pressure Valve PV2-34111 - gas to MP compressor suction coolers and maintains separator pressure at 8barg

Pressure Indicator Controller PIC-34111 also provides a surge anticipation signal, via Pressure Selector PY-34111, to relay the MP compressor antisurge control.

Pressure Transmitter PT-34110 and Pressure Switch PS-34110 provide PSS signals for low-low and high-high separator pressure.

Pressure Gauge PG-34109 provides local pressure indication at the separator.

3.6.2 Temperature

Temperature Transmitter TT-34103 and Temperature Indicator TI-34103 provide temperature correction for the gas flow totaliser FQI-34113.

A local Temperature Gauge TG-34104 indicates separator temperature.

3.6.3 Level

Oil Level

Level Indicator Controller LIC-34105 controls the oil level in the 3rd Stage Separator. The controller acts on the 2 x 100% Level Valves LV1-34105 or LV2-34105 located on the oil line from the electrostatic dehydrator via a Low Selector LY-34105. The selector uses the lowest signals from LIC-34105 and the electrostatic dehydrator Pressure Indicator Controller PIC-36104. The selector selects operation of LV1-34105 or LV2-34105 or overrides the control of LIC-34105 in case of low pressure in electrostatic dehydrator as signaled by PIC-36104. The override is necessary because pressure in the dehydrator is critical to avoid any gas break out in the dehydrator vessel.

Level Transmitter LT-34101 and Level Switch LS-34101 provide high-high and low-low signals to the PSS.

Local Level Gauges LG1-34102 and LG2-34102 indicate separator oil level.






Level Differential Transmitter LDT-34106 and Level Differential Interface Controller LDIC-34106 controls water level in the 3rd Stage Separator by modulating Level Differential Valve LDV-34106 in the 6” produced water outlet to the oily water drum. A 4” manual bypass is provided around LDV-34106.

Level Differential Transmitter LDT-34108 and Level Differential Switch LDS-34108 provide low-low interface signals to the PSS.

Level Differential Gauge LDG-34107 provides local indication of the oil/water interface level.

3.6.4 Flow

A Flow Meter FEX-34113, Flow Transmitter FT-34113 and Flow Totaliser Indicator FQI-34113 monitor and record the gas flowrate from the separator to the MP compression.

A Flow Meter FEX-34119, Flow Transmitter FT-34119 and Flow Totaliser Indicator FQI-34119 monitor and record the produced water flowrate from the separator to the oily water drum.

3.6.5 Safeguarding


A 6” Emergency Blowdown Valve EBDV-34123 is provided at the gas outlet to the HP flare warm temperature collection system.

A 16” Shutdown Valve SDV-34121, together with its start-up bypass Shutdown Valve SDV-34133 and Pressure Differential Transmitter PDT-34131 are located on the gas outlet line to the MP compressor suction cooler.

A Shutdown Valve SDV-34117 is located on the 24” crude outlet line to the 3rd Stage Separator Pumps.

A failed closed Shutdown Valve SDV-34120 is located on the 6” produced water outlet line to the oily water drum.

The 3rd Stage Separator 5-DS-3410 is equipped with 3 x 50% Pressure Safety Valves:

• PSV1-34124 sized for blocked outlet



The pressure safety valves relieve to HP warm temperature flare collection system.


For details of the emergency shutdown/s associated with the 3rd Stage Separator 5-DS-3410 refer to NG50-5-500-PRO-PS-AB-0000-0060, Emergency Shutdown Diagrams.





3.7 3rd Stage Separator Pumps 5-GX-3410A/B

Refer to Drawing Number: NG50-5-500-PRO-PI-AB-34-0001 - 3rd Stage Separator

NOTE: The 3rd Stage Separator Pumps 5-GX-3410A/B are identical in construction and service. This paragraph mainly details 5-GX-3410A. For Tagging differences, refer to P&ID: NG50-5-500-PRO-PI-AB-34-0001 - 3rd Stage Separator

Oil from 3rd Stage Separator is sent to Electrostatic Dehydrator by the 3rd Stage Separator Pumps. Injection water is introduced upstream of the pump Inlet to maintain the required minimum 5% water fraction in the liquids sent to the Dehydrator.

The pumps are selected at the local motor control centre or via the PCS.

3.7.1 Pressure

The pumps operate at 12.5barg discharge pressure. Pump 5-GX-3410A is supplied with Pressure Transmitter PT-34116A and Pressure Switch PS-34116A to monitor and signal low-low and high-high pressure to the PSS. The pump tripped on high-high pressure.

Pump 5-GX-3410A inlet pressure is shown at PG-34112A and the outlet pressure at PG-34114A.

Pressure Transmitter PT-34127 and Pressure Indicator PI-34127 monitor the pressure in the common 16” outlet to the electrostatic dehydrator and provide low and high pressure signals to the PCS.

3.7.2 Flow

Flow Transmitter FT1-34118A located at the pumps16” discharge line monitors crude oil flow from the pump and provides a low-low flow pump trip.

From Flow Transmitter FT2-34118A, Flow Indicator Controller FIC-34118A modulates Flow Valve FV-34118A to control the 10” pump minimum flow recycle line back to the separator inlet.

Flow Indicator FIC-35116 acting on Flow Valve FV-35116 controls injection water flow from the water injection booster pumps. The set point of FIC-35116 is fixed by the flow ratio converter FY-35116 which ensure a minimum BS&W of 5% at dehydrator inlet.

Pump cooling water flow is regulated operating the glob valve and visually checking the water flow indicator glass.

3.7.3 Leakage Control System

Outputs from the Leakage Control System are as follows:

• LT-35250A Liquid level signal from leakage collecting tank


• PT-35250A Pressure level inside the leakage collecting tank





PT-35251A Pressure level inside the leakage collecting tank

3.7.4 Safeguarding


A 16” Shutdown Valve SDV-34130 is located on the crude oil common outlet line of the 3rd Stage Separator Pumps.

A 3” Shutdown Valve SDV-34101 is located on the injection water inlet to the pumps.

The to protect the pumps each 3rd Stage Separator Pumps 5-GX-3410A and 5-GX-3410B are equipped with a minimum flow line back to the separator inlet.

For details of the emergency shutdown/s associated with the 3rd Stage Separator Pumps 5-GX-3410A and 5-GX-3410B refer to NG50-5-500-PRO-PS-AB-0000-0060, Emergency Shutdown Diagrams.





3.8 Electrostatic Dehydrator 5-DS-3510

Refer to Drawing Number: NG50-5-500-PRO-PI-AB-35-0001 - Electrostatic Dehydrator 5-DS-3510

On/Off control of the power units is from the PCS the Electrostatic Dehydrator Local Panel 5-LP-3510 is for indication.

NOTE: If the Electrostatic Dehydrator is not operational for any reason a 16” bypass can be used but the BS&W specification may not be achieved. In this case the production should be loaded in the off-spec crude cargo tanks. Alternatively off-spec crude can still be off-loaded with penalties applicable for not meeting the BSW specification. The BSW specification may also be achievable in the cargo tanks by natural settling.

At the Electrostatic Dehydrator the water and oil mixture enters below the electrodes and is immediately subjected to an electrical field set up between the lower electrodes and the grounded electrodes located at the interfaces. This electrical field is strong enough to coalesce and separate the water droplets. The water collects at the bottom of the vessel and is passed under level control to the Oily Water Drum 5-DS-4110. Oil is passed under level control from the 3rd Stage Separator Level Indicator Controller LIC-34105 to the 4th Stage Separator 5-DS-3610.

If the pressure in the vessel is lower then the vapor pressure or the total liquid level decreases by 50mm from top of the vessel, the power units will be shutdown.

3.8.1 Pressure

Differential Pressure Indicator Controller PDIC-35113 signalled by Pressure Differential Indicator Transmitter PDIT-35113 controls mixing Pressure Differential Valve PDV-35113 at crude oil dehydrator inlet to ensure correct mixing. If the differential pressure is high, the control valve opens.

Pressure Transmitter PT-35104 and Pressure Indicator Controller PIC-35104 control the dehydrator pressure by influencing the 3rd Stage Separator Level Indicator Controller LIC-34106 via selector LY-34105.

Pressure Transmitter PT-35109 and Pressure Switch PS-35109 provide low-low pressure signals to the PSS.

Each power supply unit is provided with a high-high Pressure Switch, PS-35150A and PS-35150A respectively linked to the PSS.

A local Pressure Gauge PG-35102 indicates the dehydrator vessel pressure.

3.8.2 Temperature

Temperature Transmitter TT-35106 signals Temperature Indicator TI-35106 to provide high and low indication.

Each power supply unit is provided with a high-high Temperature Switch, TS-35150A and TS-35150A respectively linked to the PSS.

Temperature Gauge TG-35107 indicates the dehydrator vessel temperature.





3.8.3 Level

Interface Differential Level Controller LDIC-35103 controls interface oil/water level in the dehydrator.

Level Differential Transmitter LDT-35108 and Level Differential Switch LDS-35108 provide high-high and low-low differential shut down alarms to the PSS.

Level Transmitter LT-35101 and Level Switch LS-35101 provide low-low dehydrator vessel level signals the PSS.

3.8.4 Flow

To achieve a minimum BS&W of 5% at the dehydrator inlet, oil and water flowrate at the dehydrator outlet are measured by Flow Transmitter FT-35111 on the oil outlet and Flow Transmitter FT-35116 on the water outlet. The associated Flow Indicators FI-35111 and FI-35116 both signal flow ratio converter FY-35116 that uses the water/oil ratio to fix the set point of wash water flowrate to be injected by the means of water Flow Indicator Controller FIC-35116.

3.8.5 Safeguarding


A Shutdown Valve SDV-35114 is located on the 16” crude oil inlet line to the dehydrator from the 3rd Stage Separator.

A Shutdown Valve SDV-35110 is located on the 16” crude oil outlet line from the dehydrator to the 4th Stage Separator.

A Shutdown Valve SDV-35115 is located on the 6” water outlet line from the dehydrator to the oily water drum.

The Electrostatic Dehydrator 5-DS-3510 is equipped with a Pressure Safety Valve PSV-35117. The PSV is sized for the fire case and relieves to the HP warm temperature flare collection system. A locked open block and vent valve and a manual 2” bypass line are provided. The PSV setting is detailed in Paragraph 3.14 Pressure Safety Valve Settings.

For details of the emergency shutdown/s associated with the Electrostatic Dehydrator 5-DS-3510 refer to NG50-5-500-PRO-PS-AB-0000-0060, Emergency Shutdown Diagrams.





3.9 4th Stage Separator 5-DS-3610


3.9.1 Pressure

Refer to: P&ID NG50-5-500-PRO-PI-AB-51-0002 – LP Compressor

Two independent pressure controllers are used to control the pressure in the 4th Stage Separator at 1barg.

Under normal conditions, with the LP Compressor 5-KB-5140 operating, Pressure Indicator Controller PIC-36111 acts in split range opening the fail closed LP compressor Pressure Valve PV1-36111. When the LP compressor reaches maximum loading or trips the flare Pressure Valve PV2-36111 is opened directing gas to the LP flare collection system.

In case of 4th Stage Separator high pressure, or when the LP compressor is not operating, Pressure Indicator Controller PIC-36112 directs the Pressure Valve PV-36112 open to route the gas direct to the LP flare collection system.

Pressure Gauge PG-36109 indicates 4th Stage Separator pressure.

Pressure Transmitter PT-36110 and Pressure Switch PS-36110 indicate high and low-low pressure to the PSS.

3.9.2 Temperature

Temperature Gauge TG-36104 indicates the 4th Stage Separator temperature.

3.9.3 Level


Level Transmitter LT-36105 and Level Indicator Controller LIC-36105 control the oil level in the separator by modulating Level Valves LV1-36105 or LV2-36105. The 2 x 100% control valves are located on the oil line downstream from the Crude Oil Coolers 5-EC 3710A/B/C. Selector LZ-36105 uses the liquid level signal from LIC-36105 to direct s the operation of either Level Valve LV1-36105 or LV2-36105.

Level Transmitter LT-36101 and Level Switch LS-36101 provide the high-high and low-low level signals to the PSS.

Level Gauges LG1-36103 and LG2-36103 indicate the separator vessel levels.

3.9.4 Flow

Flow Transmitter FT-36113 is used to monitor gas flow at the 4th Stage Separator outlet with Flow Totaliser Indicator FQI-36113.





3.9.5 Safeguarding


A Shutdown Valve SDV-36117 is located on the 24” crude outlet from the separator to the crude oil transfer pumps.

A Shutdown Valve SDV-36121 is located on the 20” gas outlet line from the separator to the LP compressor suction cooler.

The 4th Stage Separator 5-DS-3410 is equipped with 3 x 50% Pressure Safety Valves:




The pressure safety valves relieve to LP flare collection system.


For details of the emergency shutdown/s associated with the 4th Stage Separator 5-DS-3610 refer to NG50-5-500-PRO-PS-AB-0000-0060, Emergency Shutdown Diagrams.





3.10 Crude Oil Transfer Pumps 5-GX-3720A/B


NOTE: Crude Oil Transfer Pumps 5-GX-3720A/B are identical in construction and service. This paragraph mainly details 5-GX-3720A. For Tagging differences, refer to P&ID

The standby pump automatically starts on loss of the duty pump. The pumps are operated locally or remotely from the PCS.

3.10.1 Pressure

Crude Oil Transfer Pump 5-GX-3720A Pressure Gauge PG-37201A indicates the pump inlet pressure and Pressure Gauge PG-37202A indicates the outlet pressure.

Pressure Transmitter PT-37203A and Pressure Switch PS-37203A provide Crude Oil Transfer Pump 5-GX-3720A and low-low and high-high pressure signals to the PSS.

Pressure Transmitter PT-37204 and Pressure Switch PS-37204 provide high and low pressure signals to the PCS for the common 18” crude oil discharge line.

3.10.2 Flow

A Flow Indicator Controller FIC-37201A located at Crude Oil Transfer Pump 5-GX-3720A discharge protects the pump. The controller acts on Flow Valve FV-37201A located on the pumps minimum flow line, which allows recycling of crude oil back to the inlet of the to 4th Stage Separator.

Pump cooling water flow is regulated operating the glob valve and visually checking the water flow indicator glass.

3.10.3 Leakage Control System

Outputs from the Leakage Control System are as follows:





3.10.4 Safeguarding


The Crude Oil Transfer Pumps 5-GX-3720A and 5-GX-3720B are equipped with a minimum flow line back lines to the separator.





For details of the emergency shutdown/s associated with the Crude Oil Transfer Pumps 5-GX-3720A and 5-GX-3720B refer to NG50-5-500-PRO-PS-AB-0000-0060, Emergency Shutdown Diagrams.





3.11 Crude Oil Coolers 5-EC-3710A/B/C


NOTES: Crude Oil Coolers 5-EC-3710A/B/C are identical in construction and service. This paragraph mainly details 5-EC-3710A. For Tagging differences, refer to P&ID

Normal operation is with two coolers operating and one on standby.

If the crude oil coolers are not operating, the temperature of the crude entering the cargo tanks will be a maximum of approximately 80°C. A temperature trip is provided downstream the crude oil coolers to avoid oil production without cooling. If the reception cargo tanks are partially filled it may be acceptable to continue the loading operation to the cargo tanks, since the thermal inertia of the cooled tank contents will be large. However, the duration of this degraded operation should be strictly limited and loading operation can continue provided overall crude temperature is less than 60°C to avoid damage to the tank coating.

The quality of stabilised oil sent to the storage tanks is supervised by the in-line BS&W Analyser AI-37111, located downstream of the coolers. An indication of BS&W of <0.3% indicates good operation of the oil separation train.


Cold Side Hot Side Inlet Outlet Inlet Outlet Total Flow 116301kg/hr (for one unit) 242562kg/hr (for one unit)

Oil 242562kg/hr 242562kg/hr

Water 116301kg/hr 116301kg/hr - -

Operating Pressure 7barg 6barg - -

Operating Temperature 28°C 45°C 57°C 40°C

3.11.1 Pressure

Pressure Differential Transmitter PDT-37107 and Pressure Differential Indicator PDI-37107 signal a high differential pressure across the common crude oil inlet and common outlet.

Pressure Differential Gauge PDG-37102A indicates the pressure differential across the crude oil inlet an outlet at Crude Oil Cooler 5-EC-3710A.

Pressure Elements PE-37103A and PE-37104A provide a provision for the attachment of portable digital pressure test equipment at the cooling water inlet and outlet of Crude Oil Cooler 5-EC-3710A.

3.11.2 Temperature





Temperature Indicator Controller TIC-37108 normally set at 40°C controls the temperature of the crude oil sent to the storage cargo tanks. The controller modulates Temperature Valve TV-37108 to control the cooling water flow through the coolers.

Temperature Gauge TG-37101A indicates the outlet crude oil temperature leaving Crude Oil Cooler 5-EC-3710A.

Temperature Gauge TG-37103A indicates the outlet water temperature leaving Crude Oil Cooler 5-EC-3710A.

Temperature Transmitter TT-37109 and Temperature Switch TS-37109 signal to PSS on high-high crude oil temperature at the 18” common discharge to loading manifold.

Temperature Gauge TG-37106 indicates the common inlet water temperature.

3.11.3 Flow

Flow Totaliser Indicator FQI-37110 is used to monitor oil flowrate sent to crude storage cargo tanks with flow transmitters FT-37110.

The BS&W Analyser Transmitter AT-37111 and Analyser Indicator AI-37111 monitor the crude oil discharge to the loading manifold BS&W. Analyser Alarm AA-37111 provides warning of a high BS&W.





3.11.4 Safeguarding


An Emergency Shutdown Valve ESDV-37113 is located on the 18” crude discharge to the loading manifold. A Shutdown Valve SDV-37112 is also located on the 18” crude discharge to the loading manifold.

The coolers are equipped with temperature and pressure safety valves as follows:

• Crude Oil Cooler 5-EC-3710A:

TSV-37104A on the water side is sized for thermal expansion and relieves to the local drip tray

PSV-37105A on the oil side is sized for the fire case and relieves to the HP flare

• Crude Oil Cooler 5-EC-3710B:

TSV-37104B on the water side is sized for thermal expansion and relieves to the local drip tray

PSV-37105B on the oil side is sized for fire case and relieves to the HP flare

• Crude Oil Cooler 5-EC-3710C:

TSV-37104C on the water side is sized for thermal expansion and relieves to the local drip tray

PSV-37105C on the oil side is sized for fire case and relieves to the HP flare


For details of the emergency shutdown/s associated with the Crude Oil Coolers 5-EC-3720A/B/C refer to NG50-5-500-PRO-PS-AB-0000-0060, Emergency Shutdown Diagrams.





3.12 System Control and Setpoints

Tag Number Service Setpoint/Range

PIC-31111A/B 1st Stage Separators 5-DS-3110A/B Pressure 85barg

PIC-31112A/B 1st Stage Separators 5-DS-3110A/B Pressure 79barg

LIC-31105A/B 1st Stage Separators 5-DS-3110A/B Crude Oil 2100mm

LDIC-31106A/B 1st Stage Separators 5-DS-3110A/B Interface Level 500mm

FIC-31113A/B 1st Stage Separators 5-DS-3110A/B Gas Flow 3554m³/h

FIC-31118A/B 1st Stage Separators 5-DS-3110A/B Oil Flow 863m³/h

PIC-31212 Test Separator 5-DS-3120 Pressure 85barg

PIC-31211 Test Separator 5-DS-3120 Pressure (HP Mode) 79barg

FIC-31213 Test Separator 5-DS-3120 Gas Flow (HP Mode) 372m³/h

LIC-31205 Test Separator 5-DS-3120 Crude Oil 1600mm

LDIC-31206 Test Separator 5-DS-3120 Interface Level 800mm

PIC-32111 2nd Stage Separator 5-DS-3210 Pressure 22.5barg

LIC-32105 2nd Stage Separator 5-DS-3210 Crude Oil 2100mm

LDIC-32106 2nd Stage Separator 5-DS-3210 Interface Level 500mm

TIC-33214 Crude Oil Heaters 5-EC-3320A/B Water Temperature 90°C

PIC-34111 3rd Stage Separator 5-DS-3410 Pressure 8barg

LIC-34105 3rd Stage Separator 5-DS-3410 Crude Oil 2660mm

LDIC-34106 3rd Stage Separator 5-DS-3410 Interface Level 500mm

FIC-34118A/B 3rd Stage Separator Pumps 5-GX-3410A/B Minimum Flow

743m³/h

LDIC-35103 Electrostatic Dehydrator 5-DS-3510 Interface Level 1000mm

PIC-35104 Electrostatic Dehydrator 5-DS-3510 Pressure 8.8barg

PDIC-36113 Electrostatic Dehydrator 5-DS-3510 Differential Pressure 0.7barg

FIC-35116 Electrostatic Dehydrator 5-DS-3510 Water/Oil Flow Ratio 5

PIC-36111 4th Stage Separator 5-DS-3610 Pressure 1barg

PIC-36112 4th Stage Separator 5-DS-3610 Pressure 1.5barg

LIC-36105 4th Stage Separator 5-DS-3610 Oil Level 1660mm

FIC-37201A/B Crude Oil Transfer Pumps 5-GX-3720A/B Minimum Flow 625m³/h

TIC-37108 Crude Oil Coolers 5-EC-3710A/B/C 40°C





3.13 Alarm and Trip Settings

Tag Number Service Setpoint

PAHH-3110A/B 1st Stage Separators 5-DS-3110A/B Pressure 87barg

PALL-3110A/B 1st Stage Separators 5-DS-3110A/B Pressure 60barg

PAH-31111A/B 1st Stage Separators 5-DS-3110A/B Pressure 85barg

PAL-31111A/B 1st Stage Separators 5-DS-3110A/B Pressure 76barg

PAH-31112A/B 1st Stage Separators 5-DS-3110A/B Pressure 85barg

PAL-31112A/B 1st Stage Separators 5-DS-3110A/B Pressure 76barg

LAH-31105A/B 1st Stage Separators 5-DS-3110A/B Oil Level 2600mm

LAL-31105A/B 1st Stage Separators 5-DS-3110A/B Oil Level 1700mm

LAHH-31101A/B 1st Stage Separators 5-DS-3110A/B Oil Level 2830mm

LALL-31101A/B 1st Stage Separators 5-DS-3110A/B Oil Level 1500mm

LAH-31106A/B 1st Stage Separators 5-DS-3110A/B Interface Level 700mm

LAL-31106A/B 1st Stage Separators 5-DS-3110A/B Interface Level 400mm

LALL-31108A/B 1st Stage Separators 5-DS-3110A/B Interface Level 300mm

FAH-31113A/B 1st Stage Separators 5-DS-3110A/B Gas Flow 5100m³/h

FAL-31113A/B 1st Stage Separators 5-DS-3110A/B Gas Flow 3100m³/h

TAH-31103A/B 1st Stage Separators 5-DS-3110A/B Temperature 80°C

TAL-31103A/B 1st Stage Separators 5-DS-3110A/B Temperature 45°C

PAHH-31210 Test Separator 5-DS-3120 Pressure 87barg

PALL-31210 Test Separator 5-DS-3120 Pressure 15barg

PAH-31212 Test Separator 5-DS-3120 Pressure 85barg

PAL-31212 Test Separator 5-DS-3120 Pressure 76barg

PAHH-31206 Test Separator 5-DS-3120 Oil Pressure to Pre-Heaters 5-EC-3310A1/A2/B1/B2

30barg

PAHH-31207 Test Separator 5-DS-3120 Gas Pressure 30barg

LAH-31205 Test Separator 5-DS-3120 Oil Level 2200mm

LAL-31205 Test Separator 5-DS-3120 Oil Level 1200mm

LAHH-31201 Test Separator 5-DS-3120 Oil Level 2380mm

LALL-31201 Test Separator 5-DS-3120 Oil Level 1000mm

LAH-31206 Test Separator 5-DS-3120 Interface Level 2200mm

LAL-31206 Test Separator 5-DS-3120 Interface Level 500mm

LALL-31208 Test Separator 5-DS-3120 Interface Level 300mm






FAH-31213 Test Separator 5-DS-3120 Gas Flow 400m³/h

FAL-31213 Test Separator 5-DS-3120 Gas Flow 240m³/h

TAH-31203 Test Separator 5-DS-3120 Temperature 110°C

TAL-31203 Test Separator 5-DS-3120 Temperature 30°C

PAHH-31210 2nd Stage Separator 5-DS-3210 Pressure 25barg

PALL-31210 2nd Stage Separator 5-DS-3210 Pressure 15barg

PAH-31211 2nd Stage Separator 5-DS-3210 Pressure 24bar

PAL-31211 2nd Stage Separator 5-DS-3210 Pressure 20barg

LAH-32105 2nd Stage Separator 5-DS-3210 Oil Level 2660mm

LAL-32105 2nd Stage Separator 5-DS-3210 Oil Level 1900mm

LAHH-32101 2nd Stage Separator 5-DS-3210 Oil Level 3000mm

LALL-32101 2nd Stage Separator 5-DS-3210 Oil Level 1500mm

LAH-32106 2nd Stage Separator 5-DS-3210 Interface Level 600mm

LAL-32106 2nd Stage Separator 5-DS-3210 Interface Level 400mm

LALL-32108 2nd Stage Separator 5-DS-3210 Interface Level 300mm

TAH-32103 2nd Stage Separator 5-DS-3210 Temperature 65°C

TAL-32103 2nd Stage Separator 5-DS-3210 Temperature 40°C

PAH-33103A2/B2 Crude Oil Pre-Heaters 5-EC-3310A/B Pressure 10barg

PAHH-331112A2/B2

Crude Oil Pre-Heater 5-EC-3310A/B Tube Rupture 12.5barg

PDAH-33110 Crude Oil Pre-Heaters 5-EC-3310A/B Shell Differential Pressure

1.5bar

PDAH-33111 Crude Oil Pre-Heaters 5-EC-3310A/B Tube Differential Pressure

1.5bar

PAH-33203A/B Crude Oil Heaters 5-EC-3320A/B Pressure 7.5bar

PAHH-33203A/B Crude Oil Heaters 5-EC-3320A/B Pressure 16bar

PAHH-33217A/B Crude Oil Heaters 5-EC-3320A/B Tube Rupture 17barg

PDAH-33210 Crude Oil Heaters 5-EC-3320A/B Oil Side Differential Pressure

1.5bar

TAH-33214 Crude Oil Heaters 5-EC-3320A/B Temperature 95°C

TAL-33214 Crude Oil Heaters 5-EC-3320A/B Temperature 82°C

TAHH-33212 Crude Oil Heaters 5-EC-3320A/B Outlet Temperature 100°C

PAHH-34110 3rd Stage Separator 5-DS-3410 Pressure 11barg

PALL-34110 3rd Stage Separator 5-DS-3410 Pressure 4barg






PAH-34111 3rd Stage Separator 5-DS-3410 Pressure 9barg

PAL-34111 3rd Stage Separator 5-DS-3410 Pressure 7barg

LAH-34105 3rd Stage Separator 5-DS-3410 Oil Level 2650mm

LAL-34105 3rd Stage Separator 5-DS-3410 Oil Level 1900mm

LAHH-34101 3rd Stage Separator 5-DS-3410 Oil Level 3000mm

LALL-34101 3rd Stage Separator 5-DS-3410 Oil Level 1500mm

LAH-34106 3rd Stage Separator 5-DS-3410 Interface Level 800mm

LAL-34106 3rd Stage Separator 5-DS-3410 Interface Level 400mm

LALL-34108 3rd Stage Separator 5-DS-3410 Interface Level 300mm

FAH-34113 3rd Stage Separator 5-DS-3410 Gas Flow HOLD

TAH-34103 3rd Stage Separator 5-DS-3410 Temperature HOLD

TAL-34103 3rd Stage Separator 5-DS-3410 Temperature HOLD

PSHH-34116A/B 3rd Stage Separator Pumps 5-GX-3410A/B Pressure 15bar

PSLL-34116A/B 3rd Stage Separator Pumps 5-GX-3410A/B Pressure 7barg

FAH-34118A/B 3rd Stage Separator Pumps 5-GX-3410A/B Flow 720m³/h

PAHH-34150A/B 3rd Stage Separator Pumps 5-GX-3410A/B Leakage

Detection

0.91barg

PH-34150A/B 3rd Stage Separator Pumps 5-GX-3410A/B Leakage

Detection

0.7barg

PSH-34127 3rd Stage Pumps 5-GX-3410A/B Common Discharge Pressure

14barg

PSL-34127 3rd Stage Pumps 5-GX-3410A/B Common Discharge Pressure

9barg

PALL-35109 Electrostatic Dehydrator 5-DS-3510 Pressure 8.5barg

PAH-35104 Electrostatic Dehydrator 5-DS-3510 Pressure 15barg

PAL-35104 Electrostatic Dehydrator 5-DS-3510 Pressure 8.5barg

LALL-35101 Electrostatic Dehydrator 5-DS-3510 Interface Level (Stop Transformer)

3550mm

LAHH-35108 Electrostatic Dehydrator 5-DS-3510 Interface Level (Stop Transformer)

1400mm

LALL-35108 Electrostatic Dehydrator 5-DS-3510 Interface Level (Close SDV)

600mm

LAL-35103 Electrostatic Dehydrator 5-DS-3510 Interface Level 800mm

LAH-35103 Electrostatic Dehydrator 5-DS-3510 Interface Level 1200mm





PDAH-35113 Electrostatic Dehydrator 5-DS-3510 Differential Pressure

1.3barg

PDAL-35113 Electrostatic Dehydrator 5-DS-3510 Differential Pressure

0.5barg

FAH-35116 Electrostatic Dehydrator 5-DS-3510 Water/Oil Ratio 10

FAL-35116 Electrostatic Dehydrator 5-DS-3510 water/Oil Ratio 4.8

TAH-35106 Electrostatic Dehydrator 5-DS-3510 Temperature 95°C

TAL-35106 Electrostatic Dehydrator 5-DS-3510 Temperature 85°C

PAHH-35150A Electrostatic Dehydrator 5-DS-3510, Power Unit 5-DS-3510-PU1 Pressure

HOLD

TAHH-35150A Electrostatic Dehydrator 5-DS-3510, Power Unit 5-DS-3510-PU1 Temperature

HOLD

PAHH-35150B Electrostatic Dehydrator 5-DS-3510, Power Unit 5-DS-3510-PU2 Pressure

HOLD

TAHH-35150B Electrostatic Dehydrator 5-DS-3510, Power Unit 5-DS-3510-PU2 Temperature

HOLD

PAHH-3610 4th Stage Separator 5-DS-3610 Pressure 5barg

PALL-3610 4th Stage Separator 5-DS-3610 Pressure 0.3barg

PAH-36111 4th Stage Separator 5-DS-3610 Pressure 1.5barg

PAL-36111 4th Stage Separator 5-DS-3610 Pressure 0.7barg

LAHH-36101 4th Stage Separator 5-DS-3610 Oil Level 2450mm

LALL-36101 4th Stage Separator 5-DS-3610 Oil Level 600mm

LAH-36105 4th Stage Separator 5-DS-3610 Oil Level 2050mm

LAL-36105 4th Stage Separator 5-DS-3610 Oil Level 1250mm

PAHH-37203A/B Crude Oil Transfer Pumps 5-GX-3720A/B Pressure 4.6barg

PALL-37203A/B Crude Oil Transfer Pumps 5-GX-3720A/B Pressure 0.5barg

FAH-37201A/B Crude Oil Transfer Pumps 5-GX-3720A/B Flow 1700m³/h

FAL-37201A/B Crude Oil Transfer Pumps 5-GX-3720A/B Flow 615m³/h

PAH-37204 Crude Oil Transfer Pumps 5-GX-3720A/B Common Pressure

5barg

PAHH-37251A/B Crude Oil Transfer Pumps 5-GX-3720A/B Leakage

Detection

0.72barg

PAH-37251A/B Crude Oil Transfer Pumps 5-GX-3720A/B Leakage

Detection

0.6barg

PAL-37204 Crude Oil Transfer Pumps 5-GX-3720A/B Common Pressure

1.5barg





PDH-37107 Crude Oil Coolers 5-EC-3710A/B/C Differential Pressure

1.5bar

TAHH-37109 Crude Oil Coolers 5-EC-3710A/B/C Outlet Temperature 60°C

TAH-37108 Crude Oil Coolers 5-EC-3710A/B/C Outlet Temperature 50°C

TAL-37108 Crude Oil Coolers 5-EC-3710A/B/C Outlet Temperature 30°C

AH-37111 Crude Oil Coolers 5-EC-3710A/B/C BS&W HOLD





3.14 Pressure Safety Valve Settings

Tag Number

Equipment Protected Process Location Sizing Basis Setting

PSV1-311424A

1st Stage Separator

5-DS-3110A

HP Flare Warm Temperature Collection

Blocked Outlet 93barg

PSV2-31124A

1st Stage Separator

5-DS-3110A



PSV3-31124A

1st Stage Separator

5-DS-3110A



PSV1-311424B

1st Stage Separator

5-DS-3110B



PSV2-31124B

1st Stage Separator

5-DS-3110B



PSV3-31124B

1st Stage Separator

5-DS-3110B



PSV1-31224

Test Separator 5-DS-3120



PSV2-31224




PSV2-31224




PSV1-31205




PSV2-31205



Blocked Outlet 53.6barg

PSV1-32124

2nd Stage Separator 5-DS-3210



PSV2-32124








3.14 Pressure Safety Valve Settings (Cont’d)

Tag Number


PSV1-33106A

Crude Oil Pre-Heater 5-EC-

3310A


Tube Rupture 14barg

PSV2-33106A


3310A


Tube Rupture 14barg

PSV-33104A


3310A


Fire Case 32barg

PSV1-33106B


3310B


Tube Rupture 14barg

PSV2-33106B


3310B


Tube Rupture 14barg

PSV-33104B


3310B


Fire Case 32barg

PSV1-33221

Crude Oil Heaters 5-EC-

3320A/B


Back Flow 16barg

PSV2-33221

Crude Oil Heaters 5-EC-

3320A/B


Back Flow 16barg

PSV1-33206A

Crude Oil Heater 5-EC-

3320A


Tube Rupture 19.4barg

PSV1-33204A


3320A


Fire Case 32barg

PSV1-33206B


3320B


Tube Rupture 19.4barg

PSV1-33204B


3320B


Fire Case 32barg

PSV1-34124

3rd Stage Separator 5-

DS-3410







3.14 Pressure Safety Valve Settings (Cont)

Tag Number


PSV2-34124


DS-3410



PSV3-34124


DS-3410



PSV-36117 Electrostatic Dehydrator 5-DS-3510



PSV1-36124

4th Stage Separator 5-

DS-3610

LP Flare Collection Blocked Outlet 7barg

PSV2-36124


DS-3610

LP Flare Collection Blocked Outlet 7.35barg

PSV3-36124


DS-3610

LP Flare Collection Blocked Outlet 7barg

PSV-37105A

Crude Oil Cooler 5-EC-

3710A


Fire Case 14barg

TSV-37104A


3710A

Crude Oil Cooler 5-EC-3710A Drip Pan

Thermal Expansion

15barg

PSV-37105B


3710B


Fire Case 14barg

TSV-37104B


3710B

Crude Oil Cooler 5-EC-3710B Drip Pan

Thermal Expansion

15barg

PSV-37105C


3710C


Fire Case 14barg

TSV-37104C


3710C

Crude Oil Cooler 5-EC-3710C Drip Pan

Thermal Expansion

15barg





3.15 Valve List

The following table lists all Shutdown Valves (SDV), Emergency Shutdown Valves (ESDV), Emergency Blowdown Valves (EBDV) and Remotely Operated Valves (ROV) in the Oil Production, Stabilisation and Dehydration System.

Tag Number Location

1st Stage Separators 5-DS-3110A and 5-DS-3110B

SDV-31114A/B Crude oil inlets to 1st Stage Separators 5-DS-3110A and 5-DS-3110B

SDV-31116A/B Pressure equalising valves for SDV-31114A/B

SDV-31122A/B Gas outlet to the HP Fuel Gas Scrubber 5-DS-2210


SDV-31117A/B Crude outlet to the 2nd Stage Separator 5-DS-3210

SDV-31120A/B Produced water outlet to the Oily Water Drum 5-DS-4110

SDV-31121A/B Gas outlet to Gas Dehydration Inlet Coolers 5-EC-5510A/B


EBDV-31123A/B Emergency blowdown to the HP Flare

ROV-19002A/B From Methanol Injection Pumps 5-GX-1920A/B



SDV-31214 Crude oil inlet

SDV-31216 Pressure equalising valve for SDV-31214

SDV-31217 Crude outlet to the 2nd Stage Separator 5-DS-3210

SDV-31220 Produced water outlet to the Oily Water Drum 5-DS-4110

SDV-31221 Gas outlet to Gas Dehydration Inlet Coolers 5-EC-5510A/B

SDV-31201 Pressure equalising valves for SDV-31221

EBDV-31223 Emergency blowdown to the HP Flare



ROV1-31201 HP Mode, oil outlet to 2nd Stage Separator 5-DS-3210

ROV2-31201 LP Mode, oil outlet to Crude Oil Pre-Heaters 5-EC-3310A/B

ROV3-31201 HP Mode, gas outlet to Gas Dehydrator Inlet Coolers 5-EC-5510A/B

ROV4-31201 LP Mode, gas outlet to HP Compressor Suction Coolers 5-EC-5310A/B





Valve List (Cont’d)

Tag Number Location


SDV-32117 Crude outlet to the Crude Oil Pre-Heaters 5-EC-3310A/B

SDV-32120 Produced water outlet to Oily Water Drum 5-DS-4110

SDV-32121 Gas outlet to HP Compressor Suction Coolers 5-EC-5310A/B



Crude Oil Pre-Heaters 5-EC-3310A/B

SDV-33114 Condensate return from MP Compressor Scrubber Pumps 5-GX-5230A/B

SDV-33115 Condensate return from LP Compressor Scrubber Pumps 5-GX-5130A/B

Crude Oil Heaters 5-EC-3320A/B

SDV-33215 Hot water inlet

SDV-33216 Hot water outlet

SDV-33218 Crude inlet from Crude Oil Pre-Heaters 5-EC-3310A/B

SDV-33219 Off-spec product line from cargo tanks

3rd Stage Separator 5-DS-3410 and 3rd Stage Separator Pumps 5-GX-3420A/B

SDV-34117 Crude outlet to 3rd Stage Separator Pumps 5-GX-3420A/B

SDV-34120 Produced water outlet to Oily Water Drum 5-DS-4110

SDV-34121 Gas outlet to MP Compressor Suction Cooler 5-EC-5210



SDV-34130 Common pump outlet to Electrostatic Dehydrator 5-DS-3510

Electrostatic Dehydrator 5-DS-3510

SDV-35110 Crude oil outlet line to the 4th Stage Separator 5-DS-3610

SDV-35114 Crude oil inlet line from 3rd Stage Separator Pumps 5-GX-3420A/B

SDV-35115 Water outlet line to Oily Water Drum 5-DS-4110

4th Stage Separator 5-DS-3610

SDV-36117 Crude outlet to Crude Oil Transfer Pumps 5-GX-3720A/B

SDV-36121 Gas outlet to LP Compressor Suction Cooler 5-EC-5110

Crude Oil Coolers 5-EC-3710A/B/C

SDV-37112 From coolers to loading manifold to Crude Storage Tanks

ESDV-37113 From coolers to loading manifold to Crude Storage Tanks





SECTION 4 SAFETY REQUIREMENTS

The Company will strive to prevent injuries and occupational illnesses, and will make all possible efforts to protect the environment through the active participation of employees and contractors.

All personnel arriving on FPSO ‘Akpo’ for the first time shall attend a formal Safety Induction to ensure that they are provided with basic information and knowledge of the Safety Management System prior to starting work.

This section provides health, safety and environmental information relating to operation of the Oil Production, Stabilisation and Dehydration System.





4.1 Health

4.1.1 Personal Protective Equipment

The correct application of Personal Protective Equipment (PPE) is fundamental in securing a safe and healthy place of work for all personnel. PPE shall be used in conjunction with appropriate health, environment and safety procedures that are designed to minimise the potential risk of harm or injury to personnel, while also promoting safe working practices. The correct application of PPE is a requirement of Company policy regarding health, environment and safety.

NOTE For specific PPE requirements, refer to the Permit to Work.





4.2 Safety

Whenever practicable, engineering controls shall be used to reduce and/or eliminate occupational or worksite hazards to personnel. When engineering controls are not available or practicable, residual risks to personnel shall be managed through changes to the work practices and/or operational procedures.

The Company will strive to prevent injuries and occupational illnesses, and will make all possible efforts to protect the environment through the active participation of employees and contractors.

4.2.1 Chemical Hazards

The following hazardous chemicals are used in the Oil Production, Stabilisation and Dehydration System:

• Methanol

• Anti-foam

• Demulsifier

Before handling chemicals and oils, ensure that an adequate risk assessment has been carried out.

Due care must be taken when handling these substances and in any circumstances where it is possible to come into contact with them, for example when taking samples of the produced fluids. Information on the properties of any individual chemical and oil can be found in the chemical datasheets that accompany all materials arriving onboard.

4.2.2 Hazardous Sources

This section identifies potentially hazardous sources associated with the Oil Production, Stabilisation and Dehydration System, and the adverse effects that may result from exposure to them. The hazardous sources, which may be present under upset conditions, are detailed in Table 9.12 – Hazardous Sources.





Table 9.12 – Hazardous Sources

Hazard Source Hazardous Event Effect Control

The Oil Production, System operates at high pressures

Containment failure Potential for personnel injury Vessel rupture Mechanical failure

Care taken when breaking containment

Hydrocarbons under pressure

Sample Points Hydrocarbon release

Potential for ignition

Follow sampling procedures

Hot fluids Oil Production, System operates at high temperatures

Sample Points

Exposure to hot surfaces and/or hot fluids

Potential for personnel injury

Allow time for the equipment to cool down before commencing work

High pressure air Utility stations Compressed air leaking from fitting or hose

Potential for personnel injury

Routine inspections

4.2.3 Nitrogen

To prepare the Oil Production, Stabilisation and Dehydration System for the introduction of hydrocarbon gas, it is necessary to remove all air from the system, using nitrogen from the nitrogen distribution system. Similarly, when preparing equipment for maintenance, nitrogen is used to purge hydrocarbons from the system before breaking containment and introducing air.

WARNING:

Nitrogen is an asphyxiant, and is colourless and odourless: rapid and unrecognised loss of consciousness can occur in persons exposed to a nitrogen-enriched atmosphere. When using nitrogen, care should be taken to ensure that nitrogen escapes are dispersed and not allowed to collect in enclosed areas.





4.3 Environment

4.3.1 Waste Control

The following provides an overview of the methods available to reduce waste and minimise pollution.

All personnel, direct employee or contractor, have responsibilities for environmental protection.

The operation team can help minimise pollution by:

• Maintaining a good preventive maintenance programme that ensures all equipment operates efficiently

• Monitoring exhaust systems for excessive fumes

• Repairing and/or reporting all leaks

• Good housekeeping:

Separation of waste into hazardous or non-hazardous containers

Placing refuse in designated skips

Recycling waste oils





SECTION 5 REFERENCE DOCUMENTS FOR SYSTEM/EQUIPMENT

This section shall comprise a list of associated reference information pertinent to the Section subject matter. It will presented in tabular format, and will include Company, Contractor and Vendor drawings, Vendor Documentation, Cause and Effect Charts, Company documentation (eg Safety Case) etc.

The following documents are available to support the information presented in this Chapter:

Ref Document Number Rev Document Title

09/01 NG50-5-500-PRO-PF-AB-00-0011

00 PFD – Oil Production and Stabilisation (Sheet 1 of 2)

09/02 NG50-5-500-PRO-PF-AB-00-0012

00 PFD – Oil Production and Stabilisation (Sheet 2 of 2)

09/03A NG50-5-500-PRO-PI-AB-31-0001 01 P&ID – 1st Stage Separator Train A

09/03B NG50-5-500-PRO-PI-AB-31-0002 01 P&ID – 1st Stage Separator Train B

09/04 NG50-5-500-PRO-PI-AB-31-0003 01 P&ID – Test Separator

09/05 NG50-5-500-PRO-PI-AB-32-0001 01 P&ID – 2nd Stage Separator

09/06 NG50-5-500-PRO-PI-AB-33-0001 01 P&ID – Crude Oil Pre-Heaters

09/07 NG50-5-500-PRO-PI-AB-33-0002 01 P&ID – Crude Oil Heaters

09/08 NG50-5-500-PRO-PI-AB-34-0001 01 P&ID – 3rd Stage Separator

09/09 NG50-5-500-PRO-PI-AB-35-0001 01 P&ID – Electrostatic Dehydrator

09/10 NG50-5-500-PRO-PI-AB-36-0001 01 P&ID – 4th Stage Separator

09/11 NG50-5-500-PRO-PI-AB-37-0001 01 P&ID – Crude Oil Coolers

09/12 NG50-5-500-PRO-PI-AB-51-0002 01 P&ID – LP Compressor

09/13 NG50-5-500-PRO-PS-AB-00-0052

00 PSD – Oil Production and Stabilisation (Sheet 1 of 2)

09/14 NG50-5-500-PRO-PS-AB-00-0052

00 PSD – Oil Production and Stabilisation (Sheet 2 of 2)

09/15 NG50-5-500-PRO-DS-DS-31-0006

01 PDS – 1st Stage Separators 5-DS-3110A/B

09/16 NG50-5-500-PRO-DS-DS-31-0007

01 PDS – Test Separator 5-DS-3120

09/17 NG50-5-500-PRO-DS-DS-32-0008

00 PDS – 2nd Stage Separator 5-DS-3210





Ref Document Number Document Title

09/18 NG50-5-500-PRO-DS-DS-34-0009

00 PDS – 3rd Stage Separator 5-DS-3410

09/19 NG50-5-500-PRO-DS-DS-35-0010

00 PDS – Electrostatic Dehydrator 5-DS-3510

09/20 NG50-5-500-PRO-DS-DS-36-0011

00 PDS – 4th stage separator 5-DS-3610

09/21 NG50-5-500-PRO-DS-EC-33-0006

01 PDS – Crude Oil Pre-Heaters 5-EC-3310A/B

09/22 NG50-5-500-PRO-DS-EC-33-0007

01 PDS – Crude Oil Heaters 5-EC-3320A/B

09/23 NG50-5-500-PRO-DS-EC-37-0008

00 PDS – Crude Oil Coolers 5-EC-3710A/B/C

09/24 NG50-5-500-PRO-DS-GA-34-0042

00 PDS – 3rd Stage Separator Pumps – 5-GX 3410A/B

09/25 NG50-5-501-VES-CN-DS-31-1010

01 Vendor DS – 1st Stage Separator 5-DS-3110A

09/26 NG50-5-501-VES-DS-DS-31-1012

AA Vendor PDS – 1st Stage Separator 5-DS-3110A

09/27 NG50-5-501-VES-DS-DS-31-1034

AA Vendor PDS – 1st Stage Separator 5-DS-3110B

09/28 NG50-5-501-VES-DS-DS-31-2012

AA Vendor PDS – Test Separator 5-DS-3120

09/29 NG50-5-501-VES-DS-DS-32-0012

AA Vendor PDS – 2nd Stage Separator 5-DS-3210

09/30 NG50-5-501-VES-DS-DS-34-1012

AA Vendor PDS – 3rd Stage Separator 5-DS-3410

09/31 NG50-5-501-VES-DS-DS-36-1012

AA Vendor PDS – 4th Stage Separator 5-DS-3610

09/32 NG50-5-501-VES-CN-DS-35-1026

AA Vendor DS – Electrostatic Dehydrator 5-DS-3510

09/33 NG50-5-501-VES-DS-DS-35-1061

00 Vendor DS – Power Units 5-DS-3510

09/34 NG50-5-501-VES-DS-DS-35-1062

00 Vendor DS – Control Panel 5-DS-3510

09/35 NG50-5-532-ELE-DS-GX-34-0134

01 Vendor DS – Electric Motor 5-GX-3410A/B

09/36 NG50-5-532-ELE-DS-GX-37-0136

01 Vendor DS – Electric Motor 5-GX-3720A/B






09/37 NG50-5-532-MEC-DS-GX-34-0034

BB Vendor DS – Pump 5-GX-3410A/B

09/38 NG50-5-532-MEC-DS-GX-37-0036

BB Vendor DS – Pump 5-GX-3720A/B

09/39 NG50-5-536-VES-DS-EC-37-0510

00 Vendor DS – Crude oil Coolers

5EC-3710A/B/C

09/40 NG50-5-500-PRO-PH-AB-00-0001

01 Process Operating and Control Philosophy

09/41 NG50-5-500-PRO-PH-AB-00-0003

00 Relief and Emergency Depressurisation Philosophy

09/42 NG50-5-500-PRO-PH-AB-00-0005

01 Process Systems Description

09/43 NG50-5-532-OPE-PH-GX-34-0124

01 Control System Description 5-GX-3410A/B

09/44 NG50-5-532-OPE-PH-GX-37-0126

01 Control System Description 5-GX-3720A/B

09/45 NG50-5-536-VES-GN-EC-37-0130

00 Installation Start-up Commissioning Manual 5-EC-3710

09/46 NG50-5-501-VES-SP-DS-31-1030

AA Installation Start-up Commissioning Manual 5-DS-3110A/B

09/47 NG50-5-501-VES-SP-DS-31-2030

AA Installation Start-up Commissioning Manual 5-DS-3120

09/48 NG50-5-501-VES-SP-DS-32-0030


09/49 NG50-5-501-VES-SP-DS-34-1030


09/51 NG50-5-501-VES-SP-DS-35-1048

00 Installation Start-up Commissioning Manual 5-DS-3510

09/52 NG50-5-501-VES-SP-DS-36-1030


09/53 NG50-5-501-VES-SP-DS-31-1031

00 Operation and Maintenance Manual 5-DS-3110A/B

09/54 NG50-5-501-VES-SP-DS-31-2031

00 Operation and Maintenance Manual 5-DS-3120

09/55 NG50-5-501-VES-SP-DS-32-0031







09/56 NG50-5-501-VES-SP-DS-34-1031


09/57 NG50-5-501-VES-SP-DS-35-1049


09/58 NG50-5-501-VES-SP-DS-36-1031


c09 oil production, stabilisation and dehydration

Documents

nd stage separation

approved code

rd stage separation

th stage separation

nd stage separator

company ref

test separation

stage separators