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Shell Nigeria Exploration and Production Company Ltd.

Bonga FPSO Plant Operating Procedures Manual Volume 11 PRODUCED WATER TREATMENT SYSTEMS

OPRM-2003-0311 Version: 1.2

This document is not confidential. The Copyright of this document is vested in Shell Nigeria Exploration and Production Company Limited. All rights reserved. Neither the whole nor any part of this document may be reproduced, stored in any retrieval system or transmitted in any form or by any means (electronic, mechanical, reprographic, recording or otherwise) without the prior written consent of the copyright owner.

Shell Nigeria E & P Company Ltd.

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Document Status Information 1.0. DOCUMENT CONTROL 1.1. Change History Date

Version

Author

Ref Indicator

01/03/04

1.0

ODL

–

Issue of document for signature.

31/08/05

1.1

ODL

–

Amendments to:

Change Description

• Preliminary Pages • Part 1 Section 2 Paragraphs 3.4.2 and 4.0 Part 2 Section 1: • Procedure No 1/001 removed • Pre-start Checks Steps 1 and 5 altered and addition to Step 2 • Cold Start-up Steps 2 and 3 removed. Steps 6, 7, 10 and 16 altered, Step 11 added. • Procedure No 1/005 ERS 2 altered Part 2 Section 3 Hydrocyclone Backflushing Procedure No 3/002 title ‘ Manual Backwash’ added and Automated Backwash Steps 1 to 9 added. 30/04/06

1.2

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ODL/SNEPCO

–

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Amendments throughout to address outstanding HOLDs and to reflect the final asbuilt P&IDs.

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PURPOSE The purpose of this document is to provide guidance on the safe, efficient and environmentally aware operation of the Produced Water Treatment Systems. It is one Volume within an overall suite of Volumes which comprise the Bonga FPSO Plant Operating Procedures Manual (POPM). The full listing of Volumes is as follows: Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume Volume

1 2A 2B 2C 2D 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35

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Field and Facilities Overview Subsea Production System Subsea Waterflood System Subsea Control System Flow Assurance Guidelines Oil Separation and Treatment Oil Storage, Handling and Ballast Systems Oil Metering and Export System Vapour Recovery Compression System Field Gas Compression System Gas Dehydration/Glycol Regeneration Systems Gas Export/Import/Lift Systems Flare and Vent Systems Produced Water Treatment Systems Waterflood System Chemical Injection and Methanol Injection System Fuel Gas System Heating Medium System Drainage Systems Sewage Treatment Systems Bilge and Oily Water Separation Systems Inert Gas System Nitrogen Generation System Seawater System Fresh and Potable Water Systems Diesel Fuel System and Incinerator Aviation Fuel System Instrument and Utility Air System Deck Hydraulic Systems Fire Protection Systems and Equipment Safety and Lifesaving Equipment PSCS and ESS Power Generation and Distribution Systems Black Start Procedures HVAC Systems Deck Machinery and Mechanical Handling Systems (Cranes, etc) Telecommunications Ancillary Living Quarters (ALQ)

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SCOPE This document provides a detailed description of the plant and equipment which comprise the Produced Water Treatment Systems and includes stepby-step guidance on the operation of the system and its equipment, under both normal and abnormal operation.

4.0

TARGET READERSHIP All SNEPCO staff, contractors and other third-party personnel who may be involved in the operation of the Produced Water Treatment Systems onboard the Bonga FPSO.

5.0

SPECIAL NOTE Not applicable.

6.0

ABBREVIATIONS The abbreviations used within this document are listed at the end of these introductory pages.

7.0

REFERENCE INFORMATION/SUPPORTING DOCUMENTATION The primary reference/supporting documents, which have been either used or referred to in the development of this document, are listed at the end of these introductory pages. These are part of the available Operational Documentation, which SNEPCO Offshore Operations (OO) has in place to support its day-to-day operations. These and many other documents are available within the SNEPCO Livelink System. Where appropriate, these documents have been cross-referenced within this document.

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Abbreviations AC ACB AEP ANSI API

Alternating Current Air Circuit-breaker Authorised Electrical Person American National Standards Institute American Petroleum Institute

BA bara barg BASEEFA BBL BOPD BPD BS&W BWPD

Breathing Apparatus Bar Absolute Bar Gauge British Approvals Service for Electrical Equipment in Flammable Atmospheres Barrel Barrel of Oil per Day Barrels per Day Base Sediment and Water Barrel of Water per Day

CCR CEP CI CT CIV CV

Central Control Room Competent Electrical Person Chemical Injection Current Transformer Chemical Injection Valve Production Choke Valve

DC DCS DE DO DPR

Direct Current Distributed Control System Drive End Digital Output Department of Petroleum Resources

ECP ESR 1 ESR 2 ESR 3 ESS

Engine Control Panel Process Shutdown Surface Process Shutdown Total FPSO Shutdown Emergency Support System

F&G FBHP FC FCV FG FIC FLA

Fire and Gas Flowing Bottomhole Pressure Fail Closed Valve Flow Control Valve Flow Indicating Gauge Flow Indicating Controller First Line Ashore

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FO FPSO FS FT FTP FZA

Fail Open Valve Floating Production, Storage and Offloading Fuse Switch Flow Transmitter Flowing Tubing Pressure Flow Safety Alarm

GA GOR GT

General Alarm Gas/Oil Ratio Gas Turbine

H HH HCU HCV HMI HOV HP HPI HPU HSE HV HVAC Hz

High Alarm High Trip Hydraulic Control Unit Hand Control Valve Human Machine Interface Hand Operated Valve High Pressure High Performance Insulation Hydraulic Power Unit Health, Safety and Environment High Voltage Heating, Ventilation and Air Conditioning Hertz (Frequency)

ID IGF IGG IGV IP IS ISO

Internal Diameter Induced Gas Flotation Inert Gas Generator Inlet Guide Vane Intermediate Pressure Intrinsically Safe International Standards Organisation

kW

Kilowatt

L LAT LC LCV LEL LG LIC LL LO LOS LP

Low Alarm Lowest Astronomical Tide Locked Closed Level Control Valve Lower Explosive Limit Level Gauge Level Indicating Controller Low Trip Locked Open Line of Sight Low Pressure

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LPG LS LSA LSA LT LV LZA

Liquified Petroleum Gas Level Switch Load-shed Application Low Specific Activity (Scale) Level Transmitter Low Voltage Level Safety Alarm

MOV m/s MSDS MW m3 MAC MCC MCCB MEG MGPS MIS MIV MMSCFD

Motor Operated Valve Metre per Second Material Safety Datasheets Megawatt Cubic Metres Manual Alarm Callpoint Motor Control Centre Moulded Case Circuit-breaker Mono Ethylene Glycol Marine Growth Prevention System Management Information System Methanol Injection Valve Millions of Standard Cubic Feet per Day

NB NC NDE NDT NGL NO NPSHA NRV

Nominal Bore Normally Closed Non-drive End Non-destructive Testing Natural Gas Liquid Normally Open Net Positive Suction Head Available Non-return Valve

O/A/S OD OID OLI

Off/Auto/Start Outside Diameter Operator Interface Display On-line Inspection

P&ID PCF PCV PDR PDS PDT PFD PFS PG PIC

Piping and Instrument Diagram Permit Control Facility Pressure Control Valve Pressure Difference Ratio Differential Pressure Switch Differential Pressure Transmitter Process Flow Diagram Programming Functional Specification Pressure Gauge Pressure Indicator Controller

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PIV PM PMV PPE ppm v/v ppm wt/wt PSCS PSD PT PTW PZA

Pigging Isolation Valve Production Manifold Production Master Valve Personnel Protective Equipment Part per Million by Volume Parts per Million by Weight Process Safety and Control System Process Shutdown Pressure Transmitter Permit to Work Pressure Safety Alarm

RV RVP RTJ

Relief Valve Reid Vapour Pressure Ring Type Joint

SCSSV SCU SDV SI SI Sm3/hr SPM SRB SSDS SWL SWP SWV

Surface Controlled Subsea Safety Valve Subsea Control Unit Shutdown Valve Statutory Instrument Switchgear and Instrumentation Standard Cubic Metres per Hour Single Point Mooring Sulphate-reducing Bacteria Safety Shutdown System Safe Working Load Safe Working Pressure Sacrificial Wing Valve

TCV TDS TEG TG TIC T/T TT TVP TZA

Temperature Control Valve Total Dissolved Solids Tri-ethylene Glycol Temperature Gauge Temperature Indicating Controller Tangent to Tangent (Vessel Length) Temperature Transmitter True Vapour Pressure Temperature Safety Alarm

UCP UEL UF UPS USD UV

Unit Control Panel Upper Explosive Limit Under-frequency Uninterruptible Power Supply Unit Shutdown Ultraviolet

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VCB VDC VDU VFC VFD VRU VT

Voltage Circuit-breaker Video Display Computer Visual Display Unit Vacuum Fused Contactor Variable Frequency Drive Vapour Recovery Unit Voltage Transformer

WHRU WI WI WSV

Waste Heat Recovery Unit Water Injection WOBBE Index Well Switching Valve

XOV

Crossover Valve

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Reference Information/Supporting Documentation Project Data Document No/Ref

Document Title

BON-AME-3PP-B-01043-001A01

Operator Guide Produced Water System (System 43)

BON-AME-3PP-B-21423-002C06

P&ID LP Separator

BON-AME-3PP-B-21423-003C06

P&ID LP Separator

BON-AME-3PP-B-21423-007C06

P&ID Bulk Oil Treater

BON-AME-3PP-B-21443-001C06

P&ID Produced Water Tank and Pumps

BON-AME-3PP-B-21443-002C06

P&ID Hydrocyclone

BON-AME-3PP-B-21443-003C06

P&ID Induced Gas Flotation Separator

BON-AME-3PP-B-21448-001C06

P&ID Closed Drain and Overboard Header

BON-AME-3GN-B-25082-012A01 Sheet 1 of 1

Cause and Effect Diagram Produced Water System (System 43)

BON-AME-3GN-B-25082-004C02 Sheet 1 of 1

Cause and Effect Diagram LP Production System (System 23)

Vendor Data Vendor

Document Number

Document Title

Baker Process Production and Refining

P237-H-002 Volume 1 of 1

Technical Maintenance Manual for Induced Gas Flotation Vessel

Baker Process Production and Refining

P237-H-004 Volume 1 of 1

Technical Maintenance Manual for De-oiling Hydrocyclone

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Sulzer Pumps

P0001/29/M008/00 1 Sulz-088-340

Technical Manual (Installation, Operation and Maintenance)

Baker Process Production and Refining

P237-M-500 Volume 1 of 1

Datasheets for the Hydrocyclone Vessel S-4340

Baker Process Production and Refining

P237-M-501 Volume 1 of 1

Datasheets for the IGF Separator V-4341

HEMP Actions No

Description

Control Measure

ODL Action

1

Valve alignment of produced water out of the LP Separators, incorrect listing of valves.

Update POPM with correct valve alignment and valve numbering, ensure latest available revision of the documentation is available prior to writing of POPM.

Procedure No 1/001 Cold Start-up Valve table amended.

2

Priming and starting of produced water pumps – confusion due to statement of cracking open suction SDV and starting of pump with closed discharge valve. Could pre-filling of piping be a better option?

Input more information to the POPM concerning type of pump and specific start-up sequence.

Procedure Nos 1/001 and 1/002 amended.

The discharge valve is a CSO valve. 3

Charging of the system with seawater prior to start-up, POPM is vague as to the management of the operation.

Specific description of the operation to be detailed in the POPM.

Added to prestart checks in Procedure No 1/001.

4

Start-up of oil-in-water analysis is not specific as to when system should be placed in operation.

More detail required in the procedures.

Amended in Procedure Nos 1/001 and 1/002.

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HAZOP Actions Action Number/ Node

Node Description

Response to HAZOP

290/6.0 3

Produced Water Hydrocyclones

Carry out routine back-flushing once per shift.

Part 2 Section 3 Procedure No 3/002.

130/17

Induced Gas Flotation Separator

Methanol from production process passing overboard with the produced water.

Text and references added to Part 1 Section 1 Paragraph 3.3.

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Operation Procedure Section/Procedure

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Main Table of Contents

Document Status Information Abbreviations Reference Information/Supporting Documentation Part 1 – Technical Description Section 1

System Overview

Section 2

Detailed Description

Part 2 – Operating Procedures Section 1

System Operating Procedures

Section 2

Equipment Operating Procedures

Section 3

Supplementary Operating Procedures

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PART 1 TECHNICAL DESCRIPTION Section 1

System Overview

Section 2

Detailed Description

Part 1 Technical Description

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Part 1 Technical Description Section 1 System Overview

Table of Contents 1.0

INTRODUCTION............................................................................................................. 2

2.0

PROCESS DESCRIPTION ............................................................................................. 2

3.0

HEALTH, SAFETY AND ENVIRONMENT (HSE) .......................................................... 3 3.1

General................................................................................................................ 3

3.2

Specific Hazards.................................................................................................. 4

3.3

Environmental Issues .......................................................................................... 4

FIGURES Figure 1.1 – Produced Water System Overview ...................................................................... 6

Part 1 Section 1 System Overview

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INTRODUCTION All produced water extracted from the Bonga well fluids by the Oil Separation and Treatment System is processed by the Produced Water Treatment System. The produced water treatment facilities ensure the quality of the water discharged to sea meets the required standard of 15ppm (wt) from a maximum inlet hydrocarbon concentration of 1000ppmv. The Produced Water Treatment System consists of the following major components: •

Produced Water Tank V-4340

•

Produced Water Pumps P-4340A/B

•

Produced Water Hydrocyclone S-4340

•

Induced Gas Flotation (IGF) Separator V-4341

The system is currently rated to process 100,000BWPD of produced water but is designed to accommodate future expansion of up to 160,000BWPD.

2.0

PROCESS DESCRIPTION Refer to Figure 1.1. The produced water leaving the Oil Separation and Treatment System contains too high a concentration of oil for dumping at sea, and is therefore treated by passing the fluid through the Produced Water Treatment System. Produced water separated in the LP Separators V-2341A/B and Bulk Oil Treater V-2343 enters the Produced Water Tank V-4340 under the interface level control of these vessels. The combined incoming flow passes into a 20in inlet manifold and mixes with any clean produced water recycled from the hydrocyclone. Dosing points for the injection of water clarifier and scale inhibitors are located on the produced water outlets from the LP separators. Produced Water Tank V-4340 is a vertical, two-phase vessel designed to remove dissolved hydrocarbon gases from the incoming produced water. The vapours are released to the first-stage VRU suction scrubber. The produced water tank operates at low pressure to maximise hydrocarbon vapour recovery to the VRU compressor. Degassed produced water is passed from the tank to the suction of the 100% capacity Produced Water Pumps P-4340A/B. The duty pump discharges the produced water to Hydrocyclone S-4340. The produced water pumps are specifically designed to limit the shearing effect on any oil droplets in the produced water, so as not to adversely affect the oil removal efficiency in the hydrocyclone. The produced water pumps are protected against operating below the minimum flowrate by a recycle line. When the discharge flow falls below the minimum set point, a recycle flow control valve opens to recycle water from the pump discharge back to the produced water pump. There is provision to install a third produced water pump (P-4340C) at a later date when the water cut of the Bonga reservoir fluids has increased to a point where the existing capacity of the Produced Water Treatment System is exceeded. Produced Water Hydrocyclone S-4340 consists of a single hydrocyclone unit, which contains a number of individual hydrocyclone tubes (normally referred to as hydrocyclone liners).

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There is provision to install a second produced water hydrocyclone (S-4341) to process the extra produced water in the future. In the hydrocyclone unit the oil droplets suspended in the produced water are separated from the water by enhanced gravity separation and leave the hydrocyclone through three individual oil reject lines to a common oil reject header for re-processing in the production sump. The denser water phase exits the hydrocyclone at about 40ppm (wt) and discharges into a clean water outlet header. Clean water from the hydrocyclone is directed to Induced Gas Flotation Separator V-4341, which further reduces the oil-in-water concentration until it is within the required specification of 15ppm (wt) total. A chemical injection point is provided on the clean water outlet from the hydrocyclone so as to enable water clarifier to be injected to the induced gas flotation separator, if required. The addition of this chemical encourages bonding of the small oil droplets to enhance the performance of the IGF separator. The induced gas within the IGF separator assists the upward velocity of the oil droplets to float to the surface as a foam, where they are skimmed off and directed to the production sump. Hydrocarbon gas is vented from the IGF separator to the first-stage VRU suction scrubber. Clean, degassed produced water is discharged to the sea from the IGF separator, under level control. An oil-in-water analyser is provided for monitoring the produced water being dumped overboard. This is located on the downstream pipework of the IGF separator and will alarm to indicate a high level of oil-in-water content. Final disposal of the produced water takes place through the overboard header and caisson to the sea. Off-spec produced water which cannot be dumped to sea is switched to the slop oil tank or the primary reception tank.

3.0

HEALTH, SAFETY AND ENVIRONMENT (HSE)

3.1

General The Produced Water Treatment System is located on the vessel topsides and as such forms part of the main topside operating area. All personnel in the area must have received training in, and be fully conversant with, the following: •

Location and use of fire and safety equipment in the area

•

Recognition and response to all the vessel’s visual and audible alarms

•

Muster and evacuation procedures

•

Escape routes

•

Location and use of lifesaving equipment

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Specific Hazards The Produced Water Treatment System handles mainly produced water at relatively low temperature (50°C) and pressure. Therefore, hazards are low compared with other processing systems. However, it is incorrect to assume that no hazards exist. Potential hazards include the following: •

The produced water tank is gas blanketed

•

Level control problems in the LP separators or oil treater could result in large quantities of oil reaching the produced water tank

•

Level control problems in the LP separators could result in gas blowby, with large volumes of gas flowing to the produced water tank

This system cannot be taken for granted just because it usually contains mostly water. All personnel must wear the appropriate protective clothing (overalls, safety helmet, gloves, goggles etc) when in the area, and wear hearing protection if noise levels in the area are high. The Produced Water Treatment System employs various items of rotating equipment which must have all moving parts securely guarded at all times.

3.3

Environmental Issues

3.3.1

Overboard Discharge Since the Produced Water System discharges effluent overboard, environmental issues could arise if the discharge fails to meet the required discharge parameters. However, the final effluent is automatically monitored and if its quality deteriorates below the allowable value, the off-specification water is automatically diverted for further treatment. Diverted water will usually be routed to the dirty slops tank. From there it will be pumped to the LP separator for reprocessing. Refer to Volume 2 Subsea Facilities, Flowlines and Risers for details.

3.3.2

Low Specific Activity (LSA) Naturally Occurring Radioactive Material (NORM) is found throughout the natural environment, including reservoir formations. Formation water (ie produced water) dissolves radioactive salts from the formation rock and brings NORM to the surface with the produced water. The activity concentration of this NORM contamination is very low, and to emphasise that the concentrations are very low, such material is usually referred to as LSA. Since the levels are typically very low, LSA in produced water is not a problem, unless it becomes concentrated in some manner. As the produced water is subjected to changes in temperature and pressure during the treatment process, dissolved solids may precipitate out of solution and deposit scale and sediment (sludge). Sludge and scale wastes should be removed from production equipment in a safe and controlled manner, and disposed of in a manner that complies with local regulations.

Part 1 Section 1 System Overview

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Methanol in Produced Water Methanol injected at the crude oil wells, flowlines and topsides process facilities appears in the produced water. Methanol biodegrades in water, however methanol in high concentrations (>1%) in fresh or salt water can have harmful effects on aquatic flora and fauna within the immediate discharge area. Under current environmental guidelines and standards for the Petroleum Industry in Nigeria (revised edition 2002) issued by the Department of Petroleum Resources (DPR), methanol discharge from offshore structures is currently unregulated. However, in line with best practice, methanol discharge from Bonga should be kept as low as reasonably practicable.

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Figure 1.1 – Produced Water System Overview

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Part 1 Technical Description Section 2 Detailed Description

Table of Contents 1.0

INTRODUCTION............................................................................................................. 2

2.0

EQUIPMENT DETAILS .................................................................................................. 2

3.0

2.1

Produced Water Tank.......................................................................................... 2

2.2

Produced Water Pumps ...................................................................................... 3

2.3

Produced Water Hydrocyclone............................................................................ 4

2.4

Induced Gas Flotation Separator......................................................................... 6

CONTROL AND INSTRUMENTATION.......................................................................... 7 3.1

Produced Water Tank V-4340 ............................................................................. 7

3.2

Produced Water Pumps P-4340A/B .................................................................... 8

3.3

Produced Water Hydrocyclone S-4340 ............................................................... 9

3.4

Induced Gas Flotation Separator S-4341 .......................................................... 11

3.5

Overboard Discharge Water Quality.................................................................. 13

4.0

MODES OF OPERATION............................................................................................. 14

5.0

SAFEGUARDING ......................................................................................................... 14

TABLES Table 2.1 – Produced Water Tank Controllers, Alarms and Trips............................................ 8 Table 2.2 – Produced Water Pumps Controllers, Alarms and Trips......................................... 9 Table 2.3 – Induced Gas Flotation Separator Controllers, Alarms and Trips......................... 13 Table 2.4 – Produced Water System Relief Valve Settings ................................................... 15 FIGURES Figure 2.1 – Produced Water Tank and Pumping Facilities ................................................... 16 Figure 2.2 – Produced Water Hydrocyclone ......................................................................... 17 Figure 2.3 – Induced Gas Flotation Separator ....................................................................... 18

Part 1 Section 2 Detailed Description

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INTRODUCTION The Produced Water Treatment System removes the traces of oil from the water which has been produced with the crude oil from the Bonga formation and undergone separation in the LP separators and bulk oil treater. After treatment, the clean water is discharged overboard. Major items in the Produced Water Treatment System are as follows: •

Produced Water Tank V-4340

•

Produced Water Pumps P-4340A/B

•

Produced Water Hydrocyclone S-4340

•

Induced Gas Flotation (IGF) Separator V-4341

2.0

EQUIPMENT DETAILS

2.1

Produced Water Tank Equipment Details Tag Number:

V-4340

Location:

Port Process Module

Manufacturer:

IMS

Design:

Welded steel with vertical support

Design Temperature:

-10°C to 94°C

Design Pressure:

+1.034barg/-0.052barg

Capacity:

729.0m3/hr

Refer to Figure 2.1 or P&ID BON-AME-3PP-B-21443-001-C066. Equipment Description The purpose of Produced Water Tank V-4340 is to collect produced water from the LP separators and bulk oil treater operating at pressures ranging from 20.0barg to 2.4barg, and to provide safe disposal to the first-stage VRU suction scrubber of gases liberated by the pressure reduction in the vessel to 0.5barg. Because the produced water tank is fed with produced water by process vessels at different pressures, emulsification and oil droplet dispersion may occur in the vessel. Consequently, the size of the next downstream vessel, Induced Gas Flotation Separator V-4341, has been designed to give a long residence time to aid the break-up of emulsions. Produced Water Tank V-4340 is a vertically mounted vessel which measures 5.486m in diameter and 5.586m in height (tan/tan). The internal surfaces of the tank are epoxy lined to avoid corrosion. The tank has a design pressure of +1.034/-0.052barg, a temperature range of -10 to +94°C and is sized for the future produced water flowrate of 160,000BWPD.

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Produced water enters at the top of the tank through a 20in flanged nozzle. The fluid is directed through an internal drop line to the bottom of the tank where it is distributed through a series of 25mm x 230mm slots to minimise splatter. This process, together with the drop in pressure, encourages dissolved hydrocarbon gases to flash-off. Under normal operating conditions the pressure in the produced water tank is not allowed to exceed 0.5barg, with make-up gas directed through 32-PCV-001 to the tank as necessary. Vacuum Breaker 43-PSV-303, which is set at -26mbarg provides protection against vacuum conditions. The produced water tank is designed to counteract the adverse effects of FPSO motion, and operates as a two-phase separation vessel approximately half liquid full, with 4 minutes hold-up time between high and low alarm points. Any separated oil droplets float on top of the water and form a layer over a period of time. Provision is made to drain off or ‘skim’ any such accumulations of oil in the vessel by means of 10 individual valved tappings over the operating range of the vessel with 6in spacing. The tappings are arranged in two groups of five each with a manifold, leading to two tundishes. Skimmed oil is disposed of from each tundish to the Collection Sump S-4701B. Level Gauges 43-LG-302A and B allow constant monitoring of the level inside the tank. An overflow line is hard piped from the produced water tank to the dirty slops tank. Degassed produced water flows through a vortex breaker from the tank to the Produced Water Pumps P-4340A/B.

2.2

Produced Water Pumps Equipment Details Tag Number:

P-4340A/B

Location:

Port Process Module

Manufacturer:

Sulzer Pumps

Model:

VCR 10-14-24A/6 Stage

Driver Rating:

350kW

Voltage:

6.6kV

Suction Pressure:

0.5barg

Discharge Pressure:

12.1barg

Capacity:

662.5m3/hr

Refer to Figure 2.1 or P&ID BON-AME-3PP-B-21443-001-C064.

Part 1 Section 2 Detailed Description

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Equipment Description The produced water pumps are required to raise the pressure of the degassed produced water from Produced Water Tank V-4340 up to 12barg. This is the required pressure to drive the fluids through the hydrocyclone. There are two identical pump sets provided, one dedicated for duty and the other as standby. The manufacturer of the pump sets is Sulzer Pumps. The produced water pumps are low speed, low sheer, vertical canister pumps, which are specifically designed to limit the shearing effect on any oil droplets in the produced water, so as not to adversely affect the oil removal efficiency in the downstream hydrocyclone. A removable strainer is provided on the produced water pump suction to protect the pump from debris. The pump has six stages and is driven through a Kopflex, disc type, spacer coupling by a 350kW electric motor. The pump bowl is supported by the discharge column, which also houses the line shaft drive to the impellers. At the top of the discharge column is the suction and discharge head, which allows connection of the lines to and from the pump. The suction connection directs produced water into the canister from where the pump draws the fluid. Draining of the suction can and pump casing is achieved by pressurising the suction can with nitrogen. The electric motor driver is mounted vertically upon the suction and discharge head. Produced water leaves the discharge column through an elbow to the discharge nozzle. The line shaft penetrates the elbow to connect to the driver, with containment provided by a John Crane single-cartridge mechanical seal. Each produced water pump has a capacity of 662.5m3/hr (100,000BWPD). Produced water exits the discharge of the duty pump and is directed to Produced Water Hydrocyclone S-4340. The duty pump operates continuously at a constant throughput with Flow Control Valve 43-FCV-321 regulating the discharge flow through a recycle line, from downstream of the hydrocyclone, back to the inlet header for the produced water tank.

2.3

Produced Water Hydrocyclone Equipment Details Tag Number:

S-4340

Location:

Port Process Module

Manufacturer:

Baker Process Production and Refining

Model:

M1150-Km-300#

Operating Weight:

7710kg

Design Temperature:

-10°C to 94°C

Design Pressure:

24.1barg

Inlet Oil Concentration:

1000ppm

Outlet Oil Concentration: