Produced Water Treatment Project Profile - sawea.org Water... · Produced Water Treatment Project...

Produced Water TreatmentProject Profile

Project Name: Melut Basin Oil DevelopmentProject Name: Melut Basin Oil Development

Client Name: PDOC, Client Name: PDOC, PetroliumPetrolium

EPC: EPC: DodsalDodsal

Consultant: Mott MacDonaldConsultant: Mott MacDonald

Plant Location: Adar/ Agordeed Field Plant Location: Adar/ Agordeed Field

Scope: Scope: Design, Build, and installation Super.Design, Build, and installation Super.

Go Ahead Date: January Go Ahead Date: January -- 20052005

Delivery Date: May Delivery Date: May -- 20052005

Capacity: 1920 M3/dayCapacity: 1920 M3/day

Source of Water: Oil Wells Source of Water: Oil Wells –– Produced WaterProduced Water

Development Oman CompanyDevelopment Oman Company

–– SudanSudan

Sudan Oil Production: 250,000 bbl/d (2004)Sudan Oil Production: 250,000 bbl/d (2004)

Criteria for Awarding the Job

Critical Delivery < 5 MonthsCritical Delivery < 5 Months

Compact DesignCompact Design

Robust and Reliable DesignRobust and Reliable Design

Economic ApproachEconomic Approach

Design Conditions

Inlet Pressure: AtmosphericInlet Pressure: Atmospheric

Outlet Pressure: 1.29 BargOutlet Pressure: 1.29 Barg

Operating Temperature: 55 Deg. C.Operating Temperature: 55 Deg. C.

Design Pressure: 10 BarDesign Pressure: 10 Bar

Design Temperature: 80 Deg. C.Design Temperature: 80 Deg. C.

ANSI Class: 150#ANSI Class: 150#

Water to Oil RatioWater to Oil Ratio

New Well: < 1New Well: < 1

Old Well: > 3 up to 10Old Well: > 3 up to 10

North Sea:North Sea: 70% water, 30% oil70% water, 30% oil

N. America: N. America: 92% water, 8% oil92% water, 8% oil

Main Impurities in Produced WaterDissolved SolidsDissolved SolidsHeavy MetalsHeavy MetalsVarious Oils (emulsified and nonVarious Oils (emulsified and non--emulsified)emulsified)Suspended SolidsSuspended SolidsDissolved Gases (ODissolved Gases (O22, CO, CO22, and H, and H22S)S)Iron ScalesIron ScalesBacteriaBacteriaPhenols, toluene, and other toxic compoundsPhenols, toluene, and other toxic compoundsRust and Corrosion ByproductsRust and Corrosion ByproductsSand GrainsSand GrainsRadioactive ElementsRadioactive ElementsBacteriaBacteriaTreatment ChemicalsTreatment Chemicals

WHAT DO WE REMOVE?Free OilFree OilSand and TurbiditySand and TurbidityDissolved gasesDissolved gasesBacteria and VirusesBacteria and Viruses

WHY?

Reduce harmful emissions to the environmentReduce harmful emissions to the environmentProtect downstream equipment from erosionProtect downstream equipment from erosionPrevent harmful & dangerous gasses from entering Prevent harmful & dangerous gasses from entering the atmospherethe atmosphereImprove well Improve well injectivityinjectivity

Typical Oil Discharge Limits

Location Limit North Sea 40 mg/l

Arabian Gulf 15 to 40 mg/l Gulf of Mexico 29 mg/l

India 48 mg/l Onshore 0-5 mg/l

Sudan 50 mg/l

Raw Water Analysis

Injected Water Quality

Equipment Typically Used inEquipment Typically Used inProduced Water TreatmentProduced Water Treatment

••Surge DrumsSurge Drums

••22--phase separatorsphase separators

••33--phase separatorsphase separators

••Liquid/Liquid HydrocyclonesLiquid/Liquid Hydrocyclones

••Solid/Liquid HydrocyclonesSolid/Liquid Hydrocyclones

••Multiphase Wellhead DesandersMultiphase Wellhead Desanders

••DegassersDegassers

••Single Cell FlotationSingle Cell Flotation

••Induced Gas FlotationInduced Gas Flotation

••Filter Filter Coalescer

••Cartridge FiltersCartridge Filters

••Chemical Injection PackagesChemical Injection Packages

••Gas Pressure LetGas Pressure Let--down Stationsdown Stations

••Hydraulic Wellhead Control Hydraulic Wellhead Control

••Gas FiltersGas Filters

••Packed TowersPacked Towers

••Gas CyclonesGas Cyclones

••Control PanelsControl Panels

••Analyser Houses and LaboratoryAnalyser Houses and Laboratory

Coalescer

PRODUCED WATER DEOILING EQUIPMENT OPTIONSPRODUCED WATER DEOILING EQUIPMENT OPTIONS

Surge TanksSurge Tanks To collect fluids that are subject to regular surge To collect fluids that are subject to regular surge or upset conditionsor upset conditions

Collection VesselsCollection Vessels To collect fluids from multiple sourcesTo collect fluids from multiple sourcesDeoiling HydrocyclonesDeoiling Hydrocyclones Primary Separation for the removal of oil from Primary Separation for the removal of oil from

waterwaterTitled Plate InterceptorsTitled Plate Interceptors Primary separation for the removal of oil from Primary separation for the removal of oil from

waterwaterCentrifugesCentrifuges Primary Separation for the removal of oil from Primary Separation for the removal of oil from

waterwaterDegassersDegassers Removal of gas from water and a final polishing Removal of gas from water and a final polishing

stagestageInduced Gas FlotationInduced Gas Flotation Secondary Separation for the removal of oil from Secondary Separation for the removal of oil from

waterwaterFilter CoalescersFilter Coalescers Removal of oil from waterRemoval of oil from waterDeep Bed Media FiltrationDeep Bed Media Filtration Removal of solids and oil from waterRemoval of solids and oil from waterAdsorption FiltrationAdsorption Filtration Removal of oil from waterRemoval of oil from water

PRODUCED WATER DESANDING EQUIPMENT OPTIONSPRODUCED WATER DESANDING EQUIPMENT OPTIONS

Cyclonic Wellhead Cyclonic Wellhead DesanderDesander

Coarse Sand Removal between 100 to Coarse Sand Removal between 100 to 150 microns150 microns

Coarse StrainerCoarse Strainer All solids removal down to about 80 All solids removal down to about 80 micronsmicrons

Produced Water Produced Water Desanding Desanding HydrocycloneHydrocyclone

Mid range sand removal down to about Mid range sand removal down to about 30 to 40 microns30 to 40 microns

Deep Bed Multi Media Deep Bed Multi Media FiltrationFiltration

Fine Solids removal down to 5 micronsFine Solids removal down to 5 microns

Cartridge FiltersCartridge Filters Coarse to Fine Solids removalCoarse to Fine Solids removal

KEY DESIGN FACTORS:KEY DESIGN FACTORS:

-- Onshore or Offshore?Onshore or Offshore?-- Destination of Produced Water?Destination of Produced Water?-- New Plant, Expansion, Upgrade New Plant, Expansion, Upgrade or Retrofit?or Retrofit?-- Type of Field Type of Field –– Oil or Gas?Oil or Gas?

Process Conditions:Process Conditions:••Flow rate /TurndownFlow rate /Turndown••Pressure/Temperature/ViscosityPressure/Temperature/Viscosity••Composition of Feed StreamComposition of Feed Stream

Main Process Diagram

Main Process Diagram

2 m3/hr20,000 ppm

82 m3/hr500 ppm

80 m3/hr50 ppm

See Through View

Parameters affecting PerformanceParameters affecting Performance

Stokes Low

-- Oil Droplet Size (Shear, Valve location, bends)Oil Droplet Size (Shear, Valve location, bends)-- Pressure Differential Ration (PDR = 1.9)Pressure Differential Ration (PDR = 1.9)

--Example: Feed 7 Bar; Water: 4.5 Bar; Oil: 2 BarExample: Feed 7 Bar; Water: 4.5 Bar; Oil: 2 Bar-- Reject Ratio > 2%Reject Ratio > 2%-- Water lower viscosity at higher temperatureWater lower viscosity at higher temperature-- Oil viscosity: Low viscosity oil can shear easilyOil viscosity: Low viscosity oil can shear easily……-- Specific Gravity Difference.Specific Gravity Difference.-- Cyclone Diameter, Length.Cyclone Diameter, Length.-- Emulsion breakers, coagulants, surface tensionEmulsion breakers, coagulants, surface tension-- Gases up to 10% (Displaces Oil on the overflow)Gases up to 10% (Displaces Oil on the overflow)

Advantages of HydrocyclonesAdvantages of Hydrocyclones

•• High efficiencyHigh efficiency•• compact designcompact design•• Low weightLow weight•• Directly replacementDirectly replacement•• Low CAPEX and low OPEXLow CAPEX and low OPEX•• No moving partsNo moving parts•• Little or no maintenance costsLittle or no maintenance costs•• Reliable and PredictableReliable and Predictable•• Consistently PerformanceConsistently Performance•• Wide material selection Wide material selection

(stainless & duplex steels, (stainless & duplex steels, ceramics, etc) ceramics, etc)

•• Insensitive to motion or Insensitive to motion or orientation

•• Modular (parallel to handle Modular (parallel to handle changes in treating capacities.changes in treating capacities.

•• Portable.Portable.•• Little instrumentation for Little instrumentation for automautom..•• WellWell--understoodunderstood•• Simple to operate, maintain, Simple to operate, maintain,

troubleshoot.troubleshoot.•• No special tools and little No special tools and little

operator training required.operator training required.

orientation

Typical Production FluidsFluids in

Separator =Oil & Water

PW Package Inlet (from Separator)

< 500 ppm

Hydrocyclone Outlet

< 50 ppm

PW Package Outlet

< 30 ppm

Multimedia FiltersMultimedia FiltersSpecial Design FeaturesSpecial Design Features

•• Low Operational Flux (6 to 9 m3/hr/m2 or 2.5 to 3.5 gpm/ft2)Low Operational Flux (6 to 9 m3/hr/m2 or 2.5 to 3.5 gpm/ft2)•• Extended Media Height (1.7 m or 5.5 ft)Extended Media Height (1.7 m or 5.5 ft)•• Special Wedge wire collection systemSpecial Wedge wire collection system•• High Backwash flow rate: 35 m3/hr/m2 on two intervalsHigh Backwash flow rate: 35 m3/hr/m2 on two intervals•• Provision for future air scouringProvision for future air scouring

Multimedia FiltersMultimedia FiltersOperational AspectsOperational Aspects

Multimedia FiltersMultimedia FiltersSequence of OperationSequence of Operation

Unique FeaturesUnique Features

•• Hydraulic simulation calculations.Hydraulic simulation calculations.•• Two skids only to minimize site activities.Two skids only to minimize site activities.•• All skid Interconnecting pipe work, one pipe tie pieceAll skid Interconnecting pipe work, one pipe tie piece•• Compact skid dimension 14.4 x 3.5 metersCompact skid dimension 14.4 x 3.5 meters•• Soft soil Pillars Soft soil Pillars •• SST316 ANSI B73.1 pumps (API mechanical seal fitted with SST316 ANSI B73.1 pumps (API mechanical seal fitted with

plan #62 flushing)plan #62 flushing)•• Dosing systems were preDosing systems were pre--engineered and skid mounted, engineered and skid mounted,

complete with dosing pumps, FRP chemical tanks, mixers complete with dosing pumps, FRP chemical tanks, mixers and corrosion resistant ejectors.and corrosion resistant ejectors.

Extra TreatmentExtra Treatment

Raw Water Tank

Quantity: One (1)Quantity: One (1)

Capacity: 10 m3Capacity: 10 m3

Make: Carbon SteelMake: Carbon Steel

Cyclone Feed Pumps

Quantity: Two (2)Quantity: Two (2)

Capacity: 80 m3/hr at 7 BarCapacity: 80 m3/hr at 7 Bar

Make: Stainless Steel 316Make: Stainless Steel 316

Deoiler - Hydrocyclone

Quantity: One (1) DutyQuantity: One (1) Duty

Capacity: 80 m3/hr at 7 BarCapacity: 80 m3/hr at 7 Bar

Make: Carbon Steel Shell/ SS Make: Carbon Steel Shell/ SS

Duplex LinersDuplex Liners

Feed Oil Level: 450 ppmFeed Oil Level: 450 ppm

Outlet: Less than 20 ppmOutlet: Less than 20 ppm

Multi-Media Filters

Quantity: Three (3) DutyQuantity: Three (3) Duty

Capacity: 80 m3/hrCapacity: 80 m3/hr

Make: C. St. Epoxy CoatedMake: C. St. Epoxy Coated

Diameter: 96Diameter: 96””

Feed TSS: 20 ppmFeed TSS: 20 ppm

Outlet TSS: < 1 ppmOutlet TSS: < 1 ppm

Free CO2 Stripper

Quantity: One (1) DutyQuantity: One (1) Duty

Capacity: 80 m3/hrCapacity: 80 m3/hr

Make: FRPMake: FRP

Diameter: 1.5 X 4 M HDiameter: 1.5 X 4 M H

Feed CO2: 2,400 ppmFeed CO2: 2,400 ppm

Outlet CO2: < 10 ppmOutlet CO2: < 10 ppm

Cartridge Feed Pumps

Quantity: Two (2)Quantity: Two (2)

Capacity: 80 Capacity: 80

m3/hr at 4Bm3/hr at 4B

Make: C.S.Make: C.S.

Micron Cartridge Filters

Quantity: Two (2)Quantity: Two (2)

Capacity: 80 m3/hrCapacity: 80 m3/hr

Make: St. St. 316Make: St. St. 316

Rating: 5 Micron Rating: 5 Micron -- AbsAbs

Chemical Dosing Systems

Quantity: Two (2)Quantity: Two (2)

Type:Type:

BiocideBiocide

O2 ScavengerO2 Scavenger