INTRODUCING OFINTRODUCING OFENHANCED OIL RECOVERYENHANCED OIL RECOVERY

Eng. Rashid Sher Mohd, Eng. Rashid Sher Mohd, M.ScM.Sc

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Lecture ContentsLecture Contents

IntroductionIntroduction

Reservoir Engineering Aspects in IOR and EORReservoir Engineering Aspects in IOR and EOR

Immiscible Flooding (Waterflooding)Immiscible Flooding (Waterflooding)

Miscible FloodingMiscible Flooding

Chemical FloodingChemical Flooding

Thermal InjectionThermal Injection

Microbial Enhanced Oil Recovery (MEOR)Microbial Enhanced Oil Recovery (MEOR)

Guidelines for Selecting IOR and EOR MethodsGuidelines for Selecting IOR and EOR Methods

Design and Implementation of EOR MethodDesign and Implementation of EOR Method

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Lecture EvaluationLecture Evaluation

AttendingAttending = 10 %= 10 %

Home WorksHome Works = 10 %= 10 %

PresentationPresentation = 05 %= 05 %

Mid Test Mid Test = 25 %= 25 %

Final Test Final Test = 50 %= 50 %

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ReferencesReferences

- Latil M, Bardon C, Burger J, Soureau P., “Enhanced Oil Latil M, Bardon C, Burger J, Soureau P., “Enhanced Oil Recovery”, Graham Trotman Ltd, London, 1980.Recovery”, Graham Trotman Ltd, London, 1980.

- Van Poolen,H.K., ”Fundamentals of Enhanced Oil Recovery, Penn Van Poolen,H.K., ”Fundamentals of Enhanced Oil Recovery, Penn Well Books Division of Publishing Company, Tulsa, Oklahoma, Well Books Division of Publishing Company, Tulsa, Oklahoma, 1980.1980.

- National Institute for Petroleum and Energy Research, (NIPER) National Institute for Petroleum and Energy Research, (NIPER) “Enhanced Oil Recovery Information”.“Enhanced Oil Recovery Information”.

INTRODUCTIONINTRODUCTION

Eng. Rashid Sher Mohd, Eng. Rashid Sher Mohd, M.ScM.Sc

HOW IF THE OIL PRODUCTION FROM HOW IF THE OIL PRODUCTION FROM THE WELL OR FIELD WAS DECREASES ? THE WELL OR FIELD WAS DECREASES ?

• A method that use to recover the oil content when A method that use to recover the oil content when the general oil production method no longer the general oil production method no longer efficient efficient

The definition of EORThe definition of EOR

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OIL RECOVERY PHASESOIL RECOVERY PHASES

NATURAL FLOW

WATER DRIVE

DEPLETION DRIVE

GAS CAP DRIVE

GRAVITY DRIVE

COMBI-NATION DRIVE

ARTIFICIAL LIFT

PUMP GAS LIFT

SECONDARYRECOVERY

TERTIARYRECOVERY

WATER FLOODING

IMMISCIBLE GAS FLOOD

PRESSURE MAINTENANCE

FLOODING

MISCIBLE GAS FLOOD

CHEMICAL FLOODING

THERMAL INJECTION

MICROBIALEOR

-CO2 FLOOD- N2 FLOOD- INERT GAS- RICH GAS

- ALKALINE- SURFACTANT

- POLYMER- MICELLAR POLYMER

- ASP

- HOT WATER- STEAM FLOOD

- INSITU COMBUSTION

Primary Recovery

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Natural or Primary Recovery DrivesNatural or Primary Recovery Drives

Solution gas driveSolution gas drive

Gas cap driveGas cap drive

Water driveWater drive

Gravity drainageGravity drainage

Combination driveCombination drive

Gas

Oil

Water

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Secondary RecoverySecondary Recovery

Waterfloods and Immiscible gas Waterfloods and Immiscible gas floodsfloods

No compositional or No compositional or temperature changes take place temperature changes take place in the reservoir in the reservoir except pressure except pressure and displacementand displacement

Suitable for light oil, low Suitable for light oil, low viscosity oil and low pressure viscosity oil and low pressure reservoirsreservoirs

Injector

Producer

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Enhanced Oil RecoveryEnhanced Oil Recovery

Cause physical, chemical, Cause physical, chemical, compositional and thermal compositional and thermal changes in the reservoir rock changes in the reservoir rock and fluidsand fluids

Improve recovery beyond Improve recovery beyond secondary levelsecondary level

Appropriate selection and Appropriate selection and design are importantdesign are important

Injector

Producer

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Typical Recovery FactorsTypical Recovery Factors

Natural or Primary MethodsNatural or Primary Methods

Heavy oil 5 - 15 %Heavy oil 5 - 15 %

Light oil: solution gas drive 10 - 25%Light oil: solution gas drive 10 - 25%

water drive, gas cap 20 - 40%water drive, gas cap 20 - 40%

gravity drainage 30 - 45%gravity drainage 30 - 45%

Secondary MethodsSecondary Methods

Waterflood Waterflood 20 - 45 % 20 - 45 %

Immiscible Gas flood Immiscible Gas flood 15 - 40 % 15 - 40 %

Tertiary or EOR MethodsTertiary or EOR Methods

Laboratory tests Laboratory tests 70 - 90 % 70 - 90 %

Field applications Field applications 45 - 75 % 45 - 75 %

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Incremental Recovery FactorIncremental Recovery Factor

Time or Cum. Production

Qo, BOPD

Extrapolated primary

Primary phase Secondary phase EOR phase

Extrapolated secondary

Incremental Secondary Recovery Incremental

Tertiary / EOR

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ENHANCED OIL RECOVERY (EOR)ENHANCED OIL RECOVERY (EOR)

The main objective of EOR is to recover as The main objective of EOR is to recover as much as possible oil in reservoir / wellmuch as possible oil in reservoir / well

Aim at increasing the oil recovery over its primary Aim at increasing the oil recovery over its primary and secondary potential. and secondary potential.

EOR methods involve injection of substances EOR methods involve injection of substances which cause changes in compositions, which cause changes in compositions, temperature and rock-fluid interactions in the temperature and rock-fluid interactions in the reservoir. reservoir.

In some cases, EOR Methods could be applied In some cases, EOR Methods could be applied after Primary or even at discovery.after Primary or even at discovery.

Sometimes called Tertiary Recovery Methods. This Sometimes called Tertiary Recovery Methods. This does notdoes not mean that EOR Methods have to be mean that EOR Methods have to be applied after Secondary Recovery.applied after Secondary Recovery.

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IOR AND EOR MECHANISMSIOR AND EOR MECHANISMS

ThermalThermal ChemicalChemicalWaterfloodWaterflood Miscible GasMiscible Gas

Maintains reservoir pressure & physically displaces oil with water moving through the reservoir from injector to producer.

Reduces Sorw by steam distillation and reduces oil viscosity.

Reduces Sorw by developing miscibility with the oil through a vaporizing or condensing gas drive process.

Reduces Sorw by lowering water-oil interfacial tension, and increases volumetric sweep efficiency by reducing the water-oil mobility ratio.

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FACTOR AFFECTING EORFACTOR AFFECTING EOR

Reservoir Depth. Reservoir Depth.

Reservoir Heterogeneity. Reservoir Heterogeneity.

Remaining Reserves (RR).Remaining Reserves (RR).

Rock Properties.Rock Properties.

Fluid Properties.Fluid Properties.

Reservoir Drive Mechanisms.Reservoir Drive Mechanisms.

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IOR AND EOR MAIN OBJECTIVESIOR AND EOR MAIN OBJECTIVES

Goal of IOR and EOR processes is to mobilize Goal of IOR and EOR processes is to mobilize remaining oil reserves remaining oil reserves

Achieved by enhancing oil displacement and Achieved by enhancing oil displacement and volumetric sweep efficiencies volumetric sweep efficiencies

- Oil displacement efficiency is improved by reducing oil Oil displacement efficiency is improved by reducing oil viscosity (e.g., thermal floods) or by reducing capillary viscosity (e.g., thermal floods) or by reducing capillary forces or interfacial tension (e.g., miscible floods) forces or interfacial tension (e.g., miscible floods)

- Volumetric sweep efficiency is improved by developing Volumetric sweep efficiency is improved by developing more favorable mobility ratio between injectant and more favorable mobility ratio between injectant and remaining oil reserves (e.g., chemical floods, WAG remaining oil reserves (e.g., chemical floods, WAG processes)processes)

Important to identify remaining oil reserves and Important to identify remaining oil reserves and mechanisms necessary to improve recovery before mechanisms necessary to improve recovery before implementing IOR and EOR implementing IOR and EOR

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EOR IMPLEMENTATION STEPSEOR IMPLEMENTATION STEPS

GEOLOGYDATA

RESERVOIRDATA

PRODUCTION DATA

RESERVOIR

Type of RockMigration DirectionBulk Volume (Vb)

Rock Properties Fluid Properties Reservoir Condition Reservoir Drive

Mechanism

Oil CutWater CutRemaining Reserve

Screening Criteria

Selecting EOR Methods

Laboratory Study

Simulation Study

Pilot ProjectFull Scale

PorosityPermeabilitySaturationWettabilityCapillary Pressure

Oil PropertiesWater Properties

Res. PressureRes. Temperature

Evaluation

Monitoring and Evaluation