66187933 01 in SITU Combustion Method for Oil Recovery Final

7/25/2019 66187933 01 in SITU Combustion Method for Oil Recovery Final

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IN-SITU COMBUSTION OIL RECOVERY

METHOD

• Submitted By

• Khatri Tousif (28)

• Chaitanya Kulkarni(29)• Maharnab Phukan (30)



IN-SITU COMBUSTION-An EOR process

• It is a Thermal Enhanced oil recovery(EOR) process.

• Also known as the HPAI (High Pressure Air Injection)

• Enhanced Oil Recovery- Additional production of oil

resulting from the introduction of artificial energy into thereservoir.

• Thermal processes -Most common EOR techniques, account

for about 70% production.

• Thermal processes – Input of energy into the reservoirthrough chemical reaction between crude oil and oxygen.

• Reduction of viscosity is primary aim in deploying EOR.



Mechanisms In Thermal Recovery

Process

1. Aim :Viscosity reduction , increasing the mobility of

hydrocarbon.

2. Thermal expansion of the crude oil.

3. Thermal cracking of the crude oil (High heat & temp.to break molecular bonds & reduce molecular weight )

4. Reduction or Elimination of interfacial tension between

the crude oil and water.





What is IN-SITU ?

Involves burning a part of the crude oil in thereservoir to provide the necessary heat .

Enriched-air or oxygen is infused into the reservoircontinuously.

Creating a chemical reaction and release of carbondioxide.

Increased temperature is the driving force behindthe recovery.

This heat reduces viscosity and aiding the flow ofhydrocarbon towards the production well.

The process is initiated by injecting air and acontinuous gas path between injection and

producing ends is established.



Combustion is starts in the formation by injecting air

that is heated to 200 – 650 degrees Celsius

depending upon the oxidation characteristics of the

crude oil.

Water is sometimes injected simultaneously or

alternately with air, creating steam which contributesto better heat utilization and reduced air

requirements.



• High temperatures causes the lighter fractions of oil

ahead of the flame to vaporize , leaving a heavy residual

coke or carbon deposit as fuel.

• The hot produced gases and steam formed by

combustion & vaporization of connate water , move

forward displacing the oil with it.• Until 1979, the In Situ Combustion (ISC) was

commercially applied mainly in heavy oil, non-fractured,

and hydrocarbon reservoirs. However, the widespread

acceptance of an Recovery process came in 1994.





Why In Situ?

• Compressing air is generally cheaper thaninjecting nitrogen or CO2.

• because of mass transfer between the oil and flue

gas or air at reservoir conditions, the lighthydrocarbon components are stripped off the oil.

• We create a very high temperature environmentwhich acts to both crack the oil and mobilize all

the lightest parts of the oil. It leaves behind theless valuable parts—the coke, the heavy carbonas fuel for smoldering.



Various Types of In-Situ Combustion

• Forward

• Reverse

•

In Forward combustion1. Dry

2.Wet

• THAI• CAPRI



• Forward combustion :

ignition occurs near the injection well, and the

hot zone moves in the direction of the air flow

• Reverse combustion :

in reverse combustion, ignition occurs near

the production well, and the heated zone

moves in the direction counter to the air flow.



• THAI and CAPRI Processes

• THAI (Toe-To-Heel Air Injection) and CAPRI (variation ofTHAI with a catalyst for in situ upgrading) are two othervariations of In -Situ combustion.

• Initially, steam is injected to establish communication between the injector and the producer. High temperatures brought on by ignition mobilize the heavy oil/tar sands,which flows from the toe to the heel .

• In CAPRI process, it is proposed that the thermally crackedoil, captured by the horizontal well can be economicallyupgraded to lighter fractions by utilizing a catalytic sheatharound the horizontal well

•

Temp =500-600 degree Celsius• Pressure = 30-40 bar.

• Catalyst = CoMo, alumina











• Pressure: It is important factor for combustion.

• •Temperature: Temperature will affect auto

ignition.(200-650 degree Celsius )

• •Reservoir Thickness: Thickness should be greaterthan about 4m (15 ft) to avoid excessive heat

losses to surrounding formations. Very thickformations may present sweep efficiencyproblems because of gravity override.

• Permeability: This has to be sufficient to allow

injection of air at the designed air flux. The airinjectivity is especially important for heavy oilreservoirs.



• •Oil Gravity: This parameter is not critical. In

situ viscosity has to be low enough to allow air

injection and resulting oil production at thedesign rate.

• •Oil Nature: In heavy oil projects the oil should

be readily oxidizable at reservoir and rockmatrix conditions. This relationship must be

determined by laboratory experiments.. This is

key to the profitability of the process.



Advantages Of IN-SITU

1. Relatively low startup cost, as compare to otherRecovery process.

2. Higher recovery rates.

3. Less water and natural gas used than other recovery

process.

4. Partial upgrading of heavy oil resource . 5. High reservoir pressure where steam is not efficient.

6. In-Situ Combustion has one unique characteristic that itis the only Recovery process which may be applicableover a wide range of crude gravities and viscosities inits most successful form, the process has been applied

in deep, carbonate reservoirs.



Disadvantages of IN-SITU

1. Possible difficulty in controlling fireflood across large

reservoir.

2. Accidents are observed in offshore In-Situ

implementation ( Oil spillage ).

3. The process is not applicable in a thin reservoir,

where there is not enough room to dig two

simultaneous wells .



Recovery Factor1. The Recovery Factor, is the percentage of hydrocarbons

that can be drained from a reservoir, is different for each

field due to the differing geology.

2. It is expected that the continued application of new

technology should allow recovery from oil fields ofover 50% .

3. In recent years, progress in production techniques has

raised the recovery rate of oil & gas.

4. By using In situ combustion method recovery factor

may be increased up to 40-45 %.





Implementation of IN-SITU -

INDIA

1. In India-3 projects , Balol , Santhal & Lanwa part of

ONGC’s Mehsana assets started in 1990.

2. Production capacity exceeding15000 barrels a day(Sept’10)

3. Injecting about 65 mcf a day of air into the 3 reservoirs.

4. Balol & Santhal , oil densities 15-18 degrees API &

viscosity 50-450 centipoise (cp) under reservoir condition.

5. Increased oil recovery factor to 39-45% from 6-12% range.

6. Implemented in North and South kadi in Gujrat.

Source: New Technology Magazine .



Implementation – United States

1. Since 1978, was operated in Williston basin at thecorner of North Dakota , South Dakota & Montana.

2. Encore Acquisition Co. and Continental Resources Inc.

have more than 240 mcf air-injection capacity per day.

3. The oil has more than 30 degrees API gravity.

4. Continental resources – largest In-Situ Combustion

project producing 11500 barrels per day at Cedar Hills

North Unit in Bowman County , North Dacota.



Source :Technical Report EOR/pdf/2010



Reference

• www.wikipedia.com

• www.eia.org

•

www.google.com • New technology magazine/pdf/2010

• www.Indiapetro.com

•EOR

–S. Thomas

http://www.wikipedia.com/

http://www.eia.org/

http://www.google.com/

http://www.indiapetro.com/

http://www.indiapetro.com/

http://www.google.com/

http://www.eia.org/

http://www.wikipedia.com/



THANK YOU

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66187933 01 in SITU Combustion Method for Oil Recovery Final