Adjusted Brine Chemistry

(Designer Waterfloods)Geoffrey Thyne

Mao Romero

Pubudu Gamage

Haifeng Jiang

Matt JohnsonEnhanced Oil Recovery Institute

E N H A N C E D O I L R E C O V E R Y I N S T I T U T E

The fundamental objective is to change

wettability in the reservoir to increase oil

recovery by changing the injected water

chemistry.

Adjusted Brine Chemistry (ABC)

E N H A N C E D O I L R E C O V E R Y I N S T I T U T E

Proposed Adjusted Brine Chemistry for

Carbonates

• Carbonate rocks are oil-wet with low recovery.

• Positively-charged carbonate surface attracts negatively–charged carboxylic acid anions in oil

promoting oil-wet surfaces.

• Addition of sulfate ions (SO42-) can change

wetting and make surface more water-wet.

• Inexpensive and easy to implement.

E N H A N C E D O I L R E C O V E R Y I N S T I T U T E

Designer Waterfloods

(Smart Water)

• Høgnesen et al., 2005, SPE 94166.

• Zhang et al., 2007, Colloids and Surfaces A: Physiochem. Eng.

Aspects 301, 199-208.

• Strand et al., 2008, Energy and Fuels 22, 3222-3225.

• Puntervold and Austad, 2008, Journal of Petroleum Science and

Engineering 63, 23-33.

• Puntervold et al., 2009, Energy and Fuels 23, 2527-2536.

• RezaeiDoust et al., 2009, Energy Fuels 23, 4479-4485.

• Alotaibi et al., 2010 SPE 129972.

• Fathi et al., 2010, Energy Fuels 24, 2974-2979.

Proposed Adjusted Brine Chemistry for

Carbonates

+ Carbonate Surface

+

S

O-

O

O-

O

O-

O

Oil

C

Proposed Adjusted Brine Chemistry for

Carbonates

+ Carbonate Surface

+

S

O-

O

O-

OO-

O

Oil

C

E N H A N C E D O I L R E C O V E R Y I N S T I T U T E

Adjusted Brine Chemistry

• Carbonate reservoirs recovery is normally 10-

30% OOIP.

• Injection of seawater into chalk reservoirs in the

North Sea has doubled recovery factors.

• Process has been extended to limestone, but

not dolomite.

E N H A N C E D O I L R E C O V E R Y I N S T I T U T E

Target Carbonate Formations

Prod Zone Name

Sum of Oil

Cum

Sum of Gas

Cum

Sum of Wtr

Cum

BBLS MCF BBLS

MADISON 477,789,462 6,029,426,158 6,591,240,789

EMBAR 344,900,918 172,251,426 3,429,183,519

PHOSPHORIA 259,456,919 332,502,221 1,731,066,310

NIOBRARA 13,598,344 10,637,033 5,791,752

E N H A N C E D O I L R E C O V E R Y I N S T I T U T E

Madison Fields in Wyoming

E N H A N C E D O I L R E C O V E R Y I N S T I T U T E

Top Ten Madison Producers in 2010

Field Reservoir Wells Oil BBL Gas MCF Water BBL. Gravity

BEAVER CREEK MADISON 17 1,024,776 4,665,485 8,264,000 41

GARLAND MADISON 171 679,245 279,882 84,850,496 21

LOST SOLDIER MADISON 24 385,218 9,583,815 5,943,463 32

ELK BASIN MADISON 75 365,836 197,832 31,099,049 29

OREGON BASIN MADISON 47 327,336 173,752 40,389,320 20

WERTZ

DARWIN-

MADISON 19 205,918 8,421,265 10,675,124 32

WHITNEY

CANYON-

CARTER CREEK MADISON 26 103,671 14,336,877 65,489 42

TORCHLIGHT MADISON 21 42,238 0 5,444,032 23

HAMILTON DOME MADISON 12 29,916 0 3,378,334 18

SPENCE DOME MADISON 61 16,939 0 4,107,366 19

3,181,093

WYOGCC Field by Reservoir with Gravity

Field

testing

Field

scale

models

Lab

tests

Screening

Improved

Recovery

Enhanced Oil Recovery Institute

Program

Components

• Screening of fields

• Laboratory evaluation of field rock-water-oil

– Standard core flood methodology already developed

for low salinity

• Single well tracer test

– Follows screening and lab testing

• Field scale modeling to optimize deployment

– Basic procedure developed

Program Components

Enhanced Oil Recovery Institute

• Screening of fields (criteria under development)

– Higher T appears to increase effect

– Need formation water chemistry with low sulfate

(below saturation with anhydrite)

– Currently in water flood

– Available core and oil

Screening

Enhanced Oil Recovery Institute

E N H A N C E D O I L R E C O V E R Y I N S T I T U T E

Madison Fields in Wyoming

Top Ten Madison Fields in Wyoming

Screened for water compatibility

Field Reservoir Wells Oil BBL Low SO4 T © Gravity

BEAVER CREEK MADISON 17 1,024,776 YES 95 41

GARLAND MADISON 171 679,245 YES 50 21

LOST SOLDIER MADISON 24 385,218 YES 58 32

ELK BASIN MADISON 75 365,836 YES 65 29

OREGON BASIN MADISON 47 327,336 YES 50 20

WERTZ

DARWIN-

MADISON 19 205,918 YES 68 32

WHITNEY

CANYON-

CARTER CREEK MADISON 26 103,671 ? 110 42

TORCHLIGHT MADISON 21 42,238 ? 38 23

HAMILTON DOME MADISON 12 29,916 ? 35 18

SPENCE DOME MADISON 61 16,939 ? 25 19

Enhanced Oil Recovery Institute

• Laboratory program

– Standard core flood methodology already developed

for low salinity

– Determine effect in dolomite

– Determine effects of natural versus additive SO4

source

– Determine T effect

Experimental Program

Field Scale Models

Enhanced Oil Recovery Institute

Lab results

Rel perm

curves

Upscaled

models

E N H A N C E D O I L R E C O V E R Y I N S T I T U T E

The fundamental objective is to change

wettability in the reservoir to increase oil

recovery by changing the injected water

chemistry.

Adjusted Brine Chemistry

E N H A N C E D O I L R E C O V E R Y I N S T I T U T E

Conclusions

• This approach can provide simple and inexpensive technique to change wettability in carbonates

• Madison is 3rd largest producer in Wyoming

• Current production is 3.2 MMBO/year

• Doubling recovery in North Sea in chalk and limestone

• Not yet tested for dolomite

• Preliminary screening for water chemistry is underway

• Experimental design to test approach is ready