Fundamentals of CO2-Enhanced

Oil Recovery

Vanessa Nuñez-Lopez

Gulf Coast Carbon Center, Bureau of Economic Geology

Jackson School of Geosciences, University of Texas at Austin

Birmingham, Alabama

June 7-16, 2015

Research Experience in Carbon Sequestration (RECS)

Enhanced Oil Recovery (EOR) is…

• Oil recovery by

injection of fluids not

commonly present in

the reservoir

• Excludes pressure

maintenance or

waterflooding

• Not necessarily

tertiary recovery….

Recovery Mechanisms

Source: Adapted from the Oil & Gas Journal, Apr. 23, 1990

Conventional

Recovery

Enhanced

Recovery

Tertiary

Recovery

Other

Chemical

Solvent

Thermal

Pressure

MaintenanceWater - Gas Reinjection

Secondary

Recovery

Artificial LiftPump - Gas Lift - Etc.

Waterflood

Natural Flow

Primary

Recovery

EOR using CO2

Typical Production: Weyburn Unit (Midale Sand)

CO2-EOR (The basics)

CO2-EOR is a technology that targets the residual oil in depleted oil

reservoirs by the injection of carbon dioxide (CO2).

What is it?

How does it work?

CO2 is a solvent: it mixes with

the oil

Where is it applied?

In depleted light-oil reservoirs that have gone through

primary recovery (natural flow) and, in most cases,

secondary recovery (mainly waterflooding).

• Oil expands (swells)

• Oil viscosity is reduced

• Interfacial tension (IT) disappears*

What holds the fluids in a capillary?

air and water

air, water and oil

Different interfaces curve

differently!

To move, have to overcome

interfacial tension.

interface

molecules

near

interface

Some everyday effects of capillarity

Images from

Wikipedia

The process…

U.S Department of Energy - NETL

Recycling

Water Pump

Surface Infrastructure

U.S Department of Energy - NETL

Production manifoldProduction well

Injection well

Separator

Surface Infrastructure

U.S Department of Energy - NETL

CO2 recycling facility

CO2 compressor

From Melzer Consulting

CO2-EOR Case Studies

Active World, U.S., and Permian Basin CO2 EOR Projects

U.S. CO2-EOR Operations, CO2 Sources: 2014

Current CO2 Infrastructure in the US is EOR

Dominant

Major US CO2 pipelines

ARI 2012

CO2-EOR Production: Historical

CO2 Supply Shortage

Recent Expansion of Natural CO2 Supplies for EOR

Denver Unit of the Wasson Field, West Texas

More than

120 million

incremental

barrels

through

2008

Typical EOR Production

Specific CO2 Floods

Means San Andres Unit

2000

4000

6000

8000

10000

12000

14000

16000

18000

1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992

BO

PD

Year

Began (

Nov.

'83)

CO

2In

jection

Continued Waterflood

18% HCPVCO

2Injection

37.2

38.7

3.2

11 (7)*

To Date

Ultimate

P+S EOR

Recovery, % OOIP

*Original EOR Estimate

Seminole San Andres Unit

0

10000

20000

30000

40000

50000

60000

70000

80000

1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992

BO

PD

Year

Recovery, % OOIP

*Original EOR Estimate

45.2

47.2

6.7

17 (17)*

To Date

Ultimate

P+S EOR

Continued Waterflood

25% HCPVCO

2Injection

CO

2In

jectio

n

Be

ga

n (

Ma

r. '8

3)

Ford Geraldine Unit

0

500

1000

1500

2000

1978 1980 1982 1984 1986 1988 1990 1992

BO

PD

Year

Began (

Feb. '8

1)

CO

2In

jection

21.8

21.8

7

15 (8)*

To Date

Ultimate

P+S EOR

Recovery, % OOIP

*Original EOR Estimate 46% HCPVCO2 Injection

20 MCF/D CO2Source Secured

End ofWater Injection Continued Waterflood

100

10,000

1,000

1987 1988 1989 1990 1991 1992 1993 1994

(From Folger and Guillot, 1996)

Actual Oil

Continued

Waterflood

Ba

rre

ls/D

ay

Year

Sundown Slaughter

Began (

Jull.

‘92)

CO

2In

jection

NETL, 2008

CO2 Injection volume matters!

feet F % md feet API cp %HCPV %OOIP MCF/STB MCF/STB -

field scale projects

Dollarhide TX Trip. Chert 7,800 120 17.0 9 48 40 0.4 30 14.0 2.4 1985

East Vacuum NM Oolitic dolomite 4,400 101 11.7 11 71 38 1.0 30 8.0 11.1 6.3 1985

Ford Geraldine TX Sandstone 2,680 83 23.0 64 23 40 1.4 30 17.0 9.0 5.0 1981

Means TX Dolomite 4,400 100 9.0 20 54 29 6.0 55 7.1 15.2 11.0 1983

North Cross TX Trip. Chert 5,400 106 22.0 5 60 44 0.4 40 22.0 18.0 7.8 1972

Northeast Purdy OK Sandstone 8,200 148 13.0 44 40 35 1.5 30 7.5 6.5 4.6 1982

Rangely CO Sandstone 6,500 160 15.0 5 to 50 110 32 1.6 30 7.5 9.2 5.0 1986

SACROC (17 pattern) TX Carbonate 6,400 130 9.4 3 139 41 0.4 30 7.5 9.7 6.5 1972

SACROC (14 pattern) TX Carbonate 6,400 130 9.4 3 139 41 0.4 30 9.8 9.5 3.2 1981

South Welch TX Dolomite 4,850 92 12.8 13.9 132 34 2.3 25 7.6

Twofreds TX Sandstone 4,820 104 20.3 33.4 18 36 1.4 40 15.6 15.6 8.0 1974

Wertz WY Sandstone 6,200 165 10.7 16 185 35 1.3 60 10.0 13.0 10.0 1986

producing pilots

Garber OK Sandstone 1,950 95 17.0 57 21 47 2.1 35 14.0 6.0 1981

Little Creek MS Sandstone 10,400 248 23.4 75 30 39 0.4 160 21.0 27.0 12.6 1975

Majamar NM Anhydritic dolomite 4,050 90 10.0 11.2 49 36 0.8 30 8.2 11.6 10.7 1983

Majamar NM Dolomitic sandstone 3,700 90 11.0 13.9 23 36 0.8 30 17.7 8.1 6.1 1983

North Coles Levee CA Sandstone 9,200 235 15.0 9 136 36 0.5 63 15.0 7.4 1981

Quarantine Bay LA Sandstone 8,180 183 26.4 230 15 32 0.9 19 20.0 2.4 1981

Slaughter Estate TX Dolomitic sandstone 4985 105 12.0 8 75 32 2.0 26 20.0 16.7 3.7 1976

Weeks Island LA Sandstone 13,000 225 26.0 1200 186 33 0.3 24 8.7 7.9 3.3 1978

West Sussex WY Sandstone 3,000 104 19.5 28.5 22 39 1.4 30 12.9 8.9 1982

Field Projects ==> 11.7 6.3 AVERAGE

10.4 6.3 MEDIAN

Pilot Projects ==> 12.5 6.4 AVERAGE

8.9 6.0 MEDIAN

Gross Net

CO2 Utilization Ratio Gross Net

US Domestic Oil Resource Base

Ferguson et al., 2009

ROIP “Stranded” - 400 Billion Barrels

(of 596 billion barrels OOIP)

CO2-EOR Potential in the U.S.

Gulf Coast CO2-EOR Potential Distribution4.7 billion barrel incremental oil

2.6 billion tons storage potential

Nuñez-Lopez, 2008

*Stored volumes do not include losses during Recycle

***Retention is defined as a percentage of purchased volumes

Is CO2 stored during EOR? Yes!

BIG SKY

WESTCARB

SWP

PCOR

MGSC

SECARB

MRCSP

DOE Regional Sequestration Partnerships

Carbon Sequestration Potential in Oil Reservoirs

CCPI

ICCS Area 1

FutureGen 2.0

Major CCUS Demonstration ProjectsProject Locations & Cost Share

Southern CompanyKemper County IGCC Project

IGCC-Transport Gasifier w/Carbon Capture

~$2.67B Total; $270M DOEEOR – 3 M TPY 2014 start

NRGW.A. Parish Generating StationPost Combustion CO2 Capture

$339M Total; $167M DOEEOR – 1.4M TPY 2014 start

Summit TX Clean EnergyCommercial Demo of Advanced

IGCC w/ Full Carbon Capture~$1.7B Total; $450M DOEEOR – 3M TPY 2014 start

HECACommercial Demo of Advanced

IGCC w/ Full Carbon Capture~$4B Totall; $408M DOEEOR – 3M TPY 2018 start

Leucadia EnergyCO2 Capture from Methanol Plant

EOR in Eastern TX Oilfields

$436M - Total, $261M – DOE

EOR – 4.5 M TPY 2015 start

Air Products and Chemicals, Inc.CO2 Capture from Steam Methane Reformers

EOR in Eastern TX Oilfields

$431M – Total, $284M – DOE

EOR – 1M TPY 2013 start

FutureGen 2.0Large-Scale Testing of Oxy-Combustion w/ CO2

Capture & Sequestration in Saline Formation~$1.3B Total; ~$1.0B DOE

SALINE – 1.3M TPY 2016 start

Archer Daniels MidlandCO2 Capture from Ethanol Plant

CO2 Stored in Saline Reservoir

$208M Total; $141M DOE

SALINE – ~1 M TPY 2013 start

Courtesy NETL 2014

Petra Nova Carbon Capture Project

Commercial-scale post-combustion carbon capture project at

NRG's WA Parish.

50/50 joint venture between NRG and JX Nippon Oil & Gas

Exploration

Received $167 million from DOE as part of the Clean Coal Power

Initiative Program (CCPI)

Capture 90 % of the carbon dioxide (CO2) from a 240 MW

slipstream of flue gas and use or sequester 1.6 million tons of

CO2 a year.

Captured CO2 will be used to enhance production at mature oil

fields in the Gulf Coast region

Denbury’s Hastings Carbon CCUS Project(DOE Industrial Carbon Capture and Storage Initiative)

Air Products & Chemicals, Inc. (Port Arthur, TX)-Air Products is

capturing and injecting one million tons of CO2 per year from

existing steam-methane reformers in Port Arthur, Texas (DOE

share: $253 million)

Leucadia Energy, LLC (Lake Charles, LA)-Leucadia will capture

and sequester 4.5 million tons of CO2 per year from a new

methanol plant in Lake Charles, LA (DOE share: $260 million)

Denbury’s Hastings Carbon CCUS Project

Construction of 24’, 325-mile Green Pipeline for transporting CO2 from

Donaldsonville, Louisiana, to oil fields in Texas finished in 2010.

Natural CO2 injection for enhancing oil production started in December 2010.

Air Products CO2 injection started in December 2012.

Questions?

Practical Demonstrations

CCS Critical Parameters

Sink Capacity

How much CO2 can we store?

Where will the CO2 flow (CO2 distribution)?

How will the CO2 partition? (free phase, dissolved, mineral bound)

How will the CO2 distribution evolve with time?

Formation Injectivity

How fast can the CO2 be injected?

In what locations and how (well placement, well type)?

Storage Integrity

Vertical leakage (through wells and faults)

Lateral leakage (out of pattern migration)

Petrophysical properties relevant to

aquifer storage

• Porosity– Fraction of bulk rock volume

containing fluid

• Larger porosity means

smaller footprint for given

CO2 volume

pore space rockV V

Saturation – fraction of pore

space filled with a particular

fluid phase

porespace

phase

phaseV

VS

CO2 rock 2COV V S

From Steve Bryant

Porosity

Petrophysical properties relevant to

storage rates• Permeability

– Rock property that relates driving force (pressure gradient) to flux (flow

of single phase fluid)

• Darcy’s empirical law

• Large permeability requires less pressure to inject a given CO2 rate

• Heterogeneous permeability can lead to CO2 plume moving in

unexpected directions or distances

2

141.2

rCO e w

D

k kh P Pq =

μB P + S

ln (r e/r

w )From Steve Bryant

Storage rates: multiple injection wells offer

obvious advantage over single injection well

• Good news: multiple injectors enable greater overall

injection rate than single well

• Bad news: multiple injectors interfere with each

other

1 well 4 well2 well

Reservoir

N

Open System (or Early time Closed System)

• pressure front around well propagates

outward into new, undisturbed rock

• no boundary encountered

• map view• circular drainage area• vertical wellbore in the

center• Pwf>Ppore

• fluid moves from high to low pressure

• pressure wave moves out from wellbore

Pressurized zone

Wellbore

Reservoir

N

Early to Late Time in Closed System• pressure front encounters a pressure boundary

EOR decreases risk by active control

of area of elevated pressure and area

of CO2 plume

Saline injection map

Injection well

EOR Pattern flood map

Production well

Monitoring well

CO2 plumeElevated pressure

From Sue Hovorka

Exercise!