POTENTIAL NEW USES FOR POTENTIAL NEW USES FOR OLD GAS FIELDS: OLD GAS FIELDS:

SEQUESTRATION OF SEQUESTRATION OF CARBON DIOXIDECARBON DIOXIDE

Paul R. KnoxSusan D. Hovorka

Bureau of Economic GeologyJackson School of GeosciencesThe University of Texas at Austin

Curtis M. OldenburgLawrence Berkeley National Laboratory

AGENDAAGENDA

• Overview of sequestration issues

• Application in oil and gas fields

• Enhanced gas recovery

• Pressure maintenance

• Wet intervals

• Summary

BureauofEconomic

Geology

GLOBAL CLIMATE CHANGE GLOBAL CLIMATE CHANGE INITIATIVEINITIATIVE

• “Today, I’m announcing a new environmental approach . . .”

• “We must foster economic growth in ways that protect our environment”

• “. . . set path to slow GHG emissions, and as science justifies - stop and then reverse that growth”

President BushFebruary 14, 2002

Compliments of H.D. Guthrie, NETL, DOE

BureauofEconomic

Geology

GCCI PATHWAY TO 2012:GCCI PATHWAY TO 2012:

120

140

160

180

200

2000 2004 2008 2012

1800

2200

2600

3000

3400

Gre

enh

ou

se G

as I

nte

nsi

ty (T

C/$

MM

GD

P)

Gre

enh

ou

se G

as E

mis

sio

ns

(MM

TC

E)

GCCI

EIA Reference Case

150 MMTCE Gapin 2012

18% REDUCTION IN GHG INTENSITY

Compliments of S.M. Klara, NETL, DOE

THE OPTIONSTHE OPTIONS

Reduce CarbonIntensity

Sequester

Energy efficiency

New technology

Fuel choice

Stop leaks, flares

Venting

Disposal Value-Added

Saline aquifers

Deep oceans

Biomass

EOR

EGR

ECBM

BureauofEconomic

Geology

ECONOMIC REALITIESECONOMIC REALITIES

• Early sequestration will be in value-added settings, where geographically available

• Gas fields: distributed volumes where subsurface is well-known

• Gulf Coast represents a combination of many CO2 sources and high-injectivity intervals

• Pipeline networks provide deliverability• Mechanisms to address emissions credits are in

the planning stages• Major oil companies have demonstrated

significant interest in geologic sequestrationBureauofEconomic

Geology

APPLICATION TO OIL APPLICATION TO OIL AND GAS FIELDSAND GAS FIELDS

GWC

GOC

OWC

WET INTERVAL

Brine-bearing Ss.

Gas-bearing Ss.

Oil-bearing Ss.

CO2-bearing Ss.

BureauofEconomic

Geology

DENSITY OF CODENSITY OF CO22 AND METHANE AND METHANE

BureauofEconomic

Geology

P (bar)

0 50 100 150 200

800

600

400

200

0

Gaslike CO2 Liquidlike CO2

60°C

80°C

80°C60°C

40°C

40°C

CO2

QAd1546c

CH4

VISCOSITY OF COVISCOSITY OF CO22 AND METHANE AND METHANE

QAd1547cP (bar)

60°C

40°C

80°C

60°C

80°C

40°C

CO27.0E-05

6.0E-05

5.0E-05

4.0E-05

3.0E-05

2.0E-05 CH4

0 50 100 150 200

BureauofEconomic

Geology

AGENDAAGENDA

• Overview of sequestration issues

• Application in oil and gas fields

• Enhanced gas recovery

• Pressure maintenance

• Wet intervals

• Summary

BureauofEconomic

Geology

MODEL SET-UPMODEL SET-UP

CO2 injection

CH4 production

Gas reservoir

Water table

BureauofEconomic

Geology

QAd1548c

6600 m100 m

Scenario I – No production during CO2 injectionScenario II – Production rate offsetting injection rate

MODEL RUNSMODEL RUNS

BureauofEconomic

Geology

Scenario II

PRESSURE AND GAS FRACTIONPRESSURE AND GAS FRACTION

BureauofEconomic

Geology

1

0.9

0.8

0.7

0.6

0.5

130

120

110

100

90

80

70

60

50

40

30

Year

1940 1950 1960 1970 1980 1990 2000 2010

III

II

IP

Historical CH4 production

CH4Xgas

QAd1550c

Scenario I – No production during CO2 injectionScenario II – Production rate offsetting injection rate

INCREMENTAL PRODUCTIONINCREMENTAL PRODUCTION

BureauofEconomic

Geology

1950 1960 1970 1980 1990 2000 20202010

Historical production period Projected

1.5E+08

1E+08

5E+07

0

Year

II

I

No CSEGR

Q Ad1 551 cScenario I – No production during CO2 injectionScenario II – Production rate offsetting injection rate

CSEGR: OUTSTANDING ISSUESCSEGR: OUTSTANDING ISSUES

• Economic Feasibility

• Field Testing

•Economic feasibility evaluated by Oldenburg, Stevens*, and Benson (2002) using example from California’s largest gas reservoir

* Advanced Resources International, Inc.

ECONOMIC PARAMETERSECONOMIC PARAMETERS

• Interval is high-porosity, high-permeability sandstone at 5,000 ft depth (Rio Vista field)

• 25 injectors (125 MMcfd, 6,500 tons/d)• 18 producers (peak 45 – 90 MMcfd)• 8 monitor wells• 15 years duration• Costs included mix of new and recompleted

wells, pipelines• Produced gas CO2 content:1-5 yrs = 0%, 5-10 yrs

= 5%, 10-15 yrs = 25%

ECONOMIC OUTPUTECONOMIC OUTPUTEconomic Analysis of CSEGR at California Depleting Gas Field

$2.50

$3.00

$3.50

$4.00

$4.50

$5.00

$5.50

2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0

Breakeven CO2 Supply Cost ($/t; pure, high-P, at pipeline)

CO2/CH4 Volume Ratio = 3.0

CO2/CH4 Volume Ratio = 2.0

CO2/CH4 Volume Ratio = 1.5

ECONOMIC

SUB-ECONOMIC

ECONOMIC

SUB-ECONOMIC

SUB-ECONOMIC

ECONOMIC

Improved Production Technology

Met

hane

val

ue

From Oldenburg, Stevens, and Benson (2002)

BOTTOM LINEBOTTOM LINE

• For CO2/CH4 volume ratio = 1.5, need CO2 cost ~ $10/t.

• Economics are sensitive to physical processes, specifically

CO2/CH4 volume ratio, mixing, and breakthrough times.

• Economic feasibility will be reservoir-specific.

• Overall conclusion is that CSEGR will require subsidy under

current conditions, but that increases in CH4 price or

decreases in CO2 supply costs can make CSEGR profitable at a

field like Rio Vista.

• Field demonstration project essential to realistic assessment

in the Gulf Coast

AGENDAAGENDA

• Overview of sequestration issues

• Application in oil and gas fields

• Enhanced gas recovery

• Pressure maintenance

• Wet intervals

• Summary

BureauofEconomic

Geology

SEQUESTRATION AT THE SEQUESTRATION AT THE GAS-OIL CONTACTGAS-OIL CONTACT

BureauofEconomic

Geology

Water

CO2Flow of gas and oil into wellbore

Flow of CO2 into reservoir

Perforations

Producing gas well

Producing oil well

CO2 injection well

QAc8550c

CO2 CO2

AGENDAAGENDA

• Overview of sequestration issues

• Application in oil and gas fields

• Enhanced gas recovery

• Pressure maintenance

• Wet intervals

• Summary

BureauofEconomic

Geology

WET INTERVALSWET INTERVALS

• Increase overall sequestration volume

• Existing subsurface infrastructure

• Existing surface infrastructure (pipelines)

• Abundant subsurface data

• Subsurface activities familiar to local communities and regulators

• U.S. Department of Energy-funded Gulf Coast pilot in permitting stages

BureauofEconomic

Geology

BRINE PILOTBRINE PILOT

• Purpose: demonstrate feasibility and monitoring techniques, evaluate model predictions

• Setting: salt dome flank, Frio sandstone, 5,000 ft depth.

• Scope: < 5,000 tonnes (90 MMcf) over 20 days of injection

• Monitoring: tracers, pressure and temperature, logs, seismic

Power plants

Industrial sourcesHigh sand trend

in the Frio

Houston

20 milesBureau

ofEconomic

Geology

BRINE PILOT LOCATIONBRINE PILOT LOCATION

Pilot site

CONCLUSIONSCONCLUSIONS

• Preparations are being made in the event that geologic sequestration becomes necessary

• Sequestration can substantially enhance production from mature gas reservoirs and is economic with low-cost CO2 supplies

• Sequestration seems a logical option to maintain reservoir pressure and facilitate simultaneous oil and gas production

• Sequestration has the potential to extend field life, increase ultimate recoveries, increase production rates, and add new revenue streams to mature fields.

BureauofEconomic

Geology

ACKNOWLEDGEMENTSACKNOWLEDGEMENTS

This work was supported in part by the

Assistant Secretary for Fossil Energy,

Office of Coal and Power Systems through the

National Energy Technology Laboratory, and by

Lawrence Berkeley National Laboratory under

Department of Energy

Contracts No. DE-AC03-76SF00098 and

No. DE-AC26-98FT40417