(1/25)PostPost--Injection Monitoring Injection Monitoring

to Ensure Safety of COto Ensure Safety of CO22 Storage Storage -- A case study at Nagaoka pilot site A case study at Nagaoka pilot site --

SaekoSaeko MitoMito1,1,* &* & Ziqiu XueZiqiu Xue1,21,2

11Research institute of Innovative Technology for the Earth (RITE)Research institute of Innovative Technology for the Earth (RITE)22Kyoto UniversityKyoto University

5th IEA GHG Monitoring Network Meeting, 2 June 2009

(2/25)

The COThe CO22 Storage Project WorkflowStorage Project Workflow

(After David White, IEA GHG International Summer School 2007 on CCS)

Design

Characterization

Site Selection

Performance & Risk Management

Decommissioning

Surveillance

CO2 Injection

PreparationConstruction

Monitoring

Pre-Operation Phase3-5 years

Operation Phase10~50 years

Post-CO2 injection Phase100+ years

PostPost--injection injection MonitoringMonitoring

(3/25)What happens after stopping COWhat happens after stopping CO22 injection?injection?

(CO(CO22 behaviors at the post behaviors at the post ––injection)injection)

Mobile COMobile CO22(Physical process)

Dissolved CODissolved CO22(Geochemical process)

Immobile COImmobile CO22(Physical process)

Mineralized COMineralized CO22(Geochemical process)

Image of trapping processes over time (IPCC 2005)

(4/25)

OutlineOutline

1. Overview of the Nagaoka pilot CO2 injection project

2. Results from Geochemical monitoringGeochemical monitoring for CO2-fluid-rock interaction (CHDT sampling)

3. Results from Geophysical monitoringGeophysical monitoring for mobile & immobile CO2 (Well loggings, seismic tomography)

4. Suggestions for CO2 monitoring at post-injection

(5/25)

Location of the Nagaoka Pilot COLocation of the Nagaoka Pilot CO22 Injection SiteInjection Site

TokyoRITE (Kyoto)5000m Gas production5000m Gas production

Active gas fieldActive gas fieldat Minami Nagaokaat Minami Nagaoka

(INPEX Co.)(INPEX Co.)

NagaokaNagaoka1100m1100m ReservoirReservoir

(6/25)

Overview of the Nagaoka Pilot ProjectOverview of the Nagaoka Pilot Project

Injection WellFormation dip: 15°

120m

40m

60m

IW-1 OB-2

OB-3

OB-4

Observation well

• Duration; FY2000-2007 funded by METI, Japan• Total amount of the injected CO2; 10,400 ton (2003.7~2005.1)• Reservoir; Pleistocene sandstone (Haizume Formation), 60m thick• Target injection layer; Zone 2, 12m thick• Conditions; 48oC, 11MPa• Permeability; ave. 7mD (pumping test)• Porosity; 23% Well Configrations

(7/25)

20000

10000

02002/01/01 2003/01/01 2004/01/01 2005/01/01 2006/01/01 2007/01/01 2008/01/01

40

20

0

150010005000-500

Field measurements during and post COField measurements during and post CO22 injectioninjection((Geophysical monitoringGeophysical monitoring))

OB-2OB-3OB-4

Well Loggings- Neutron- Sonic- Induction

Seismic tomography

Total; 10,400 ton

Rate; 20~40 ton/day

Inje

ctio

n ra

te(t-

CO

2/day

)

Cum

ulative amount

(t-CO

2 )

Date

37th

7th

Elapsed time from 7 July 2003 (day)

(8/25)

Neutron Logging (Neutron porosity; Neutron Logging (Neutron porosity; φn) @ OB) @ OB--22

1120

1116

1112

1108

Dep

th (m

MD

)

0.40.20.0φn

14th 16th 18th 20th 22nd 24th 26th 28th 30th 32nd 34th 36th15th 17th 19th 21st 23rd 25th 27th 29th 31st 33rd 35th 37th

Post-injection

Changes of the φn-0.15 0.05

BL

End of CO2 injection

Latest

(9/25)

Sonic Logging (PSonic Logging (P--wave velocity; wave velocity; VpVp) @ OB) @ OB--22

1120

1116

1112

1108

Dep

th (m

MD

)

3.52.51.5

Vp (km/sec)

14th 16th 18th 20th 22nd 24th 26th 28th 30th 32nd 34th 36th15th 17th 19th 21st 23rd 25th 27th 29th 31st 33rd 35th 37th

Post-injection

Changes of the Vp-1.0 0.5

BL

End of CO2 injection

Latest

(10/25)

Induction Logging (Resistivity; Induction Logging (Resistivity; ρ) @ OB) @ OB--22

14th 16th 18th 20th 22nd 24th 26th 28th 30th 32nd 34th 36th15th 17th 19th 21st 23rd 25th 27th 29th 31st 33rd 35th 37th

1120

1116

1112

1108

Dep

th (m

MD

)

753ρ (ohm-m) Changes of the ρ-0.5 1.5

Post-injection

BL

End of CO2 injection

Latest

(11/25)

20000

10000

02002/01/01 2003/01/01 2004/01/01 2005/01/01 2006/01/01 2007/01/01 2008/01/01

40

20

0

150010005000-500

Field measurements during and post COField measurements during and post CO22 injectioninjection((Geochemical monitoringGeochemical monitoring))

OB-2OB-3OB-4

Well Loggings- Neutron- Sonic- Induction

Seismic tomography

Total; 10,400 ton

Rate; 20~40 ton/day

Inje

ctio

n ra

te(t-

CO

2/day

)

Cum

ulative amount

(t-CO

2 )

Date

37th

7th

Elapsed time from 7 July 2003 (day)

Fluid sampling by CHDT @ OB-2Fluid sampling @ IW-1

(12/25)

Resistivity Changes with Time @ OBResistivity Changes with Time @ OB--22D

epth

(mM

D)

Elapsed time from 7 July 2003 (day)

CO2 injection Post-injection

Delta from the base line data

0.8

-0.4

0 ohm-m

0.4

1108

112016000

CHDT @ 1108.6 mCHDT @ 1108.6 m

CHDT @ 1114.0 mCHDT @ 1114.0 m

CHDT @ 1118.0 mCHDT @ 1118.0 m

Fluid sampling by Cased Hole Dynamics Tester

(13/25)

CHDT @ 1108.6 mCHDT @ 1108.6 m

CHDT @ 1114.0 mCHDT @ 1114.0 m

CHDT @ 1118.0 mCHDT @ 1118.0 m

Dep

th (m

MD

)

Elapsed time from 7 July 2003 (day)

CO2 injection Post-injection

1108

112016000

Water

Comp. mol%

H2 0.0

O2 0.2

N2 0.7

CH4 0.3

C2H6 0.0

CO2 98.8

Sample Chamber(volume 3.8 L)

Gas compositionGas composition

for details seeMito et al., Int. J. Greenhouse

Gas Control, Vol.2, 309-318, 2008

Sampling resultSampling result--11OBOB--2 @ 1114m2 @ 1114m：： Mostly free COMostly free CO22

Gas:3.5 L

(14/25)

CHDT @ 1108.6 mCHDT @ 1108.6 m

CHDT @ 1114.0 mCHDT @ 1114.0 m

CHDT @ 1118.0 mCHDT @ 1118.0 m

Dep

th (m

MD

)

Elapsed time from 7 July 2003 (day)

CO2 injection Post-injection

1108

112016000

Water:3.4~3.5 L

Gas:None

Sample Chamber(volume 3.8 L)

The change in salinity by increasing of HCO3

-

(7.2%) is roughly consistent with the change in resistivity (6.5%) @ 1118m.

300015000

HCO3- (ppm)

Before injection

1108.6m

1118.0m

Sampling resultSampling result--22OBOB--2 @ 1108.6m & 1118m2 @ 1108.6m & 1118m：：Mostly Formation WaterMostly Formation Water

Water Composition

(15/25)

8004000

Ca (ppm)

30150

Mg (ppm)

1.500.750.00

Fe (ppm)

Before injection

1108.6m

1118m

At the depth of 1118m (HCO3- conc. increased),

concentrations of Ca, Mg and Fe also increased.

Sampling resultSampling result--33OBOB--2 @ 1108.6m&1118m2 @ 1108.6m&1118m：：

CationsCations in the formation waterin the formation water

(16/25)

Geochemical Reactions at NagaokaGeochemical Reactions at Nagaoka

Verified from the field data using CHDT

• CO2 + H2O H2CO3* --- Solubility trappingSolubility trapping

• H2CO3* H+ + HCO3

- --- Ionic trappingIonic trapping

Inferred from the field data and batch experiments

• Calcite + H+ Ca2+ + HCO3-

• Plagioclase + H+ Ca2+ + Na+ + aluminosilicate• Smectite + H+ Mg2+ + Fe2+ + Fe3+ + K+ + Na+ + Ca2+

+ aluminosilicate

Simulated by ChemTOUGH• Ca2+ + HCO3

- Calcite + H+ --- Mineral trappingMineral trapping

(17/25)

Summary of Summary of GeochemicalGeochemical MonitoringMonitoring

• The CHDT (Cased Hole Dynamics Tester, Schlumberger) sampling confirmed stored CO2 as gas and dissolved phase.

• Because of low salinity (0.8wt%), dissolved COdissolved CO22 was was detecteddetected by the induction logging.

• We are working on modification of our long-term geochemical model to integrate the well logging results now.

(18/25)

Return to the Initial Formation PressureReturn to the Initial Formation Pressure

20000

10000

0

22003/01/01 2004/01/01 2005/01/01 2006/01/01 2007/01/01 2008/01/01

40

20

0

15001000500013

12

11

Inje

ctio

n ra

te(t-

CO

2/day

)C

umulative am

ount(t-C

O2 )

Date

IW-1

OB-4Pre

ssur

e (M

Pa)

Bottom Hole PressureBottom Hole Pressure

Elapsed time from 7 July 2003 (day)

(19/25)

(Juanes et al., 2006)

Driving Force of CODriving Force of CO22 ;;Pressure and/or BuoyancyPressure and/or Buoyancy

(20/25)

1120

1116

1112

1108

Dep

th (m

MD

)

753ρ (ohm-m)

Resistivity Change during Imbibition Phase @ OBResistivity Change during Imbibition Phase @ OB--2 2

BL

Latest

Elapsed time from 7 July 2003 (day)Post-injection

Delta from the base line data

0.8

-0.4

0 ohm-m

0.4

1600

End of CO2 injection

(21/25)Drainage and Imbibition PhaseDrainage and Imbibition Phase

(1116.0m @ OB(1116.0m @ OB--2) 2)

0.3

0.20.1

0.0

φ n

7

65

4ρ (o

hm-m

)

3

2

1Vp

(km

/sec

)

2003/01/01 2004/01/01 2005/01/01 2006/01/01 2007/01/01 2008/01/01Date

Imbibitionbreakthrough

CO2 injection period

Sgr?

(22/25)

6.5

6.0

5.5

5.0

4.5

ρ (ohm-m

)

0.80.60.40.20.0

CO2 Saturation

3.0

2.5

2.0

1.5

1.0

Vp (k

m/s

ec)

PP--wave velocity and resistivity wave velocity and resistivity vsvs COCO22 saturationsaturation(1116.0m @ OB(1116.0m @ OB--2) 2)

Vp

6.5

6.0

5.5

5.0

4.5

ρ (ohm-m

)

0.80.60.40.20.0

CO2 Saturation

3.0

2.5

2.0

1.5

1.0

Vp (k

m/s

ec)

ρ

(23/25)

Summary of Summary of GeophysicalGeophysical MonitoringMonitoring

• CO2 saturation has been decreasing at the lower part of the injection layer. The residual gas saturation will be determined in the actual reservoir at the Nagaoka site.

• Delay of P-wave velocity slowed down when CO2 saturation exceeded 20%. But changes in resistivity with CO2 saturation have kept increasing.

• Monitoring post-injection period is needed to clarify thetherelationship between the Prelationship between the P--wave velocity & the wave velocity & the resistivity and COresistivity and CO22 saturationsaturation. We are trying to adapt a methodology for accounting of COaccounting of CO22 in the reservoir.

(24/25)

Suggestions for COSuggestions for CO22 monitoring at postmonitoring at post--injectioninjection

•• Dissolved CODissolved CO22 vsvs ResistivityResistivity;Dissolution and mineral trapping are expected to reduce degree of rapid migration of mobile CO2. Understanding of geochemical reactionsgeochemical reactions helps to explain the longlong--term term behavior of CObehavior of CO22 and the changes in geophysical logs such as resistivity.

•• COCO22 saturation saturation vsvs PP--wave wave verosityverosity and Resistivityand Resistivity;Joint inversionJoint inversion of monitoring results of sonic wave and resistivity is key to account COaccount CO22 saturationsaturation.

•• Geochemical & GeophysicalGeochemical & Geophysical;Feedback of geochemical and geophysical monitoring results is necessary to improve long-term prediction of CO2behavior.

(25/25)

AcknowledgementsAcknowledgements

• This project is funded by Ministry of Economy, Trade and Industry (METI) of Japan.

• We thank staffs of ENAA, INPEX Co., Geophysical Surveying Co. Ltd., OYO Co., GERD and RITE involved in Nagaoka pilot CO2 injection project.

Thank you for your attention!Thank you for your attention!