Learn lessons from the Nagaoka
ProjectShoichi Tanaka
The University of Tokyo
February 21, 2006.

International Workshop on CO２ Geological Storage , Japan ‘06

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Achievements of the Nagaoka Project -1
1.
2.
3.

Injection of 10,000 tons CO2 within an estimated range ofpressure.
Safe and sound injection operation of 500 days.
Detection of injected CO2 movement and changes of CO2
saturation with time-lapse geophysical well loggings.

February 21, 2006.

International Workshop on CO２ Geological Storage , Japan ‘06

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Achievements of the Nagaoka Project – 24. Monitoring images of CO2 accumulation inthe injection zone with time-lapse cross-wellseismic tomography.
5. Finding problems to improve computer codes.
6. Keeping integrity of the wells hit by theearthquake of M 6.8 encountered at theinjection operation.

February 21, 2006.

International Workshop on CO２ Geological Storage , Japan ‘06

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Features of the Nagaoka Project
1. Well site: Suburbs of Nagaoka City with apopulation of 290,000.
2. One injector and three observation wells system.
3. Low permeability of the injection zone:
From 1.6 md to 11.2 md.
6.7 md on average.

February 21, 2006.

International Workshop on CO２ Geological Storage , Japan ‘06

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Map of Nagaoka CityNagaoka
StationWell site

February 21, 2006.

8 km

International Workshop on CO２ Geological Storage , Japan ‘06

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Study of suitability of selected zone -1
1. Properties of cap rock: Mudstone.
Thickness: 136 m at injector.
Formation pressure gradient: 1.1 g/cm3
equiv.
2. Properties of injection zone: Sandstone.
Thickness: 12 m.
Formation pressure gradient: 1.09 g/cm
equiv.
Chloride ion concentration: 4,200 ppm
February 21, 2006.

International Workshop on CO２ Geological Storage , Japan ‘06

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Seismic section and lithology ofinjection well
Proposed position ofinjector
surfaceTop of Haizume
Formation, 954 m

Cap rock,
Mudstone,

Enlargedsection

136 m

Ic formation,
Sandstone,
1,090m~1,150m

February 21, 2006.

International Workshop on CO２ Geological Storage , Japan ‘06

Injection
zone, 12 m

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Study of suitability of selected zone -2
3. Step rate injection test of injection zone atinjector:
Maximum test pressure: 19.2 MPa
No indication of formation breakdown orleakage from the wellbore
Assumed injection pressure of simulation:
18.6 MPa(Ref. Maximum pressure at injection of40 t/d rate: 12.6 MPa)
February 21, 2006.

International Workshop on CO２ Geological Storage , Japan ‘06

8Assignments of the Nagaoka Project
9 Study of long-term monitoring system.
9 Study of formation pressure control system for
injection of large volume CO2 for a long period.
9 Study of flow of subsurface water in a depth of
1,000 m and deeper.
9 Measurement of curves of relative permeability toCO2 for various rocks.
9 Study of estimation and classification system ofcapacity and suitability of formations for CO2
geological storage similar to oil and gas reserves.
February 21, 2006.

International Workshop on CO２ Geological Storage , Japan ‘06

9Contribution of the Nagaoka Project toCO2 geological storage system
PublicAcceptanceCO2Geological Storage

CO2Capture

February 21, 2006.

International Workshop on CO２ Geological Storage , Japan ‘06

SystemCO2Injection

10Expectations• Implementation of full-scale geological storageof industrial CO2 in the near future to abate
environmental deterioration.

February 21, 2006.

International Workshop on CO２ Geological Storage , Japan ‘06

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Thank you for your attention.

February 21, 2006.

International Workshop on CO２ Geological Storage , Japan ‘0612