CO2地中貯留安全性評価技術開発の取り組み
Research and Development of Safety Assessment
Technology for CO2 Storage in Deep Saline Aquifer

せつじきゅう薛 自求（xue @ rite.or.jp）
Research Institute of Innovative Technology for the Earth (RITE)

公益財団法人 地球環境産業技術研究機構

Contents
Safety / Risk Assessment in CO2 Storage・Definition, Diversity and Uncertainty
・Safety / Risk Assessment & Management

Geologic Modeling and Monitoring Tech.
・Heterogeneous Reservoir (Vertical & Lateral Variations)・Monitoring, Verification, Accounting (MVA)・Fiber Optic Sensing (Distributed, Repeatable, Permanent)

Risk Management & Communication
・Reducing the Levels of Uncertainty and Risk
・Scientific Knowledge and Evidence-based Risk
Communication2Safety/Risk Assessment in CO2 Storage (1/3)
・Definition, Diversity and Uncertainty
 Risk: the possibility due to uncertainties and threats affecting storage process,included in all activities with different degrees
 Identifying the risks
 Analysing the risks
 Evaluating the risks
 Monitoring and reviewing the risks
Controlling the risks (without further risk treatment required)

Mitigating the risks  Securing the safety(Safety assessment = Risk assessment) Business or investment-related risks (Fiancial & Market), Communication
risks (Stakeholders), Global risks without CCS (Climate change)
3Safety/Risk Assessment in CO2 Storage (2/3)
・Definition, Diversity and Uncertainty

High Subsurface Uncertainties:
 Multiple and site-specific subsystems (injection & monitoring wells,aquifers, caprocks, aquitards, freshwater, faults….)
 Many interacting components (rock minerals, CO2,formation fluids….)

 Various models (geological model, reservoir model,
geochemical model, geomechanical model….)

Advantages and Limitations of Technologies
used in All CO2 Storage Activities!

4Safety/Risk Assessment in CO2 Storage (3/3)
・Potential Risks
Risk profile ＠CO2 injection site（site-specific）

Losses of Injectivity, Capacity and Containment,
Induced Seismicity, Environmental Impacts
5Research Areas & Program (US/DOE)(DOE, 2015)

Onshore/ Offshore(Gulf of Mexico)

・R&D focused on: Cost (Capture)
and Confidence (Storage),・Demonstrations: Integrationand Learning
6

Storage Capacity & Monitoring Tech (1/3)

Oxand Reservoir characterization: Heterogeneity and Injectivity
Paasch, 2015
Injection: 2008-2011
Injection: 2011-

Injection: 2008-2011
Paasch, 20157

@ Snohvit

Paasch, 2015

Integrating aspects from both 3D seismic and sequence stratigraphy

8Application of Sequence Stratigraphy@ Nagaoka (injection well)
Clay content, γ-ray log

CO2Injectivity(PLT)

Porosity, Permeability
Ito et al., 2015

Detailed information at wells: Local to Spatial
9

Monitoring Techs & Cost-Benefit Ranking
2D / 3D Seismic

Fiber-optics
P&T

Down-hole
P&T

Down-hole Microseismic

QUEST/MMV

10

Measuring Wave Velocity while ScanningHigh pressure vesselZhang et al., 2014

Sandstone(ϕ5cm,10cm)
11Lab test: CO2 Saturation Image & Waveform
X-ray CT images
Waveforms during drainage imbibition

Zhang et al., 2014

Vp, Vs, Vp/Vs vs CO2 Saturationin highly heterogeneous core samples
12

CO2 Monitoring with Integration of S-wave
Ocean Bottom Cable
Field pilot test (offshore)

3C geophone

Lab test

13

Measuring Impedance while Scanning
Complex electrical impedance
10Hz ~ 1MHz

Liu et al., 2015

An example of Cole-Cole plot
during fluid injection

Electrical Impedance vs CO2 Saturation
14

Pressure Monitoring @ Decatur (Illinois)
Buildup due to CO2 injection

Locke et al., 2015?

??

Geomechanics: Pressure change  Deformation

15

Uplift Caused by Pressure Buildup
at In Salah During CO2 Injection
Pressure buildup dependingonreservoir porosity & permeability,CO2 injection rate & volume.

Uplift at ground surface
How tointerpret?

Pressure buildup at subsurface

Need continual strain data along depth? 16

Wellbore Deformation Tool
BSM by Baker Hughes

Murdoch et al., 201417

Murdoch et al., 201418

Single  Multi  Distributed(Dria, SPE/DL 2012)19

Application of Fiber Optics＠QUESTQUEST Project20

Fiber Optics: Water Injection Test
New well for water injectionFiber cable installed well

5.5 mcasing
Temp sensor

Optic Fiber Cable

cement230 m

300 m

21

Strains
estimated during water injection
StartStopStart
StartStop
30.6με(-4.8 GHz)

-30.6με(4.8 GHz)

１層アーマードケーブルのレイリー結果（温度補償なし）

22

Response to Water Extraction (1/2)

Ground water well #4

Fiber Installed Well

Ground water well #3
23

Response to Water Extraction (2/2)

-159m

-197m
-203m
-219m

-168m
-173m
-179m
-206m
-212m
-228m
-235m
-239m

24

Impacted Zone Detected during CO2 Injection
1 hr later3 hrs later

5 hrs later

10 hrs later

15 hrs later

Impacted zone
detected from fiber cable
Xue et al., 2015

EMI

perforated25

Impacted Zone Detected at the Deep Well

Well depth: 880m

Strains estimated at different depths in N2 injection
26

Combined effects of temperature andstrain in recorded frequency shifts
12/7 12:00

12/8 8:53 12/7 12:00

12/8 8:53

0Brillouin shift scattering

Rayleigh shift scattering

Depth [m]

200

400

600752m

800(GHｚ）(MHｚ）
27

Temperature and Strain Separation from the Observed
Frequency Shifts in Rayleigh & Brillouin Scattering
12/7 12:00

12/8 8:53 12/7 12:00

12/8 8:53

0200
Depth [m]Temp change
Strain change

400600752m

800

deg. C.

microstrain

28

Distributed Acoustic System（DAS）
0m

0500

Time (ms)1000

1500+0.05V

200m

Packer position（295m）

Potential use for VSP
in CO2 monitoring,well integrity

400m

600m

An example of tube waves during packer operation-0.05V29

Lab test: CO2 front migration detection
CO2 migrating from BTM to TOP

TOPBTM

Leakage detection
in abandoned wells!

TOP⑩⑨⑧⑦⑥⑤④③BTM

A field test planned this year !

30Geothermal, Conventional and Unconventional Oil & Gas,
Waste Water Disposal, CCS

National Academy of Sciences, 201331

A Dense Microseismic Monitoring Network@Tomakomai (offshore)
Onshoreseismometer

Observation well OB‐2 for
Moebetsu Formation(vertical)

2 Injection wells(Deviated)

Observation well OB‐1 for
Takinoue Formation
converted from survey wellObservation well OB‐3
for Takinoue Formation(vertical)(Deviated)

OBS
Working area of 3D seismic survey
OBS

OBS

OBS

OBS: Ocean Bottom Seismometer

Tanase, 201532

A Dense Microseismic Monitoring Network@ Decatur, Illinois (onshore)

Finley., 201333

Finley., 201334
34

Finley., 201335

Summary Information about Historical Felt Seismic Events
Caused by or Likely Related to Energy Tech Develop in US

National Academy of Sciences, 201336

Controlled CO2 Release Experiment in the Ocean
QICS: UK – Japan Collaboration
Quantifying and Monitoring Potential Ecosystem Impacts• CO2 Leakage detection using thegeophysical, acoustic, geochemical
methods• Evaluation of ecological impacts
by gene-analysis, photo-graphics
observation etc.

QICS special issue: CCS and the Marine Environment
21 research papers, Int. J. Green Gas Control: Vol.38, 201537

Simulating Leaked CO2 in the Ocean
Modeling area driven by temporally variable heat flux and windstress at sea surface ⇒ Able to represent seasonal variation• CO2 leakage: 250 tonnes/year within 150m×150m

38

ΔpCO2 predicted in two flow fields
at same leakage rate
Strong flow field

Weak flow field

39

Effective concentration
ΔpCO2 (µatm)

Threshold for Ecological CO2 Impacts
Estimated from a Biological Impact Database

90%

50%

10%

Exposure time (hour)
40

EIA at the Tomakomai offshore project
Act for the Prevention of Marine Pollution andMaritime Disasters• May 2007: The act was amended for permit procedureon dumping CO2 stream into sub-seabed formation.

• Preliminary Assessment Document“Estimation of CO2 dispersion and its impact
assessment on the assumption that stored CO2
leaks out to the sea”
41

Learning from Demonstration Projects
Understanding Uncertainty and Managing Risks
Risk＝Consequence Severity x Probability
Scientific Knowledge & Evidence-based Risk Communication

Risk＝Hazard + Outrage

Reducing Uncertainty／Mitigating Risks
to the Manageable Levels !

42