Geological Storage - Risk Assessment & Monitoring

Transcription

1 Geological Storage - Risk Assessment & IEA GHG Summer School, Norway 24th August 2010 David White Schlumberger - over 80 years of history & technology First electrical log run by Marcel and Conrad Schlumberger Pechelbronn, Alsace, France September 5, 1927 Schlumberger today People: 80, Nationalities Working in over 80 countries Services: Reservoir characterization Reservoir production Drilling & Measurements Integrated Project Management 2009 Financials: $22.7 billion revenue $3.1 billion net > $800 million on Research & Development 3 1

2 Schlumberger Carbon Services Highlights People A full Asset team dedicated to CO 2 storage >100 experienced technical staff Experience in CO 2 storage More than 10 years experience in CO 2 storage Numerous ongoing projects worldwide including the regional partnerships in the USA, the Otway project in Australia, Ketzin in Europe. Technology for CO 2 storage Unique set of process and technologies for CO 2 storage Dedicated research and engineering activities More than 100 publications on CCS 4 Global CO 2 Storage Sites/Projects with Schlumberger Activity Weyburn, Canada Snøhvit, Barent Sea Sleipner, North Sea Large CCS projects In Salah, Algeria >60 CCS projects/studies globally Gorgon Field, 130 km offshore NW Australia Global CO 2 Storage Sites/Projects with Schlumberger Activity North Sea customer A American Electric Power Company, Inc. (Ohio) North Sea customer B Vattenfall Jaenschwalde PGE Belchatow Repsol Spain Site pre-selection for ENI (4 sites) Lassie, Australia Illinois Basin - Decatur Project Reggane, Algeria CO2CRC Otway Project Southern Company Services, Inc. (Alabama) >60 CCS projects/studies globally 2

3 Risk assessment and for CO 2 storage! Why Monitor? Manage Risk Risk = (Impact of Undesirable Occurrence) x (The Probability of its Occurrence) But it is not that simple Risk Perception Public vs. Experts Public Feels - The Dread Factor - reacts very negatively to worst-case risk assessments, Public: Risk Size= ( Known factor)*( Dread factor) Experts Calculate - tend to rely on quantifiable realist perspectives, Risk Size= (Probability)*(Loss) Expert risk studies are rarely effective for convincing the public that a proposed project is safe. Thesis by Gregory Singleton, MIT May

4 Risk Perception Public vs. Experts Public Feels - The Dread Factor - reacts very negatively to worst-case risk assessments, Public: Risk Size= ( Known factor)*( Dread factor) Experts Calculate - tend to rely on quantifiable realist perspectives, Risk Size= (Probability)*(Loss) Expert risk studies are rarely effective for convincing the public that a proposed project is safe. Thesis by Gregory Singleton, MIT May 2007 CCS Risk Types GENERAL RISKS Public acceptance Economic Legal Key Concerns: Leakage & Seismicity TECHNICAL RISKS: Extreme events (major releases) Ground fresh water resources contamination Soil contamination Leaks Risk Acceptance Criteria Standards Regulations and Policies Risks can be managed we do it all the time Evaluate & Understand Model & Simulate Measure & Monitor Mitigate Experiment and Demonstrate (I bet they tried it with a dummy first and it might be a fake!) 4

5 Finding the right Storage Site What do we need? Capacity: The amount of CO 2 that can be safely stored Injectivity: The ease with which the CO 2 can be injected Containment: The ability to store CO 2 safely and permanently Other: Environment Infrastructure Regulation Public opinion Finance the best risk reduction approach is to choose the right site in the first place CO 2 3 objectives Freshwater aquifer #3: Monitor the environment Containment Well Integrity #2: Watch possible leakage paths Sealed fault #1: Watch stored CO 2 Boundaries CO 2 injection Abandoned Drawing from the Oilfield: Static and Dynamic Modeling Workflow Data input Surface imaging Mapping Log interpretation and correlation History match Fault and Fracture modelling ECLIPSE 3-D flow simulation Geochemistry Geomechanics 3D Geological model Reservoir and Aquifer property population 5

6 CO 2 Storage Site Modelling Workflow Surface imaging Mapping EM survey interpretation Data input Information management GIS database Calibration History match Post processing Presentation Log interpretation Well correlation Surface identification Surface/subsurface interaction Data analysis Facies modelling Fault modelling Fracture modelling Hydrodynamic test analysis Eclipse 3D flow simulation Geochemistry Geomechanics 3D Geological model 3D Property model of the Reservoir and the Overburden Uncertainty analysis Upscaling processes Reservoir and Aquifer property population Zooming in on the sub-surface The Need for Technology: Hi-Res versus Conventional 6

7 Storage Lifecycle And where is CO2 storage readiness Development CO 2 Injection Closure Appraisal Performance Management & Risk Control Post closure Pre Selection Post liability transfer Pre-injection Injection Post-injection 19 Designing a monitoring plan Reduce Risk & Optimize Performance: Added value for the operator Minimize Costs: For each technique, For the overall plan over time Plan Abide by laws & Regulations: EU CCS, EU ETS, state law Site & technical constraints: Deployment restrictions, Measurement sensitivity Performance & Risk Analysis for CO 2 Storage Measurements (characterization) Seismic Data s Models Structure 3D static Dynamic Sensor selection and specification Sensor response prediction Measurements () CO 2 injection CO 2 location Storage integrity CO 2 migration Cap rock failure Well materials degradation Measurement interpretation Model update Performance & Risk Assessment Injection efficiency CO 2 in place Leakage scenarios & rates Risk ranking sensor placement Intervention, Remediation 7

8 Reducing Uncertainty & Risk over time Uncertainty & Risk Characterisation Simulation Site Design & Strategy Certification at start Injection start Uncertainty & Risk Simulation Intervention & Remediation Injection stop Transfer of liabilities Time challenges Range of scales Time - from the very short to the very long Space - from the very small to the very large You can t directly measure what you want to Spatial distribution and concentration of CO 2 Sealing boundaries, capacity, permeability. You can t measure where you want to Confined to the surface or s BUT you measure what you CAN and construct models Consistent with available information Improve with time With some predictive power (within limits) Questions for Designing a System What do I want to monitor? What property change can I monitor? What variation am I considering? What measurement technique to use? What should be my sensor specifications? Where should I place my sensor? For how long? How can I deploy it? How can I interrogate it? How can I interpret the measurement? CO 2 movements, leaks P, CO 2 Saturation, Resistivity Accuracy / Precision Surface, Obs. Well (Permanent, Logging ) Operation phase, surveillance 8

9 CO 2 Operational Assurance (Environment and HSE environment) monitoring freshwater Freshwater aquifer fractured cap rock Containment Tracking the CO2 plume Verification (Watch possible leakage paths) Sealed fault open fracture leaking Well Integrity injection monitoring abandoned Injection Old spill point Spill points Integrated CO2 Storage Programme Geophysical techniques: Logging: Sampling: Permanent sensors: Seismic, VSP s, EM techniques, Microseismics Saturation (Resistivity, Sigma), Well integrity (Casing corrosion, cement bond) Pressure, Fluid properties, CO 2 concentration Pressure, Temperature Tracking CO 2 evolution what we can see Size = relative cost 1000 CSEM (Offshore only) InSAR Gravity (Onshore only) ution, m Vertical Resolu Surface-to- measurements Well-to- (Seismic, EM) In- measurements Microseismic (Onshore) 4D Seismic Areal Reservoir Coverage 9

10 What we can monitor? In boreholes From the surface CO 2 Saturation (neutron, density, resistivity, sonic) Sampling, downhole fluid analysis Cased Hole Formation Resistivity Pressure & Temperature Well Integrity (Cement, Corrosion) Electrical resistivity tomography (ERT) Microseismic X- seismic X- EM Distributed Temperature Sensing Tiltmeters 2D, 3D Seismic Microseismic Gravimetry (to back up time-lapse seismic) Echosounding, Seafloor samples Noble Gas Tracers MT (natural source plane wave electrical method) CSEM InSAR (Satellite Radar Imaging) CO 2 Saturation Measurement - Ketzin Contrast between formation water and CO 2 properties can be detected by neutron capture cross-section, hydrogen index, density, resistivity and sonic velocity to quantify the amount of free-phase CO 2 present in the pore volume. 625 m CO 2 presence over 4 week interval CO 2 Saturation ~ 60% in upper sand section (yellow). Little presence of CO 2 in lower sand No CO 2 above 625 m Well integrity risk: questions Site feasibility Site appraisal Are there any s on the potential storage site? Do we have access to the data? If yes, can we assess the current state of the s? What data do we need to acquire to assess/reduce the risk of leakage from s? What data do we need to satisfy regulatory requirements EU regulations state that risk of leakage from a potential storage site must be assessed before a storage licence can be granted. During operations, risk assessment drives site monitoring, post-closure and liability transfer plans. Concept selection Can we convert existing s to CO 2 injectors? Does any pose a risk of leakage during project life? If yes, how could the risk be managed/eliminated? Pitting Corrosion FDP What is the residual risk of leakage from the s? What remediation/contingency plans need to be in place during operations life? What monitoring plans will be implemented during injection? Cement Alteration 10

11 Wellbore Integrity Acoustic: imaging Mechanical: multi-finger caliper Isolation Scanner of the formation wall through casing and cement reveals hole enlargement Electromagnetic technology - Local application Cross- Electro-Magnetic A primary electromagnetic field is generated from a first, inducing currents in the formation and a secondary EM field, detected by receivers in the second. It has a limited resolution but could be used to track the CO 2 plume, possibly in conjunction with seismic methods. Remote sensing technology - InSAR Ground deformation monitoring using radar imaging by satellite. Interferometric synthetic aperture radar is a space borne geodetic tool used to obtain high spatial From Mathieson et al. GHGT9; 2008 resolution surface deformation maps. We can calculate the expected changes in surface elevation based on pressure changes and a 1D Mechanical Earth Model. This allows us to decide if a satellite acquisition will provide the required resolution (several mm). 11

12 Global measurements Time-lapse Seismic Gravimetry Sensitive to formation density CO 2 replacing water can be detected due to contrast between CO 2 and water Gravimeters are placed at the surface or downhole Sleipner 4D: Courtesy of Statoil InSAR Elevations determined from Synthetic Aperture Radar (SAR) images by interferometric methods. Uses two (microwave) antennas, displaced either vertically or horizontally, installed on the same satellite or aircraft platform. One of the antennas transmits the signal, but both receive it, resulting in two images being created. Magnetotelluric (MT) Measures the natural low-frequency electromagnetic field of the Earth Objectives of the monitoring plan - Summary Operational Injection operation control Wellhead pressure Bottom hole Pressure and Temperature Injection rate Microseismicity coses cty Quantification of injected CO 2 Mass flow Gas stream composition and phase Verification Well Integrity Annulus pressure Corrosion Cement Soil gas measurements Cap Rock / Fault Integrity Microseismicity Pressure interference Tracking the CO2 plume Geophysics techniques Pressure, Temperature Well logs (CO2 Saturation) Sampling Geodetic methods Assurance Impact: HSE monitoring Potable water quality Soils acidity Atmospheric concentration Surface deformation Detection of leaks/migration Sampling & chemical analysis Geophysics techniques Pressure interference Soil gas measurements Vegetation stress Eddy correlation tower Quantification of leaks Soil gas measurements Surface gas measurements Conclusion: as part of Minimizing Storage Risk Containment THE storage issue: Failure of sealing cap rock Permeable faults and fractures Migration along bores Risk reduction through: Choosing the right site Detailed reservoir characterization Comprehensive modelling Ongoing monitoring Risk mitigation through: Remediation methodologies Risk-based approach to project management Capacity Injectivity Containment : Different types of monitoring objectives Existing technologies and tools More work/research on the integration Closely related to Modelling 12