Masterclass on Carbon Capture and Storage (CCS)

Day 1 : Overview

Introductions and Context

• Background on CCS and its role in reducing greenhouse gas emissions, with an exercise on changing greenhouse gas sources in developed nations.
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Geological Storage Options

• Overview of CCS history, types of projects, and extend of need to scale up CCS, with a related exercise.

Evidence and Projects

• Insights into CO2-EOR, saline aquifer CCS, hub and cluster plans, and typical injection rates.
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CO2 Properties and Storage

• Phase behavior, trapping mechanisms, and storage quantification in saline aquifers vs. depleted gas fields, with an exercise on phase and depth effects

Day 2 

Storage Efficiency

• Factors influencing CO2 trapping, including viscosity, buoyancy, and plume radius, with a comparison of efficiency in gas fields vs. saline aquifers. Exercise on storage efficiency influenced by (i) fluid viscosity and (ii) gravity effects.

CO2 Injectivity

• Key role of permeability in injection rates, controls on permeability, and an exercise predicting injection rates

Relative Permeability

• Impact on CO2 flow, formation damage, and intraformational baffles, with an exercise on predicting effect of formation damage on injection rates.

Geomechanical Aspects

Effects of high-pressure CO2 on stresses, fault failure, and intact rock behavior in saline aquifers and gas fields. Exercise on safe maximum CO2 injection pressure and thus injection rates.

Mineral Dissolution Processes

Mechanisms, extent, and evidence of dissolution, and its effects on storage and injection rates. 

Case study and exercise: The range effects of dissolution on CO2 storage and injection rate.

Day 3 

Mineral Precipitation Processes 

• Causes, controls, and likely extent of mineral precipitation during CO2 injection, including halite in saline aquifers and rapid mineral sequestration in basalts.

Top-Seal Attributes

• Mudstone porosity, geochemistry, and effects of CO2, with an exercise on calculating maximum safe CO2 column height.

Leakage Risks

• CO2 diffusion and advection through top-seals, leakage via wells, and interaction with well materials. Exercise on predicting potential leakage rates from saline aquifers.

Geomechanical Issues

• Fault behaviour under CO2 pressure, fault reactivation risks, and fracturing evidence. Exercise on predicting uplift from CO2 injection.

Monitoring CO2 Injection

Purposes, methods, costs, and regulatory requirements, with a focus on risk assessment using immediacy versus severity matrices.

Case study and synthesis comparing the successful Sleipner (Norway) and the terminated In Salah (Algeria) CCS projects in terms of perception of leakage risk

During this course, you will

• Explore the role of geoscience in CCS and its impact on CO2 emissions reduction.
• Examine past CO2 injection projects and their differences from industrial-scale CCS.
• Understand CO2 behaviour in the subsurface, including injection pressures and stress regimes.
• Learn about CO2 storage capacities, from pore-scale to aquifer volumes.
• Analyse factors influencing CO2 flow, including permeability and aquifer architecture.
• Investigate the effects of CO2 on host aquifers, from geomechanical to geochemical impacts.
• Assess seal integrity and risks, from fracking to induced seismicity and leakage.
• Explore strategies for monitoring and ensuring safe, long-term CO2 storage.
• Compare CCS in saline aquifers versus depleted gas fields.