The Transition of CO2-EOR to Storage

Many O&G technical disciplines, particularly enhanced oil recovery by CO2, are needed for CO2 storage (CCS). However, important differences exist between CO2 injection performance expectations for EOR and CO2 management associated with long-term storage. This new CO2-EOR-to-CCS course will examine these differences to discover the current practical potential of EOR for CO2 storage, and to understand where EOR can be used to store CO2.

Target Audience

The 5-day course is designed for petroleum engineers, geologists, geophysicists, and subsurface professionals. Having several disciplines in the course will make the course meaningful and applicable to all.

You Will Learn

• Role of CO2-EOR (CCUS) and CCS in net zero and decarbonization
• A review of sources of CO2
• Enhanced oil recovery overview; trapping mechanisms in the reservoir, trapping by caprock seals
• An understanding of the CO2 – EOR process; particular the factors that affect volumetric sweep efficiency
• Simple capacity estimates for CO2 storage
• Impact of gravity on CO2 storage and oil recovery
• The tradeoffs between vertical vs. horizontal wells
• EOR and storage in conventional and unconventional reservoirs
• Geochemical reactions, salting effects, and other mechanisms impacting CO2 injectivity for CCS
• Lab- and field-scale examples of EOR and CCS
• Monitoring, verification, and reporting practices in CCS

Course Content

Day 1: Introduction and Basic Fluid Properties

Non-lecture time: (lunch break, 15 min break for every 1 hr of lecture, Q/A sessions, class assignments)

Motivation for this course 

• Global climate change
• Greenhouse gas effects
• The sources of CO2 and an overview of capture technologies
• Modes of storage: oil reservoirs (EOR), gas reservoirs (EGR), saline aquifers, conventional and unconventional reservoirs

Basic fluid Properties of CO2, Water, and Methane 

• Density
• Viscosity
• Water solubility
• Interfacial tension
• Examples of lab tests

Petrophysical Properties 

• Permeability/porosity
• Contact angle/Wettability
• Capillary pressure and j-Leverett
• Relative permeability and hysteresis (capillary trapping)
  • CO2/water
  • CO2/oil/water
• Examples of Lab tests

Phase Behavior

• Basic phase behavior diagrams
• Solubility in brine as a function of T, P, and salinity
• Miscibility with oil (MMP)
• Miscible CO2/Methane
• Impacts of CO2 impurity on EOR and storage projects
• Dispersion/diffusion basics

 

Day 2: Reservoir Engineering Fundamentals and Storage Options

Flow and Sweep 

• Pressure build-up
• Sweep efficiencies
• Well design (vertical vs. horizontal)

Heterogeneity Measures

• Dykstra-Parsons coefficient
• Flow capacity curves
• Lorenz coefficient
• Koval
• Examples of numerical simulations

CO2 Storage Options

• Oil reservoirs
• Gas reservoirs
• Saline aquifers
• Status of EOR/EGR and storage in shale gas and shale oil with hydraulically fractured wells

CO2 Trapping Mechanisms 

• Structural
• Capillary
• Brine dissolution
• Mineralization

Carbonate vs. Sandstone Reservoirs 

• Geochemical reactions (dissolution/precipitation),
• Water vaporization salting
• Injectivity

Exercise: Key factors affecting storage in dry gas reservoirs, aquifers, and EOR reservoirs

 

Day 3: Storage Options

Storage in Saline Aquifers 

• Buoyancy effects
• Storage capacity
• Pressure management
• Enhanced mineralization
• CO2 inventory

Lab and Field Test Examples 

• Review of typical lab tests
• Field case studies and challenges
  • Caprock integrity
  • Leaky wells
  • Cement integrity
  • CO2 purity
  • Water

Modeling and CO2 Monitoring 

• Numerical examples and key features for CCS in aquifers
• Monitoring, verification, and reporting practices in CCS

Storage in Depleted Gas Reservoirs

• CO2 storage and methane production vs. storage project
• Diffusion/dispersion and impact on sweep, storage capacity, and gas purity
• Hydrate formation and mitigation

 

Day 4: Storage in Gas and Oil Reservoirs (Miscible and Immiscible)

Displacement flow regimes and dimensionless groups

• Buoyancy. (buoyancy number)
• Heterogeneity (Dykstra-Parsons coefficient)
• Channeling (Koval number)
• Dispersive (Peclet number)
• Fingering (mobility ratio)

Storage in Gas Reservoirs 

• Examples of lab tests
• Example of field cases
• Numerical simulation challenges

Storage in Shale and Tight Oil Reservoir 

• Storage mechanisms
• Hydraulic fractured wells
• Lab tests

Storage in Oil Reservoirs 

• CO2 storage and oil recovery mechanisms
• Miscible vs. immiscible floods
• Net CO2 storage calculations and ways to delay CO2 breakthrough
  • WAG
  • Foam
  • Other conformance methods

Exercise: Miscibility types and MMP determination (MMP correlations, EOS methods overview)

 

Day 5: Storage in CO2-EOR

Review of Field Cases

• Interwell, patterns, Huff&Puff
• CO2 inventory
• Utilization factor

Exercise: Recovery factor correlation for Huff&Puff CO2-EOR

High-Level Economics 

Facility Consideration 

• Well Integrity
• CO2 Purity/Source/Transport
• Source and composition of water for WAG

Conclusions/Review/Q/A/Evaluation

Product Details