GEOLOGIC SCREENING CRITERIA FOR SEQUESTRATION OF CO₂ IN COAL

Quantifying Potential of the Black Warrior Coalbed Methane Fairway, Alabama

A study sponsored by the

U.S. Department of Energy

National Energy Technology Laboratory

Project starting date: 10/6/00

Completion date: 10/6/03

Background

Sequestration of carbon dioxide in coal may be an economically viable environmental solution because it has potential to reduce greenhouse gas emissions while enhancing coalbed methane recovery. However, the sequestration capacity of coal basins has yet to be quantified, and geologic screening criteria need to be established to select sites favorable for demonstration and implementation of sequestration technology. With the support of the U.S. Department of Energy, Jim Walter Resources, Incorporated, and Alabama Power Company, researchers at the Geological Survey of Alabama and the University of Alabama have conducted a three-year study of the sequestration potential of the Black Warrior coalbed methane fairway, where two large coal-fired power plants operate adjacent to a thriving coalbed gas industry. The principal objectives of this 1.4 million dollar research project were to develop a geologic screening model that is transferable to the highly industrialized Carboniferous coal basins of eastern North America and Europe and to identify parts of the Black Warrior basin that are most favorable for the demonstration of carbon sequestration technology.

Geologic Factors

Experience from more than two decades of coalbed methane development provides a wealth of knowledge that can be used to quantify sequestration potential and develop a screening model. Indeed, the geologic variables controlling the distribution and producibility of coalbed methane resources are essentially the same as those determining carbon sequestration potential. These variables include stratigraphic architecture, structural geometry, hydrodynamics, geothermics, coal quality, gas content, and sorption capacity. The diverse types of data required to quantify sequestration potential have been managed using PC-based GIS and 3-D computer visualization packages. Also, a robust database of carbon dioxide, nitrogen, and methane isotherms and coal petrologic data has been assembled to improve understanding of the relationship of gas sorption to coal composition.

Screening Criteria

As sequestration capacity was quantified, a screening model was developed to identify areas favorable for demonstration and application of carbon sequestration technology. Geology, technology, and infrastructure are the main sets of variables that were used to develop the screening model. Critical geologic concerns are reservoir volume and continuity, sufficient permeability to accept large quantities of carbon dioxide, and seal integrity that will prevent leakage of injected gas. Emerging technologies to be considered are those associated with separation of carbon dioxide from flue gas, enhanced coalbed methane recovery, and mass sequestration of carbon dioxide independent of coalbed methane production. Proximity to power plants, pipeline systems, coalbed methane field design, and the locations of underground coal mines and their reserve areas are all elements of infrastructure that were incorporated into the screening model so that effective decisions can be made for the demonstration and implementation of carbon sequestration technology.

Technology Transfer

To ensure movement toward demonstration, commercialization, and widespread application of carbon sequestration technology in the Black Warrior CBM fairway, this project included a vigorous technology transfer program. An advisory committee consisting of the principal investigators, coalbed methane producers, and utility representatives was assembled. This committee helped guide the project and provided a forum for communication among the stakeholders who can implement demonstration and commercialization of carbon sequestration technology. Results have been and are being presented at technical meetings and workshops and are being published in journals and meeting proceedings. This web site is also central to technology transfer activities, and links to download reports are given below.

Click this link to view or download our Final Technical Report (PDF, 46.2 Mb). Most of the report can be printed on 8.5 x 11" paper. However, the report also incluces oversize plates that are best suited for printing on a large-format inkjet plotter.

Papers by the project team that were published in the proceedings of the 2003 International Coalbed Methane Symposium can be downloaded in PDF format from the following links:

Carroll, R. E., and Pashin, J. C., 2003, Relationship of sorption capacity to coal quality: CO₂ sequestration potential of coalbed methane reservoirs in the Black Warrior basin: Tuscaloosa, Alabama, University of Alabama College of Continuing Studies, 2003 International Coalbed Methane Symposium Proceedings, Paper 0317, 11 p. (2.4 Mb).

Groshong, R. H., Jr., Cox, M. H., Pashin, J. C., and McIntyre, M. R., 2003, Relationship between gas and water production and structure in southeastern Deerlick Creek coalbed methane field, Black Warrior basin, Alabama: Tuscaloosa, Alabama, University of Alabama College of Continuing Studies, 2003 International Coalbed Methane Symposium Proceedings, Paper 0306, 12 p. (1.2 Mb).

Guohai Jin, Pashin, J. C., and Payton, J. W., 2003, Application of discrete fracture network models to coalbed methane reservoirs of the Black Warrior basin: Tuscaloosa, Alabama, University of Alabama College of Continuing Studies, 2003 International Coalbed Methane Symposium Proceedings, Paper 0321, 13 p. (31.7 Mb).

McIntyre, M. R., Groshong, R. H., Jr., and Pashin, J. C., 2003, Structure of Cedar Cove and Peterson coalbed methane fields and correlation to gas and water production: Tuscaloosa, Alabama, University of Alabama College of Continuing Studies, 2003 International Coalbed Methane Symposium Proceedings, Paper 0312, 14 p. (1Mb).

Pashin, J. C., and McIntyre, M. R., 2003, Defining the supercritical phase window for CO₂ in coalbed methane reservoirs of the Black Warrior basin: implications for CO₂ sequestration and enhanced coalbed methane recovery: Tuscaloosa, Alabama, University of Alabama College of Continuing Studies, 2003 International Coalbed Methane Symposium Proceedings, Paper 0316, 12 p. (5.8 Mb).

Project Team

Jack C. Pashin (principal investigator)

Richard H. Groshong, Jr. (co-principal investigator)

Richard E. Carroll (coal geology)

J.Wayne Payton (petroleum geology)

Guohai Jin (structural geology)

R. Marc Bustin (coal petrology)

Marcella McIntyre (structural geology)

DOE Contracting Officer Representative

Dawn Chapman National Energy Technology Laboratory

Advisory Committee

Terry Burns, Geomet Operating Company

John Mark Goodman, Southern Company

Gary Hart, Southern Company

John Hollingshead Geomet Operating Company

Phil Malone, Geomet Operating Company

Paul Mock, ChevronTexaco

Jerry Saulsberry, Energen Resources Corporation

Rhonda Tinsley, Southern Company

Charles Willis, Black Warrior Methane Corporation

Links

State Oil and Gas Board of Alabama

Alabama Department of Environmental Management

American Association of Petroleum Geologists

American Petroleum Institute

Coalbed Methane Association of Alabama

DOE Carbon Sequestration Site

Petroleum Technology Transfer Council - E Gulf Reg.

Society of Petroleum Engineers

U.S. Geological Survey

Acknowledgment

This research was supported by the U.S. Department of Energy under cooperative agreement DE-FC26-00NT40927. Funding for this research includes $789,565 from the U.S. Department of Energy and $608,503 from non-federal sources. Any opinions, findings, conclusions, or recommendations expressed herein are those of the project team and do not necessarily reflect the views of the U.S. Department of Energy.