THE POTENTIAL FOR CARBON SEQUESTRATION IN COAL BEDS IN THE NORTHERN AND PARTS OF THE CENTRAL APPALACHIAN BASIN

The Midwest Regional Carbon Sequestration Partnership (MRCSP), one of seven regional CO₂. sequestration partnerships funded by the U.S. Department of Energy, is investigating the potential for future carbon capture, storage, and sequestration. One potential option being studied is the sequestration of CO₂. into “unmineable” coal beds in eastern Kentucky, Maryland, Ohio, Pennsylvania, and northern West Virginia. It is believed the CO₂. would adsorb onto the coal while displacing naturally occurring methane, which in turn, could be recovered as a fuel. Although there is currently only limited production of coalbed methane in the MRCSP part of the Appalachian basin, this sequestration method could provide an economic incentive for offsetting some of the associated costs of sequestration. The criteria used to assess the sequestration potential of coal beds in the MRCSP region include determining the cumulative thickness of coal beds at least 1 foot thick and more than 500 feet below drainage. Data were from deep coal exploration tests, and oil and gas exploration density logs. The 500-foot limit is an estimate of the maximum depth of surface fracturing based on mining regulations. Results indicate large areas with more than 30 ft of cumulative coal thickness along the northern Appalachian basin axis in southern Pennsylvania, southeastern Ohio, and northern West Virginia that are estimated to have a storage potential of 0.2 to 0.3 gigatonnes of CO₂.

Although there is significant potential in the basin, how much of this resource is truly “unmineable” and available for future storage is problematic and varies with geologic, economic, environmental, regulatory, and political considerations. As energy costs increase, new technology and increasing coal demand may significantly change the definition of “unmineable” in the future.