Carbon Sequestration Challenges in Kentucky

James A. Drahovzal, Brandon C. Nuttall, Stephen F. Greb, Thomas M. Parris, David C. Harris, and Cortland F. Eble
Kentucky Geological Survey, University of Kentucky, Lexington, KY

The State legislature of Kentucky recently passed legislation to provide incentives for coal-to-liquids and coal-to-gas facilities in Kentucky. The incentives include funding for the drilling of a deep research test well in each of the two Kentucky coal fields located in the Appalachian and the Illinois Basins. The goal of the two drill holes will be to provide detailed data critical for assessing the potential of specific reservoirs that are deeper than 2,500 feet for long-term CO₂ sequestration. In addition to the study of large-scale, “permanent” reservoirs, the legislation also calls for specific data collection with regard to the enhanced oil and gas recovery potential of existing Kentucky oil and gas fields. The challenge of this drilling program will lie in the selection of two sites that represent the complex and varied deep geology of the state, with broad applicability to the proposed facilities. Because coal-to-fuels facilities have lifetimes up to 40 years and will generate as much as 5 million tonnes of CO₂ each year, massive reservoir capacities will be required. Although Kentucky has projected an estimated 7.2 billion tonnes of geologic capacity in deep saline aquifers and oil and gas fields, the details of reservoir- and seal-rock parameters, such as porosity, permeability, injectivity, capillary entry pressure, and degree of fracturing at depth, remain largely unknown. An additional 25 billion tonnes of storage may be available in organic-rich shales by means of adsorption of CO₂, but this is speculative and requires confirmation. Data collected from the drilling and analyses of the two wells will help to inform decision makers about the viability of future development of the proposed facilities in Kentucky. Such facilities are important to the future economy and use of coal in the Commonwealth, as well as to that of the Nation.

AAPG Search and Discover Article #90078©2008 AAPG Annual Convention, San Antonio, Texas