Integrated Subsurface Carbon Sequestration and Enhanced Coalbed Natural Gas Recovery Using Cement Kiln Emissions, Wilson County, Kansas

Kansas Geological Survey

KGS Open-file 2006-13


Coal Rank and Gas Generation

Rank, or a coal’s thermal maturity, is an important control on the gas generation and final gas content of a coal. During the coalification of peat and the continued thermal maturation processes of coal, the total amount of gas generated increases. Coals are unique in that they are not only the source of the gas but also the reservoir. At a particular point in the maturation process, coals lose their capacity to store gas. Maximum gas contents can be found in high-volatile A and B bituminous coals. Further maturation beyond this point will lead to compaction of the pore spaces in which gas is stored. It is important to recognize coal rank in estimating potential maximum gas content and storage capacity for a CO2 injection.

Last Modified May 2006