A Review Summary on Multiple Aspects of Coal Seam Sequestration

Presence of natural gas in adsorbed form in coal seams is the primary reason for scientists to attempt CO2 sequestration in the same. The economic analysis states that the additional methane in case of coupled enhanced coalbed methane recovery (ECBMR) with sequestration partly offsets the cost of the operation. Injected CO2 reduces the partial pressure of methane and enhances its desorption from the matrix. Furthermore, CO2 is preferentially adsorbed onto the porous surface of the coal thereby displacing methane from adsorption sites. Apart from estimation of coal gas reserves, several technical parameters related to the adsorption capacity of coals and suitable trapping/sealing mechanism must be ensured before utilizing coal as a CO2 sink.