Publications

CO2 injection into coal seams is a very attractive option for geological storage, since CO2 is readily adsorbed by the coal. At the same time, the injected CO2 displaces adsorbed methane from the coals internal surface. Consequently, injection of CO2 into a coal bed can enhance the recovery of coal bed methane (ECBM). In order to explore this potential, adsorption experiments were conducted on coal samples from South Sumatra Basin and Kutai Basin. These two basins are the main coal producers in Indonesia. The coal samples cover maturity ranges from subbituminous to high volatile bituminous rank with 0.42% to 0.66% vitrinite reflectance. The study has provided early experimental data for CO2 adsorption capacity using a volumetric method and examines the effects of moisture, grain size, and ash content, as well as rank effects on Langmuir parameters. Comparison of high-pressure adsorption experiments on supercritical CO2 yielded significant results compared to the low-pressure adsorption experiment. The Langmuir parameters in the coal samples covered from 1.773-2.932 mmol/g for VL as well as 5.353-16.021 MPa for PL, respectively. Based on numerical simulations, CBM production rates are significantly increased by CO2 injection.