CO2-Oxy underground coal gasification integrated proton exchange membrane fuel cell operating in a chemical looping mode of reforming

O2/CO2 based underground coal gasification (UCG) is a promising clean coal technology for the exploitation of deep underground coal resources with a minimal difficulty of the operation. However, the generated syngas of the underground is enriched with carbon monoxide and it should be converted into a clean gas on the above ground for the end use. In the present study, a clean mode of power generation is proposed using the CO enriched UCG syngas. Firstly, the UCG gas is reformed into pure hydrogen using chemical looping reforming (CLR) method. Secondly, the pure hydrogen obtained from CLR process is used suitably to generate electric power in a proton exchange membrane fuel cell (PEMFC) system. Hence, carbon energy is converted into hydrogen energy through the CLR technique and this clean gas is efficiently transformed into electrical energy using the PEMFC system. A net efficiency for converting CO enriched gas into H2 through conventional system using water gas shifting reactors is evaluated and compared with the CLR system. An energy analysis of O2/CO2 based UCG integrated with CLR-PEMFC shows 43.6% net efficiency with carbon capture and storage (CCS).