Abstract
Development of clean coal technology is highly envisaged to mitigate the CO2 emission level while meeting the rising global energy demands which require highly efficient and economically compelling technology. Integrated gasification combined cycle (IGCC) with carbon capture and storage (CCS) system is highly efficient and cleaner compared to the conventional coal-fired power plant. In this study, an alternative process scheme for IGCC system has been proposed, which encompasses the recycling and re-use of CO2 from the flue gas of gas turbine into a secondary syngas processing route, proceeding with conversion of syngas into methanol. The system modification requires extensive mass and energy integration strategies to ensure that the efficiency and economics of the system are achieved to a considerably high level. The thermodynamic and economic feasibilities of the modified IGCC system were found to attain tremendous improvements. The thermal efficiency has been increased from 54% to 89.3%, whilst the economic potential has been enhanced from 48.1 M€/y to 377.4 M€/y. These results have shown good future prospects for employing CO2 re-use technology into IGCC system, as an alternative to CCS system.