Energy, Vol.119, 1171-1180, 2017
A thermodynamic and environmental performance of in-situ gasification of chemical looping combustion for power generation using ilmenite with different coals and comparison with other coal driven power technologies for CO2 capture
Chemical looping combustion (CLC), as "next-generation" CCS, is suggested as the most promising candidate for a long-term implementation of carbon capture. This study is aimed to examine both thermodynamic and environmental performances of ilmenite-based in-situ gasification chemical looping combustion (iG-CLC) power plant with different coals. Besides, comparison with already-achievable coal feed plants are involved. Thermodynamically, lower oxygen carrier to fuel ratio (Phi) is more feasible to obtain autothermal operation in high-rank coal-feed iG-CLC plant. Anthracite-feed iG-CLC power plant obtains the highest net electricity efficiency (46.0%). Approximately more than 10% net electricity efficiency benefits are earned in an iG-CLC power plant (anthracite-based case) compared with that in conventional plants. From environmental aspect, CO2 emission rates for lignite-feed iG-CLC plant amount to be the highest, i.e. 103.05 kg/MW h vs. the lowest bituminous-based case (91.94 kg/MW h). Due to the higher CO and sulfur compounds concentration, the captured CO2 stream in an iG-CLC plant may not be qualified for direct transport, and further pre-transport treatment is required. For anthracite-feed iG-CLC power station, the net NO emission rate ranks the highest (4.14 kg/MW h). By contrast, it has been reduced by 0.07 kg/MW h and 0.28 kg/MW for bituminous and lignite-feed case, respectively. (C) 2016 Elsevier Ltd. All rights reserved.