Impact of coal quality and gasifier technology on IGCC performance

摘要

Integrated coal gasification combined cycle (IGCC) plants with pre-combustion capture of CO_2 represent one of the most promising options for power generation with carbon capture and storage. This work investigates to what extent IGCC performance (with and without CO_2 capture) is affected by coal quality for two different entrained flow slagging gasifiers. Based on an IGCC model developed in Aspen Plus and combined with GTPRO, mass and energy balances were computed. Two gasification technologies were considered: A dry feed gasifier with syngas heat recovery which represents the Shell technology, and a slurry feed gasifier with full water quench which represents the GE technology. For each gasifier, five different coals were used and alternatives with and without CO_2 capture calculated. It was found that the thermal efficiency, CO_2 emissions and net power output of the slurry feed IGCC was strongly dependent on coal type, and had lowest performance for low rank coals. On the other hand, the dry feed IGCC was little affected by coal type. The slurry feed IGCC performed closest to the dry feed IGCC when CO_2 was captured and the two highest rank bituminous coals were used.