Estimation of performance variation of future generation IGCC with coal quality and gasification process - Simulation results of EU H2-IGCC project

摘要

The integrated gasification combined cycle (IGCC) power plant delivers environmentally benign power from coal. The overall objective of the European Union (EU)'s H_2-IGCC project is to develop and demonstrate technological solutions for future generation IGCC plants with carbon capture. As a part of the general goal, this study evaluates the effects of coal quality and the selection of gasifiers on the overall performance of the baseline configuration of the IGCC plant. Four commercially available gasifiers i.e., Shell, GE, Siemens, and ConocoPhillips gasifiers are considered for this comparative study. The effects of three different types of coals on the gasification processes have been investigated, as well as the overall performance of the plant. Simulation results show that slurry-fed gasifiers are not suitable for lignite coal, while dry-fed gasifiers are less sensitive to coal quality. Coal quality has the greatest effect on the GE gas-ifier. The ConocoPhillips gasifier demonstrates the highest cold gas efficiency using bituminous coal. The coal rank and the gasification process have relatively less effect on gas turbine power output, while steam turbine power output varies significantly with these. Although steam turbine power output increases with a reduction in coal quality, especially for slurry-fed gasifiers, the air separation unit power demand offsets this increase. The highest overall plant efficiency is 37.6% (LHV basis) for the GE gasifier and coal B. The lowest overall efficiency penalty with coal quality is 5% (LHV basis) for the Shell gasifier with input changed from bituminous to lignite. Moreover, simulation results show that GE's gasification technology has the highest CO_2 emissions for lignite coal, i.e. 158 g/kWh.