Technological solutions for an advanced IGCC plant

Abstract

The paper studies the basic methods offered by different sources for raising the efficiency of the air-blown integrated gasification combined cycle (IGCC). The technological solutions that can minimise the efficiency gap between IGCC and natural gas combined cycle (NGCC) were selected. The flow diagram for an air-blown IGCC is proposed which ensures cycle efficiency and exceeds that of O2-blown IGCC owing to a decreased need for fuel gas. The proposed scheme would enable the approximation of the cycle efficiency to NGCC. The role of integration linkages in raising the efficiency of IGCC was also assessed. Thermodynamic models for the basic elements of IGCC were developed. We calculated the efficiency of steam-air blast and cycle air heating during cold fuel syngas clean-up using IGCC with an M 701F4 gas turbine that runs on syngas processed from Kuznetsk bituminous coal as a model. We also established that steam-air blast heating increases the heat value of fuel gas by 10%, conversion efficiency by 84.2%, and gross/net efficiency of IGCC by 0.44/0.53%. Steam-air blast and cycle air heating decreased coal consumption for gasification by 44% and led to an additional increase in gross/net efficiency by 0.77/1.06%. The solutions proposed in the paper enable the creation of a flowchart for IGCC with F-class gas turbine and one gasifier with a capacity of 2000 t/d for coal and gross/net efficiency of 52.47/50.64%.