Energy Chemical Engineering (Topic Field) Simulation for Influence of High Pressure on Release of Inorganic Species during Combustion of Pakistani Coal

Abstract

The inorganic species are highly volatile, released during thermal conversion process and especially at high pressure combustion leads to several problems of fouling, slagging and corrosion when they reach the colder part of plant. The comprehensive knowledge of release alkali species Na-,K-,Cl and S-species is required prior to carry out experiment. Therefore thermodynamic equilibrium calculations were performed by Fact Sage 5.2 and simulated the combustion environment at elevated pressure. Three soft Pakistani coal such as Lakhra (Vad < 41.44%), Thar (Vad < 42.02%) and Sor-range ((Vad < 21.11%) belong to Lignite and sub-bituminous coal were selected and releasing order was calculated by plotting mole fraction of each species VS pressure (5 to 15bar ) at 1000°C. On the basis of predicted releasing order the SO2 can be predicted most stable species under combustion at elevated pressure. The high released amount of SO2, H2S, NaCl, KCl and HCl was predicted for LKH, THC and SRC at 5 and 15 bar pressure and 1000°C temperature.Comparing with high pressure the predicted released of SO2 was found higher than H2S, NaCl, KCl and HCl at 5 bar pressure while the released of H2S was observed lower than SO2, NaCl, KCl and HCl at 15 bar pressure during combustion process. The above available predicted information is valuable for hot gas cleaning technology.