Kinetics of steam and CO_2 gasification with high ash fusion temperature coal char under elevated pressure

摘要

A high ash fusion temperature (AFT) coal char was gasified with steam and CO2 under elevated pressure in a modified pressurized thermogravimetric analyzer. The ambient pressure varied from 0.5 MPa to 3 MPa. It was found that activation energy E-a (char-CO2 reaction) was from 214.19 kJ/mol to 240.35 kJ/mol, and activation energy Ea (char-steam reaction) was from 170.02 kJ/mol to 174.02 kiimol by using shrinking core model. The factor of partial pressure influence (n) was 0.44 and 0.54 for CO2 and steam gasification, respectively. The results proved that the high AFT coal (U coal) has poor gasification reactivity by comparing with other research and provided complete kinetic data for developing the entrained flow gasification technology using high AFT coal