Investigation of air-blown two-stage entrained-flow gasification of micronized coal

Abstract The aim of this work was to intensify the air-blown conversion of coarse grinding coal into the fuel syngas by means of mechanical activation of some part of the coal without the involvement of other methods of conversion intensification (oxygen enrichment of blast, heating of blast or fuel, etc.). Experimental studies were carried out at the Institute of Thermophysics of the Siberian Branch of the Russian Academy of Sciences (IT SB RAS) using special setup with the two-stage coal and air input. We have performed a comprehensive experimental and computational study of air-blown gasification of coarse coal (Gcoal2) by combustion products of micronized coal (Gcoal1) at the ratio of primary and secondary coal gc = Gcoal1/Gcoal2 = 0.82–0.39 (90/110–90/230 kg/kg), stoichiometric factor α = 1.39–0.51 and the temperature in the flame from 1.200 to 1.300 to 1.500–1.600 °C. It has been found that micronization of primary coal allows maintaining a stable autothermal mode of air-blown gasification of coarse bituminous coal without involving the additional methods of conversion intensification at α = 0.5. The CFD simulation based on experiments determined the conditions for implementation of the investigated process.