Basic Research On Main Influence Factors Of Pulverized Coal Fast Pyrolysis

The dissertation is designed on the basis of the background research of thepulverized coal utilization, the suspended reactor of high solid-gas ratio technology wasintroduced into coal pyrolysis process with the purpose of increasing the reaction rate,reducing the reaction time, improving coal tar yield, which provided a theoretical basisfor the suspended reactor of high solid-gas ratio technology used in the pulverized coalfast pyrolysis technology.Low metamorphic pulverized from Yulin coal was selected as a raw material, coalfast pyrolysis were studied using thermogravimetric analyzer and coal pyrolysisexperiment platform. The studies included as followings:（1） The effect of heating rate, reaction temperature, catalyst type and catalystmixed quantity on weight loss rate from the Yulin pulverized coal pyrolysis processwere studied by thermogravimetric analyzer. And the kinetics of pulverized coalpyrolysis were studied using the distributed activation energy model. The results showthat the temperature of maximum rate of pulverized coal weight loss is in creased withthe heating rate enhanced; the weight loss rate of the pulverized coal pyrolysis graduallyincreased with the increase of temperature, and the weight loss rate at the higherpyrolysis temperature increased slowly; Fe₂O₃and TiO₂could improve the weight lossrate of coal pyrolysis, the weight loss rate of coal pyrolysis increased with the increasedof catalyst addition. The results of kinetics study showed that the kinetic model couldwell explained the thermodynamic curves, the activation energy in coal pyrolysis reaction can be effectively reduced bythe Fe₂O₃addition, which indicates that the coalpyrolysis reaction could proceeding more easily when Fe₂O₃was used as catalyst.（2） The effect of operating parameters on the product yield during Yulin pulverizedcoal pyrolysis were studied by the fixed-bed experimental platform in this article. Theeffect of catalysts on the the yield of product from hydrogenation pyrolysis process ofYulin pulverized coal was researched. The results show that the tar yield of pulverizedcoal pyrolysis increased with the heating rate increasing, and the maximum tar yieldcould reached15.71%when the coal particle size of pulverized was0.08-0.105mm andthe final temperature was600℃；the proper particle size at which the maximum valueof tar yield obtained moved from the micron to millimeter. The gas and tar yield of coalfast hydrogenation pyrolysis process at low temperature have be improved with thecatalyst mixed, the CaO and MnO₂could significantly improved the yield of gases fromcoal pyrolysis, and the Fe₂O₃could increase tar yield of pulverized coal pyrolysisprocess.In this dissertation, the theoretical and experimental research of pulverized coalpyrolysis technology, which lays a theoretical foundation for the research on pulverizedcoal fast pyrolysis.