上吸式固定床热解气化新模型及其应用研究OA

To overcome the shortcomings of the existing models for updraft fixed bed pyrolysis and gasification process,i.e.,the excessive simplification of modeling and the absences of the characteristics of the reaction conditions and the temperature distribution law during the process of pyrolysis and gasification,a novel model for updraft fixed bed pyrolysis and gasification was developed.In the model,the temperature distribution law during the process of pyrolysis and gasification could be obtained,and it has a guiding role in the engineering design on pyrolysis equipment and system.By this model the influences of several key parameters on pyrolysis and gasification process were performed.It is found that with the increase of air equivalent ratio,the temperature of pyrolysis layer increases,and the average temperature of gasification layer and combustion layer increases first and then decreases.The concentrations of CO,H2 and CO2 in pyrolysis gas increases with the increase of air equivalent ratio,which increases the calorific value of pyrolysis gas.However,excessive air ratio will reduce the calorific value of pyrolysis gas due to the join of too much inert gas.The increase of moisture concentration of the incoming material results in a decrease of the outlet temperature of the furnace and a decrease of pyrolysis gas yield.The calorific value of pyrolysis gas is affected by the combine influence of moisture content and CH4 content in the pyrolysis gas.