Optimization Of Reaction Kinetic Parameters In The Simulation Of Entrained Flow Gasification Of Coal

As a prosperous clean coal technology with high efficiency and low pollutionin the future, coal gasification technology has gradually been brought to theattention of the major coal countries both at home and abroad. To some extent, thehigh cost and complicated system of the pressurized gasification test-bed restrictcarrying out experimental study for the entrained flow gasification. Therefore,numerical simulation has been widely used for the study of coal gasificationprocess.Paying attention to the difficulty in selecting kinetic parameters in thenumerical simulation process and the obvious influence of pyrolysis model for thecalculation results, the study in this paper optimizes the kinetic parameters andpyrolysis model of coal gasification process based on FLUENT. First, the suitablechemical reaction model for the research object in this paper will be selectedthrough calculation. Then the pyrolysis model will be modified with the results ofpyrolysis experiments and the kinetic parameters of gas-solid two opposite reactionand unknown parameters of pyrolysis model will be optimized and oxygen to carbonatomic ratio will be selected through calculation. Finally the optimized calculationresults will be compared with those of traditional gasifier.Results of pyrolysis experiments show that with the increase of pyrolysispressure, the content of CH4gradually increases in the pyrolysis gas, content of COgradually reduces in the pyrolysis gas, and loss of weight gradually decreases at thesame pyrolysis temperature. Results of simulation numerical of coal gasificationshow that the results of numerical simulation are more reasonable with the use ofspecies transport model for the research object of the paper. Through optimizationcalculation, the suitable kinetic parameters for the research object of the paper hasbeen obtained and the optimal values of unknown parameters for the pyrolysismodel are determined and the suitable oxygen to carbon atomic ratio is selectedthrough calculation. By comparing numerical simulation result of dry pulverizedcoal gasification and coal-water slurry gasification before and after the optimizationwith the actual operation value of traditional gasifier, the paper finds that theoptimized calculation results are closer to the actual operation value of traditionalgasifier. The results indicate that with the use of the optimized parameters of themodel for numerical simulation of the gasifier, the actual gasification status of thegasifier can be reflected.