Stochastic Modeling Of Entrained Flow Gasification Process And Optimization Of Operation Parameters

In the process of coal gasification,the influence of noise factors such as coal moisture,ash content and coal feeding speed on gas production performance cannot be ignored,and the instability of these factors will lead to the decline of gas production quality.Therefore,considering the unstable factors in the process of coal gasification,this paper optimizes the operation parameters in the process of coal gasification to achieve the purpose of optimizing the gas production index.In order to get the relationship between operation parameters and gas production indexes,this paper first uses Aspen Plus software to carry out simulation experiments,and establishes a neural network model based on the experimental data.Three operation parameters,oxygen coal ratio,steam coal ratio,pressure,as well as the relationship between the three noise factors of ash content,moisture content and coal feeding speed,and the two gas production indexes of effective gas production volume fraction and cold gas efficiency,are obtained.However,there is also a key parameter operating temperature that can’t be adjusted in Aspen Plus,so in order to obtain the optimal operating temperature,the ash melting point,which plays a decisive role,is studied in this paper.In this paper,the dynamic sequence of coal ash melting point is simulated by Markov method,and the simulation effect is good.Based on the relationship between the melting point of coal ash and the operating temperature,a stochastic optimization model of operating temperature based on Markov process is established,and the optimal operating temperature is obtained by genetic algorithm.In addition,in order to optimize the three operating parameters of oxygen coal ratio,steam coal ratio and pressure,a stochastic differential equation model is established as the constraint condition,and a stochastic optimization model of coal gasification process is established with the maximum gas production index as the objective function.Finally,the model is optimized by NSGAII algorithm,and the optimal operating parameters are obtained.Finally,the optimization results of four operation parameters,oxygen coal ratio,steam coal ratio,pressure and operating temperature,are determined,so as to provide reliable reference for actual production.