水煤浆气流床气化炉的数值模拟

摘要

A one-dimensional steady-state mathematical model for coal slurry-fed gasifiers was developed by incorporating entrained-flow bed configuration, coal properties, chemical reactions, and heat and mass transfers within the gasifier. The external shell temperature was used as the heat transfer boundary condition, and an implicit variable step-size method was used to solve the momentum, heat and mass transfer ODEs considered in the model. Huating coal, Australia/UBE coal, Illinois no.6 coal and Eastern coal were used as examples to validate the model. The calculated results were in good agreement with the literature data. The relationship between the gasifier size and gaseous compositions, particle residence time, and carbon conversion rate was discussed using a GE gasifier with feedstock of 750 tons of Huating coal per day, and the developed model could be helpful to design and operate slurry-fed gasifiers.%根据气流床结构、煤的物性、气化过程化学反应及传热传质的特点，以气化炉外壁温度等为边界条件，建立了水煤浆气化炉的一维稳态数学模型，采用隐式变步长ODE算法平行求解气化过程中涉及的动量、传热、传质等常微分方程组。并以华亭煤、Australia/UBE、Illinois no.6以及Eastern coal四种煤为例进行了验证，所得模型计算结果与文献试验数据能够较好地吻合。在此基础上以750t/d的GE炉为例，讨论了华亭煤气化过程中的组分变化、颗粒停留时间及碳转化率与气化炉尺寸的关系。所建模型对气化炉设计及运行有一定的指导意义。