煤部分气化燃烧集成系统最优化模型及其求解

FOUNDSTION AND CALCULATION OF THE OPTIMUM MODEL OF COAL PARTIALLY GASIFICATION AND COMBUSTION SYSTEM

运用已有的基础动力学数据 ,将流化床气化过程用全混流模型描述 ,同时认为部分气化煤焦的燃烧速率相当快 ,其产生的电能只与燃烧的炭量成线性关系 ,不受其他因素的影响 .在此简化条件的基础上建立了一个部分气化、燃烧集成优化的经济评价模型 .通过对模型的模拟计算发现 :煤部分气化、燃烧集成优化是可行的 ,采用这一集成技术在提高煤炭利用率的同时 ,也可提高经济效益 ;1 0 0 0℃时 ,三种煤的最优气化率在 60 %～ 80 %之间 ,活性好的神木煤其最优部分气化率最高 ;提高气化温度 ,可以提高煤焦最优气化率 ,从而可提高总体经济效益 .

There is an increasing interest in process integration concept such as the combination of coal partial gasification and combustion for the gas making and power or heat generating throughout the world.In this paper,a model for the optimum system is set up on the basis of simplifying models of fluidized bed gasification and the partially gasified char combustion.According to the calculation results,the conclusions can be reached that the combination of coal gasification and combustion is desirable which can improve not only the utilization efficiency of coal,but also the economic benefit.At temperature of 1 000 ℃ ,the optimum gasification conversion of three coals is in the range of 60 % to 80 %.The optimum gasification conversion of high reactivity coal is larger than that of low reactivity coal.Within the limits permitted by reactor temperature,increasing gasification temperature can improve optimum gasification conversion rate and the economic benefit.