基于遗传算法-综合计算法的生物质热解气化优化分析

Analysis and optimization of biomass pyrolysis and gasification based on genetic algorithm-comprehensive calculation method

生物质热解气化可实现碳基可再生能源的高效清洁利用。为准确预测生物质热解气化产率分布,贴合生物质热解气化真实转化过程,由生物质热解气化实测数据通过遗传算法(genetic algorithm,GA)对综合计算法模型进行改进,按照综合计算法中热解段和固定碳气化反应段建立Aspen Plus模型。结果表明:在GA-综合计算法中,稻壳在热解段CO_(2)的氧为干基氧含量的32.02%,焦油产率为挥发分的8.32%,平均热解组分误差为8.53%,平均合成气组分误差为5.37%;基于GA-综合计算法的Aspen Plus模型,热解过程组分和气化段固定碳转化率由GA-综合计算法得出,实现了GA-综合计算法和流程模拟的复合,其合成气模拟值与实验值接近,较好地反映生物质热解气化流程,为生物质热解气化产率分布及流程参数优化提供指导。

Biomass pyrolysis and gasification can realize the efficient and clean utilization of carbon-based renewable energy.In order to predict yield distribution of compositions and achieve the closest of biomass pyrolysis and gasification,the comprehensive calculation method has been improved through genetic algorithm(GA)method with tested data of biomass pyrolysis and gasification.Aspen Plus model has been established consisting of pyrolysis stage and gasification reactions of fixed carbon according to GA-comprehensive calculation method.The results show that the optimum ratio coefficient of O for husk(dry basis)transferring to CO_(2) equals 32.02%in the GA comprehensive calculation method,and the optimized yield ratio for tar(Rtar)is 8.32%of the volatile with the mean pyrolysis component error of 8.53%,while the mean gasification component error of 5.37%.As for Aspen Plus model based on GA-comprehensive calculation method,the yield distribution of gasification components and conversion rate of fixed carbon in gasification process are calculated by GA-comprehensive calculation method,enhancing the computing reliability through the combination of theoretical calculation and process simulation.The simulation values of gasification gas compositions have good agreement with experimental values,which reveals pyrolysis stage and gasification process clearly.Generally,the proposed innovative model contributes to the prediction of component distribution of biomass pyrolysis and gasification,along with parameters optimization of gasification system.