主吸收塔整体热处理遗传算法优化及全流程研究

Research on optimization and whole process of heat treatment of main absorber by genetic algorithm

为明确主吸收塔热处理作用效果,研究塔壁温度分布及传热特性,以主吸收塔为对象建立热-流耦合模型,对热处理中升温-保温-降温全流程进行数值模拟。提出升温均匀度概念,结合多目标遗传优化算法,分析热处理时入口烟气参数对升温均匀度的影响,得出最优化热处理工艺技术。结果表明:热处理时壁面高温区与低温区分别位于封头及人孔处,升温速率和壁面温差与火焰高度、外焰面角度正相关;升温速率与烟气流速正相关,温差随着烟气流速先减小后增大。热处理全过程耗时32.43 h,升温速率34.17—74.34℃/h,降温速率15.60—31.57℃/h,升温阶段末壁面平均温度606.62℃,最大壁面温差106.07℃;保温阶段末壁面温差15℃;降温阶段最大壁面温差111.01℃。壁面温度完全满足热处理规程要求,证明以升温均匀度为优化目标,可有效对主吸收塔热处理过程进行工艺设计和优化。

In order to clarify the effect of heat treatment of the main absorption tower and temperature distribution and heat transfer characteristics of the tower wall,a thermal-flow coupling model was established with the main absorption tower as the object,and the whole process of heating-insulation-cooling in heat treatment was simulated.The concept of heating uniformity was proposed,and the influence of inlet flue gas parameters on heating uniformity during heat treatment was analyzed by combining multi-objective genetic optimization algorithm,and optimal heat treatment process technology was obtained.The results show that during heat treatment,high temperature zone and low temperature zone of the wall are located at head and manhole,and heating rate and wall temperature difference are positively correlated with the flame height and the angle of the outer flame surface.Heating rate is positively correlated with the flue gas flow rate.Temperature difference decreases first and then increases.The whole process of heat treatment takes 32.43 h,heating rate is 34.17-74.34℃/h,cooling rate is 15.60-31.57℃/h,average wall temperature at the end of heating stage is 606.62℃,maximum wall temperature difference is 106.07℃,wall temperature difference at the end of the insulation stage is 15 C,and maximum wall temperature difference in the cooling stage is 111.01 C.The wall temperature fully meets the requirements of heat treatment regulations,which proves that the optimization goal of temperature uniformity can effectively design and optimize the heat treatment process of the main absorption tower.