稻秸煤混粒在常规喷动床中的喷动性能

摘要

To obtain spouting characteristics of mixture of straw and coal particle in conventional spouted bed (CSB) in cold state, pressure drop of the bed and circulating rate of the mixture were used to show spouting behavior.The pressure drop of the bed with superficial air velocity, the effects of various parameters, such as proportion of mixture, height of the mixture and jet diameter on the pressure drop and the circulating rate of the mixture with air flow rate were all studied.Uniform design experiments were done to get regression equations to explain spouting characteristics.The results show that the pressure drop of the bed with superficial air velocity corresponds to that of CSB, and the curves of pressure drop and circulating rate ,which were obtained in conditions of 0 ～ 30％ straw in the mixture, 250 ～ 340 mm height of the mixture and 25 ～ 41 mm jet diameter, may be used to guide selecting spouting parameters.Three regression equations were obtained by SPSS.The dependent variables in these equations are circulating rate of the mixture, pressure drop of unit material height, and circulating rate of the mixture per effective power, respectively, and the independent variables are jet diameter, air flow rate and height of the mixture.%为了得到稻秸粒和煤粒混料在常规喷动床中冷态共喷时的喷动性能,采用床层压降和物料循环速率表征喷动行为,研究了床层压降随表观风速的关系曲线,以及稻秸煤粒混合比例、混料高度和喷口直径3个因素对床层压降表观风速关系曲线和对物料循环速率风量关系曲线的影响,实施了3因素12拟水平的均匀设计试验以求取表示喷动性能的回归方程.结果表明:床层压降表观风速关系符合常规喷动床特征,稻秸占混料质量分数为0～30%,混料高度为250～340 mm,喷口直径为25～41 mm时,压降曲线和物料循环速率曲线可用于指导选择喷动条件.采用SPSS软件回归分析得到了3个可用于预测喷动性能的回归方程,因变量分别是物料循环速率、单位料高下床层压降及单位有效功率的物料循环速率,自变量为喷口直径、风量和混料高度.