生活垃圾水泥窑协同处置的干燥动力学研究

摘要

为了充分利用水泥生产中的尾气余热,本研究对生活垃圾的分选筛下物进行了干燥动力学实验,并估算了恒速段的体积平均传热、传质系数,最后对尾气除臭工艺中的冷凝水质进行了抽样分析.结果表明:热风温度和热风流速增加都能提升筛下物的干燥速率,而料层厚度增加则减缓干燥速率.料层厚度是影响平均传热和传质系数最重要的因素,随着料层厚度降低而显著增加;热风流速增加能提升系统平均传热和传质系数;而热风温度的影响相对较弱.尾气冷凝水中COD、SS和BOD5含量较低,满足GB 8978-1996污水综合排放标准中的三级标准,而NH4-N排放超出限值.%In order to make full use of waste heat in cement production,the drying kinetics experimental research of the domestic waste under the sieve was carried out.We estimated the average heat and mass transfer coefficients on the constant velocity section,and done a lots of sampling analysis of the tail gas condensate water quahty.The results showed that the drying rate of the siftage increased as the temperature or the velocity of the hot air increased,and decreased with the bed depth increased.The average heat and mass transfer coefficient increased obviously with the bed depth or hot air velocity.And the bed depth is the most important influential factor,while the influence of the hot air temperature is relatively weak.The COD,SS and BOD5 of the tail gas condensate water could satisfy the third standard of the Integrated Wastewater Discharge Standard (GB 8978-1996),but the NH4-N discharge exceeded the limit.