摘要
针对近年来兴起的污泥低温热干化技术,采用热重实验分析方法,研究了城市污水处理厂污泥低温对流干燥动力学特性.实验发现:在低温干燥条件下(40~80,℃),污泥降速干燥过程可分为一次降速干燥和二次降速干燥两个阶段;随热风温度降低,低干燥速率的二次降速阶段所占时间比例大幅增加,是污泥低温干燥耗时较长的原因.利用反应工程方法理论,解释了污泥低温干燥过程中产生一次和二次降速干燥阶段的原因,同时,拟合了各干燥阶段脱水机理函数.
The thermogravimetry(TG)and differential thermogravimetry(DTG)method was applied to study the low- temperature convective drying characteristics of municipal sewage sludge. It was found that when the drying gas was at a low temperature of 40-80℃, the sludge drying rate decreased. The decreased process can be divided into two stages. The second rate falling stage had a lower drying rate due to the decrease of the drying gas temperature and caused more time. The reac- tion engineering approach (REA) has been employed to explain the mechanism of the two drying rate falling stages. Water evaporation mechanism functions in the two stages were also presented.
出处
《天津科技大学学报》
CAS
2012年第4期52-56,共5页
Journal of Tianjin University of Science & Technology
基金
国家自然科学基金资助项目(21106104)