污泥薄层干燥特性及动力学模型分析

Characteristics of Thin-Layer Drying and Analysis of Kinetic Model for Sewage Sludge

对桐乡污水处理厂的污泥薄层干燥特性进行了研究,得到其在不同温度、厚度条件下半干化处理的干燥速率和失水曲线。结果表明,污泥的失水速率随着厚度减小、温度上升而增大。引入了干燥动力学模型,Midilli模型能够很好地模拟污泥的失水情况。污泥中湿分的有效扩散系数在3.383×10^(-10)~5.130×10^(-9)m^2/s,2.5 mm厚度的干燥活化能为1.664 kJ/mol,为实际的污泥处理系统的设计提供了依据。

Drying characteristics of sludge from Tongxiang Wastewater Treatment Plant were discussed. Drying rate and water loss curve under different temperature and thickness conditions were obtained. The results showed that water loss rate of sludge increased with the decrease of thickness, and the increase of temperature. Drying kinetic model was also introduced, and Midilli model could properly simulate water loss of the sludge. Effective diffusion coefficient of moisture sludge was 3.383×10^（-10）5.130×10^（-9）m2/s,and activation energy was 1.664 kJ/mol for 2.5 mm thickness. The results provided a basis for the design of actual sludge treatment system.