造纸污泥薄层干燥实验及动力学模型分析

通过造纸污泥薄层干燥实验，考察了温度对造纸污泥干燥特性的影响，引入薄层干燥模型对污泥干燥动力过程进行模拟。结果表明，泥层越薄和干燥温度越高，污泥干燥的速率就越快，当干燥温度从80℃上升到160℃时，相对应的最大干燥速率从0.008g/(g·min)上升到0.030g/(g·min)；Modified page模型描述了薄层造纸污泥在烘箱中的干燥过程，应用Fick扩散模型，薄层造纸污泥在干燥温度为80℃～160℃时，有效扩散系数为2.2×10^-10m²/s~3.96×10^-10m²/s。通过Arrhenius方程建立温度和有效扩散系数之间的关系，得出水分扩散的活化能为9.435kJ/mol。

Experiment and kinetics model analysis on thin layer drying of paper mill sludge

A series of experiments on the thin-layer drying of paper mill sludge were carried out to investigate the effects of temperature on the drying characteristics of paper mill sludge, and the thin-layer drying model was adopted to simulate the process of sludge drying. The result shows that the higher the temperature of drying and the thinner the layer of drying, the quicker the rate of drying. As the drying temperature rises from 80℃ to 160℃, the maximum drying rate increases from 0.008g/(g·min) to 0.030g/(g·min). Modified page is a model to best describe the drying process of the paper mill sludge in oven. In addition, moisture transfer from paper mill sludge can be described by Fick′s diffusion equation. It is obtained that the effective diffusion coefficient of dried samples of paper mill sludge ranges from 2.2×10^-10m²/s to 3.96×10^-10m²/s at temperatures from 80℃ to 160℃. By using Arrhenius equation, the activation energy of 9.435kJ/mol for the moisture diffusion is determined.