【摘要】 为了研究污泥在常温下的干燥特性,采用自制的污泥干燥装置对城市脱水污泥进行常温干燥实验。研究了不同厚度（10、20、30 mm）和不同风速(0、1、3 m·s^-1)条件下污泥含水率随时间变化的规律,并用常见的干燥模型对污泥常温干燥过程进行拟合。结果表明:常温条件下,10 mm厚度污泥的干燥速率均高于20 mm和30 mm厚度污泥的干燥速率,并且在风速较低时,降低污泥厚度对缩短干燥时间的效果更加显著;污泥厚度不同,风速对污泥干燥的影响作用不同,对于10 mm厚度的污泥,增加风速可显著缩短干燥时间,而对于20 mm和30 mm厚度的污泥,风速需增加到一定数值(如3 m·s^-1)时,才能显著缩短干燥时间;Logarithmic模型更适合描述污泥在常温条件下的干燥,干燥过程中的有效扩散系数为1.73×10^-91.38×10^-8m²·s^-1。更多还原

【Abstract】 In order to study room temperature drying characteristics of sludge,drying experiments of sewage sludge were carried out in homemade equipment.The sludge moisture rate versus time was studied at different sludge thicknesses（10,20,30 mm） and air velocities(0,1,3 m·s^-1).Common drying models were applied to simulate the drying curves.The results showed that the drying rate at the thickness of 10 mm was higher than that at the thickness of 20 mm and 30 mm.The thickness of sludge had more influence on sludge drying when the air velocity was low.The effect of air velocity on sludge drying differed at different sludge thicknesses.At the thickness of 10 mm,sludge drying time fell a lot with the increase of air velocity.But the drying time would not shortened sharply at the others unless the air velocity up to a certain value(such as 3 m·s^-1).Logarithmic Model was more suitable for describing the sludge drying process at room temperature,and the effective diffusion coefficient was equal to 1.73 × 10^-9 1.38 × 10^-8m²·s^-1.更多还原