A series of experiments about thin-layer drying of dyeing sludge were carried out to investigate the effects of temperature and thicknesses on drying characteristics of dyeing sludge.The results were com-pared with that of paper mill sludge.By adopting different thin-layer drying models,the Modified Page model was finally chosen as the drying model to simulate the sludge drying process.Moreover,the effective diffusion coefficient and activation energy of the dyeing sludge was calculated.The results show that,the higher the drying temperature and the thinner the drying layer,the higher drying rate the dyeing sludge. Obvious difference existed between drying performance of different sludges.The thickness of dyeing sludge had more dramatic influence on the drying rate than the paper mill sludge.When the drying temperature was between 140 ℃ and 200 ℃,the effective diffusion coefficient of moisture in the dyeing sludge ranged from 2.966 7×10-8 m2/s to 8.388 8×10-8 m2/s,and the activation energy was 3.88 kJ/mol,which was lower than the paper mill sludge (5 .5 5 5 kJ/mol).%通过印染污泥薄层干燥试验,研究干燥温度和污泥厚度对印染污泥干燥特性的影响,并与造纸污泥进行对比,比较不同薄层干燥数值模拟模型,最终选用Modified Page模型描述印染污泥薄层干燥过程,求出印染污泥的有效扩散系数和活化能.结果表明,干燥温度越高、污泥厚度越薄,污泥干燥速率越大；不同污泥干燥特性存在明显差异,印染污泥厚度对干燥速率的影响程度比造纸污泥大；当干燥温度为140~200℃时,印染污泥的有效扩散系数为2．9667×10－8~8．3888×10－8 m2/s；印染污泥水分扩散的活化能为3．88 kJ/mol,比造纸污泥低5．555 kJ/mol.
展开▼
