疏浚底泥微波干燥特性及耗能分析.docVIP

疏浚底泥微波干燥特性及耗能分析 　　摘要：为了探索疏浚底泥有效干燥处理的新途径，对疏浚底泥进行微波干燥试验，探讨了不同底泥厚度和微波功率对疏浚底泥微波干燥特性的影响，分析了微波干燥过程中单位能量消耗，并引入薄层干燥模型对底泥干燥过程进行模拟。结果表明，随着底泥厚度的依次增加，干基含水率下降速率逐渐降低，干燥所需时间逐渐延长；微波功率越大，干燥时间明显缩短；10 mm厚底泥最大干燥速率约是40 mm的3.0倍。单位耗能分析表明，不同厚度底泥在280 W下单位耗能较低，能量利用更加充分。通过分析试验数据，确定了疏浚底泥微波干燥过程中水分比变化适用Modified I模型，且模型拟合较好，可用于预测不同厚度疏浚底泥微波干燥至不同含水率所需干燥时间。 　　关键词：关键词：微波干燥；疏浚底泥；干燥特性；耗能分析；干燥模型 　　中图分类号：X705 文献标志码：A 文章编号：1672-1683（2015）06-1128-05 　　Abstract：In this paper，microwave drying of dredged sediment was carried out using domestic microwave oven in order to explore a new way of effective dry processing for dredge sediment.Effects of different sediment thicknesses and microwave power outputs on the drying characteristics of dredged sediment by microwave energy were discussed and the unit energy consumption was analyzed，and thin layer drying model was introduced to simulate the drying process.The results showed that the decreasing rate of dry basis moisture content reduced and the drying time extended with the increasing of sediment thickness successively the drying time shortened significantly with the increasing of the powers；and the maximum drying rate of 10 mm thick sediment was about 3.0 times of that of 40 mm thick sediment.The unit energy consumption analysis showed that the unit energy consumption was lower under 280 W for different thicknesses of sediment，and energy utilization was more effective.Modified I model was determined to be applicable to analyze the microwave drying of sediment through the analysis of experimental data，and the model had good fittings.Therefore，the model can be used to predict the drying time for different thicknesses of dredged sediment with different moisture contents. 　　Key words：microwave drying；dredged sediment；drying characteristics；energy consumption analysis；drying model 　　疏浚底泥是清除湖泊、河流、航道等内源污染而产生的一种固体沉淀物。由于底泥含水率高，且含有少量微生物等特点，对底泥的堆放、运输和处置带来极大的困难。为了有效地处理疏浚底泥，必须对底泥进行深度脱水处理，实现减量化。常用的底泥深度脱水方法主要有机械脱水、药剂脱水以及热干燥[1-3]。然而机械脱水很难将底泥的含水率脱除至50%以下[4-5]，药剂脱水需要根据