论文部分内容阅读
本文对褐煤薄层微波干燥动力学特性进行实验研究,分析微波功率及添加剂(剂量分别为5％和10％氯化钠、剂量5％碳酸钠)对褐煤干燥动力学特性的影响规律.结果表明:添加剂对褐煤微波干燥特性具有显著性影响.与原褐煤相比,功率为119 W时添加剂效果最为显著,添加5％氯化钠、5％碳酸钠和10％氯化钠后,褐煤平均干燥速率分别增大3％、20％和36％.纯褐煤、褐煤/5％氯化钠、褐煤/5％碳酸钠和褐煤/10％氯化钠第一降速段活化能分别为17.17W.g-1、14.60 W·g-1、13.48 W·g-1和13.33 W·g-1;第二降速段活化能分别为15.23 W·g-1、10.51 W·g-1、10.12W.g-1和9.32 W·g-1.添加剂加入均使得褐煤两个降速段活化能降低,与5％剂量氯化钠相比,添加10％氯化钠后褐煤的活化能有所降低;碳酸钠可更好的改善褐煤薄层微波干燥特性.“,”Effects of microwave power levels and additives (5％ and 10％ sodium chloride,5％ sodium carbonate) on the microwave drying kinetics of lignite thin layer were evaluated in a microwave drier.The additives had significant effects on the microwave drying performance of the lignite thin layer.Especially,in comparison with raw lignite,the average drying rates at 119 W for lignite blending with 5％ sodium chloride,5％ sodium carbonate and 10％ sodium chloride increased by 3％,20％ and 36％.The apparent activation energies of raw lignite,lignite/5％ sodium chloride,lignite/5％ sodium carbonate and lignite/10％ sodium chloride in the first falling rate period were 17.17 W·g-1,14.60 W.g-1,13.48 W.g-1 and 13.33 W.g-1;while in the second falling rate period,which were 15.23 W.g-1,10.51 W.g-1,10.12 W.g-1 and 9.32 W·g-1.The apparent activation energies of both falling rate periods for lignite blending with additives were less than that of the raw lignite,indicating that additives were available for improving thin layer drying performance of the lignite.The apparent activation energies of lignite/10％ sodiun chloride were less than that of lignite/5％ sodium chloride.Sodium carbonate could be the preferable one in comparison with sodium chloride at the same blending ratio.