昭通褐煤气力输送临界水分含量研究  

Critical Moisture Content of Pneumatic Conveying of Zhaotong Lignite

作　　者：贺春辉[1] 沈湘林[1] 周海军[1] 

机构地区：[1]能源热转换及其过程测控教育部重点实验室(东南大学),江苏省南京市210096

出　　处：《中国电机工程学报》2014年第11期1725-1734,共10页Proceedings of the CSEE

基　　金：国家重点基础研究发展规划项目(973计划)(2010CB227002);国家863高技术基金项目(2011AA05A201)~~

摘　　要：研究昭通褐煤水分含量对其气力输送的影响，获得了其输送临界水分含量，并从煤粉流动性出发，对临界水分进行了初步解释，得到了初步判别标准。进一步从褐煤水分赋存形态出发，对临界水分问题进行了探讨。结果表明：昭通褐煤全水分约29％时，输送表观气速出现大幅度增大，全水分约30％时无法正常输送，判断其输送临界水分为29％～30％。煤粉流动性测量可为临界水分判别提供初步参考标准。在临界水分附近，煤粉流动性发生区域转变，流动性变差。粒间水是影响煤粉流动和输送的主要水分因素，粒内水对输送的影响很小。虽然褐煤全水分较高，但大量水分以粒内水形式存在，粒间水含量较少。昭通褐煤输送临界水分附近，粒间水含率约为6％，粒间水占粒间空隙体积的比率约为7％。The influence of moisture content on pneumatic conveying of Zhaotong lignite was investigated, and the critical moisture content of pneumatic conveying of Zhaotong lignite was obtained. The flowability and water morphology of lignite coal powder was researched, and the preliminary criterion of critical moisture content was explored. The results indicate that superficial gas velocity substantially increases while Zhaotong lignite is conveyed with a total moisture content reaching about 29 %, and it could not be conveyed when this value reaches about 30%. The critical moisture content of pneumatic conveying of Zhaotong lignite is about 29%-30%. Flowability measurement could provide a preliminary judgement on the critical moisture content. Near the critical moisture, the flowability became worse. Intergranular water was the main factor that affect flowability and pneumatic conveying, intraparticle water had little effect on them. For Zhaotong lignite, the intergranular water content is about 6 %, and the volume ratio of intergranular water to intergranular voidage was about 7%.

关 键 词：气力输送 临界水分含量 昭通褐煤 水分赋存形态 

分 类 号：TQ51[化学工程]