褐煤干燥提质和无粘结剂成型技术的研究现状及进展

论述了褐煤中水分的存在形式,即褐煤中的水分主要由外在水分、内在水分和结晶水组成,其中外在水分较易脱除。介绍了国内外褐煤干燥提质技术、针对高水分褐煤干燥研发的新技术及与褐煤干燥相关的其他提质技术的研究进展,其中,新研发的褐煤干燥技术中,过热蒸汽流化床褐煤干燥技术(WTA)具有效率高、能耗低、安全等特点,在单位能耗方面具有明显优势。通过对褐煤无粘结剂型煤的成型工艺及型煤耐水性能的试验研究,说明褐煤无粘结剂成型技术制备的型煤样品质量良好,吸收水分的速率大大降低,热解与燃烧活性也有所下降。最后分析了褐煤无粘结剂成型机理,即主要有沥青假说、腐植酸假说、毛细孔假说、胶体假说和分子粘合假说5种。

Research on lignite drying and upgrading technology and its binderless briquetting

Introduce three existence types of water in lignite,which are surface moisture,inherent moisture and crystal moisture,the first is readily removed.Describe lignite drying and upgrading technologies and their development status at home and abroad.Among them,technologies applied to high moisture lignite and other relevant upgrading technologies are emphasized.The striking facts about superheated steam fluidized bed lignite drying technology(WTA) are higher efficient,lower energy consumption and great security,especially unit energy consumption.The briquetting technology used to prepare lignite binderless brequetting and the production’s moisture resistance property are analyzed.The experimental results show that briquette sample has high quality,water absorption rate has been sharply reduced,pyrolysis and combustion activity also have been reduced in some extent.At last,analyze lignite binderless briquetting mechanism,which mainly contains pitch hypothesis,humic acids hypothesis,capillary pores hypothesis,colloid hypothesis and molecule adhesion hypothesis.