气氛热预处理对胜利褐煤组成、结构及快速热解特性影响OA

The pyrolysis of coal is an inevitable path for the clean and efficient conversion and utilization of coal.Exploring the influence of the physical and chemical structures of coal on its pyrolysis behavior is of great significance.The Shengli lignite(SL)was subjected to thermal pretreatment in CH4 and H2 atmospheres respectively,and the structures before and after the atmospheric thermal treatment were systematically characterized,and fast pyrolysis experiments were conducted in a fluidized bed reactor.The influence of structural changes of SL on its pyrolysis behavior was explored.The results show that the atmospheric thermal pretreatment removes some oxygen-containing functional groups of SL,reduces the ratio of the number of O/C atoms,breaks the cross-linked structure,lowers the activation energy required in the active stage of pyrolysis(400～480℃),and is conducive to the generation of pyrolysis tar.Meanwhile,some weak chemical bonds break during the atmospheric thermal pretreatment process,resulting in a decrease in the yield of pyrolysis gas,an increase in the yield of semi-coke,and a decrease in the content of light tar.CH4 atmosphere can inhibit the breakage of aliphatic side chains during the atmospheric thermal pretreatment process,and H2 atmosphere is more conducive to the decomposition of oxygen-containing groups in SL and depolymerization of the macromolecular structure of coal to increase the yield of pyrolysis tar.