煤的理化性质对生物质和煤共热解焦油性质的影响

Effects of coal physicochemical on tar characteristics during co-pyrolysis of biomass and coal

将木屑分别与黑山煤、神木煤以不同比例掺混,利用自制热解干馏炉进行共热解实验。比较木屑的添加对共热解焦油、水和轻质焦油产率的不同影响,结合煤和生物质的热重分析结果与煤的13C核磁共振分析表征,探讨煤的结构、煤和生物质的热化学反应特性,对共热解焦油产率和品质的作用机理。结果表明:在一定配比范围内,木屑和煤之间的交互作用明显提高了共热解焦油中轻质组分的产率,同时热解水产率低于计算值;轻质焦油中的脂肪烃组分主要由木屑和煤热解产生的烷基自由基相互化合生成;煤热解产生的芳烃类自由基由于与生物质热解产生的羟基自由基生成杂酚化合物,从而抑制了热解水的生成。

Saw dust,Heishan coal and Shenmu coal were chosen as raw materials. Co-pyrolysis experiments of biomass and coals were performed with difference blending ratios in a tubular furnace.The effects of saw dust additives were investigated and compared upon the co-pyrolysis yields of tar,water and light tar. Then,the thermogravimetric analyses of raw materials and the structure of coals was tested by13 C NMR. The yield and quality mechanisms of co-pyrolysis tar were further discussed,based on the yield comparison of pyrolytic products,thermal chemical reactivity of raw materials and the structure of coals. The results indicated that significant interactions of saw dust and coals increased the yield of light tar and decreased the water yield in the proper blending ratios during copyrolysis. Moreover,the aliphatic hydrocarbon of light tar was derived from alkyl radicals of the pyrolysis of biomass and coal. And the generation of pyrolytic water was inhibited because aromatic radicals of coal were converted to creosotes by the hydroxyl radicals from biomass pyrolysis.