褐煤热解碎裂特性及孔隙结构演化研究  

Research on the pyrolysis fragmentation characteristics and pore structure evolution of lignite

作　　者：常赵刚 CHANG Zhaogang(CCTEG China Coal Research Institute,Chaoyang,Beijing 100013,China;National Energy Key Laboratory of Coal Efficient Utilization and Emission Control Technology and Equipment,Chaoyang,Beijing 100013,China;Beijing Key Laboratory of Coal Based Carbon Materials,Chaoyang,Beijing 100013,China)

机构地区：[1]煤炭科学技术研究院有限公司,北京市朝阳区100013 [2]国家能源煤炭高效利用与节能减排技术装备重点实验室,北京市朝阳区100013 [3]煤基节能环保炭材料北京市重点实验室,北京市朝阳区100013

出　　处：《中国煤炭》2024年第7期141-147,共7页China Coal

基　　金：煤科院新产品新工艺开发项目(2022CG-MH-01)。

摘　　要：褐煤在热解过程中受热力作用极易发生碎裂粉化,制约着褐煤清洁高效转化利用,而研究褐煤热解碎裂特性可为其加工利用技术发展提供参考,因此利用微型热解装置选取内蒙古褐煤,研究其挥发分析出过程与碎裂变化的关系,并分析半焦的孔隙结构演化特征与碎裂特性的联系。研究结果表明,褐煤热解的碎裂程度随加热温度的升高而增大,在流化床中碎裂现象更显著;挥发分析出是引发褐煤热解碎裂的主要因素,褐煤在不同反应温度下的挥发分析出率和粒度变化率、粉化率的关系均存在变化的转折点,可为工业生产提供参考数据;随加热温度升高孔隙结构不断生成和发育,孔隙特征均为尖劈形的毛细孔,在650℃时孔隙结构最丰富,在热力作用下达到煤颗粒材质临界值而发生破碎粉化。Lignite is prone to fragmentation and pulverization during pyrolysis due to thermal effects,which restricts the clean and efficient transformation and utilization of lignite,so research on lignite pyrolysis fragmentation characteristics can provide reference for the development of lignite processing and utilization technology.Taking Inner Mongolia lignite and micro-pyrolysis device to study the correlation between the process of volatile matter separation and the change of fragmentation,the relationship between the evolution characteristics of pore structure and fragmentation characteristics of semi-coke was analyzed.The experimental results showed that the fragmentation degree of lignite pyrolysis increased with the increase of the heating temperature,and the fragmentation phenomenon was more significant in the fluidized bed.Volatile matter separation was the main factor leading to the pyrolysis fragmentation of lignite,and the relationship between volatile matter separation rate and particle size change rate or pulverization rate of lignite at different reaction temperatures had a turning point,which could provide reference data for industrial production.As the heating temperature rose,pore structures were constantly formed and developed,and the pore characteristics were cleft-shaped capillary pores,and the pore structure was most abundant at 650℃,and the coal particle reached the critical value of materials to be crushed and pulverized under the action of heating action.

关 键 词：褐煤热解 碎裂特性 挥发分析出率 半焦孔隙结构 

分 类 号：TQ530.2[化学工程—煤化学工程]