半焦孔隙结构的影响因素  

Influential Factors on Pore Structure of Coal-char

作　　者：周毅[1] 段钰锋[1] 陈晓平[1] 赵长遂[1] 吴新[1] 

机构地区：[1]东南大学动力系洁净煤发电与燃烧技术教育部重点实验室,江苏南京210096

出　　处：《锅炉技术》2005年第4期34-38,共5页Boiler Technology

基　　金：国家重点基础研究发展规划(973)基金资助项目子课题(G199902210532)

摘　　要：用氮气等温吸附(77K)方法测量了原煤及其加压、常压部分气化后半焦的BET比表面积,并通过BJH法计算了孔比表面积、孔容积、孔径和孔分布。根据测试结果,从气化操作条件、半焦颗粒粒径、半焦工业分析3方面分析了影响半焦孔隙结构的因素。常压喷动流化床气化中,挥发分析出或热解对半焦孔隙的生成和发展起到主导作用;而加压气化过程中,炭发生的气化反应对半焦孔隙的生成和发展有更加重要的影响。实验中发现在一定的气化工况下,煤焦存在一个合适的颗粒尺寸范围,能形成比较大的孔比表面积和孔容积,有利于增强煤焦的气化反应。The coal-char samples from atmosphere and pressurized partial gasification were measured by nitrogen adsorption at 77 K. Their specific surface areas were determined based on BET model. The average pore size, total pore volumes, pore specific surface areas and pore size distributions were statistically obtained by using BJH theory. The influential factors on pore structure of coal-char were analyzed of operating condition, coal-char size and coal-char proximate analysis. Pyrolysis and devolatilization processes play a leading role to the pore structure of coal-char at an atmosphere spouted fluidized bed gasification. While it is the reaction of coal-char with CO_2 or H_2O that plays a dominant positive impact on promoting formation and development of the coal-char pore structure at the elevated pressure gasification. There may be existed an optimal coal-char size range that makes abundant porosity and bigger pore specific areas to enhance the gasification reaction.

关 键 词：部分气化 半焦 孔隙结构 喷动流化床 

分 类 号：TQ534[化学工程—煤化学工程]