盖层对煤堆积床阴燃过程影响的小尺度实验研究  

Small-Scale Experimental Study on Effects of Covering Layer on Smoldering in Packed Coal Beds

作　　者：刘志航 李君[1] 潘俊杰 Liu Zhihang;Li Jun;Pan Junjie(School of Mechanical Engineering,Tianjin University,Tianjin 300350,China)

机构地区：[1]天津大学机械工程学院,天津300350

出　　处：《燃烧科学与技术》2024年第6期600-608,共9页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(52276130).

摘　　要：为掌握盖层影响下煤火阴燃传播情况,根据地下煤火的空间结构特征,设计搭建了实验室小尺度煤堆积床阴燃实验装置,在煤层上方放置多孔陶瓷模拟真实煤火中的上覆盖层.通过改变盖层中的裂隙特征揭示了盖层对煤阴燃传播过程及烟气排放的影响.结果表明,煤层上方存在完整的气体通路,是在盖层影响下阴燃成功点火和传播的必要条件.改变盖层中裂隙之间的距离会影响裂隙向下方煤体供氧的能力,从而影响煤阴燃到达峰值温度的时间.盖层主要对浅层煤层阴燃产生影响.随着盖层裂隙开度的减小,煤层阴燃反应速率逐渐下降,峰值温度逐渐降低;在本实验条件下,裂隙开度为4 mm时,阴燃无法传播.To grasp the smoldering propagation of coal fires under the effect of covering layer,based on the spatial structure characteristics of underground coal fires,a small-scale laboratory coal-packed bed smoldering experimental device was designed and built,and porous ceramics were placed above the coal seam to simulate the covering layer in the real coal fire.The effects of covering layer on coal smoldering propagation and flue gas emission are revealed by changing the crack characteristics in the covering layer.The results indicate that a complete gas path above the coal seam is necessary for the successful ignition and propagation of smoldering under the influence of the covering layer.Changing the distance between the cracks in the covering layer will affect the ability of the cracks to supply oxygen to the lower coal layer,thus affecting the time needed to reach the peak temperature of coal smoldering.The covering layer mainly affects the smoldering of the shallow coal layer.With the decrease of crack opening,the reaction rate and peak temperature of coal smoldering decrease gradually.Under the experimental conditions,when the crack opening is 4 mm,smoldering fails to propagate.

关 键 词：地下煤火 煤堆积床 阴燃 盖层 温度场 烟气排放 

分 类 号：TK11[动力工程及工程热物理—热能工程]