一、引言我国约有50%的矿井开采的煤层存在着自燃发火危险,井下煤的自燃必须具备下面几个条件,即煤本身具有内在的自燃性能;连续供给一定浓度的氧气;以及有良好的蓄热环境。只有三个条件同时存在才会引起自燃,只要能够破坏一个或一个以上的条件就可防止自燃。对于一个特定的易自燃煤层,浮煤厚度及其顶底板的导热性能一定时,影响自燃的主要因素就是破碎煤体中空气的流动性能.这时漏风风流的速度及数量对自燃发火起着主导的作用。井下漏风使粉煤氧化放热,并将一部分热量带走。因此, I. INTRODUCTION There is a danger of spontaneous combustion in the coal seam mined in about 50% of the mine in our country. The spontaneous combustion of underground coal must meet the following conditions: the coal itself has inherent self-ignition capability; continuous supply of certain concentration of oxygen; and good Thermal storage environment. Only three conditions exist at the same time will cause spontaneous combustion, as long as the destruction of one or more conditions can prevent spontaneous combustion. For a particular spontaneous combustion coal seam, the thickness of the floating coal and the thermal conductivity of the roof and floor are constant, the main factor that affects the spontaneous combustion is the flowability of the air in the crushed coal, in which case the speed and quantity of air leakage are the main factors that cause spontaneous combustion Role. Downhole air leakage to the pulverized coal oxidation heat, and some of the heat away. therefore,