基于大型煤堆实验台的煤自燃过程模拟研究

Study on Simulation of Coal Spontaneous Combustion Process Based on Large Coal Pile Experiment Rig

为研究王台铺矿15号煤层的自然发火规律,利用大型煤堆实验台对其进行了试验模拟研究,通过热电偶测得煤体的温度变化情况,得到煤体内的升温速率、耗氧速度、临界温度及干裂温度等煤样自燃特性参数,结合气相色谱仪对煤自燃过程中产生的指标气体进行分析。结果表明:煤温在临界温度80℃以下时,煤的自身氧化反应过程中产生的热量小,煤样耗氧速度较低,煤体很难发生自燃;在80～110℃时,耗氧速度逐渐增加,反应逐渐加强;当煤温超过干裂温度110℃后,氧化反应急剧加快,放热量也随着增大,同时CO和CO2产生率加快,煤体易发生自燃。

In order to study the spontaneous combustion law of No.15 seam in Wangtaipu Mine,a large coal storage pile experiment rig was applied to the experiment simulation study.With the temperature variation conditions of coal measured with the thermal electric couples,the coal sample spontaneous combustion feature parameters were obtained including the temperature rising rate in the coal,the oxygen consumption speed,the critical temperature and dry fracturing temperature.In combination with the gas phase chromatographer,the index gas occurred from the coal spontaneous combustion process was analyzed.The results showed that when the coal temperature was below 80 ℃ of the critical temperature,the thermal value occurred from the oxidized reaction process of coal would low,the oxygen consumption speed of coal sample would low and the spontaneous combustion of the coal would be difficult to be occurred.When the critical temperature was 80~110 ℃,the oxygen consumption speed would be steadily increased and the reaction would be steadily enhanced.When the coal temperature was over 110 ℃ of the dry fracturing temperature,the oxidized reaction would rapidly increased and the thermal emission value would be increased.Meanwhile,the CO and CO2 production rate would be increased and the spontaneous combustion of the coal would be easily occurred.