含水煤堆自燃升温特征的实验研究

Experimental Study of Spontaneous Combustion Heating up Features of Coal Pile Containing Water

为了了解露天含水煤堆自燃过程中温度变化特性,利用模拟和实验手段研究了煤堆内部温度的动静态分布情况,结果表明:含水煤堆升温过程经历了升温—缓慢升温—快速升温三个阶段,水分的存在使煤堆在自燃中期升温速率放缓,水分含量越高,水分蒸发所需时间越长,煤堆安全保存期越长,水分蒸发完毕后煤堆进入快速升温阶段,温度模拟结果与煤堆升温实验数据在趋势上比较符合,降雨和注水作业都会对煤堆升温过程产生较大的影响,对高温煤堆进行大量注水,只会起到临时的灭火效果,本质上是促进自燃明火发生,适当的循环注水可以起到较长的冷却效果。

In order to understand the temperature dynamic feature of open coal pile containing water,the simulation and experimental method are used to study the dynamic and static temperature distribution.The results show that coal pile containing water goes through three stages,including heating,slow heating and fast heating,the water existence can slow down the coal pile heating up in middle-term of spontaneous combustion and the more moisture,the longer time for water evaporation and the longer safe storage time and also when the water fully evaporates,the coal pile goes into rapid heating up process.The temperature simulation results conform to the coal pile heating up experimental data,the rain and water injection both obviously affect heating up process,the larger water injection for high temperature coal pile can essentially promote the spontaneous combustion although it has temporary fire control effect,and the appropriate circular water injection has a longer cooling effect.