液态二氧化碳防火机理及远距离输送技术

Mechanism of liquid CO_(2)fire prevention and long-distance transportation technology

浅埋极近距离煤层群自然发火是榆树坡煤矿大部分煤层的典型特征,煤田火区治理困难。通过热分析试验,探究液态CO_(2)的使用对高温煤体降温规律及自燃特性的影响,观察到松散煤体的孔隙率对CO_(2)的降温效果有显著影响;CO_(2)体积分数的增加能够影响煤氧化的表观活化能,为解释CO_(2)抑制煤自燃的作用提供了理论依据。利用Fluent数值模拟软件,计算液态CO_(2)注入采空区的扩散半径,得出液态CO_(2)对采空区遗煤的有效惰化半径。

The natural ignition of shallow burial,very close coal seam groups is typical characteristics of most of the coal seams in Yushupo coal mine in China.It is difficult to manage the fire zone in the coal field and the safety is threatened.Through thermal analysis experiments,the influence of the use of liquid CO_(2)on the cooling law and spontaneous combustion characteristics of high temperature coal body is studied,and it is observed that the porosity of loose coal body has a significant effect on the cooling effect of CO_(2);it is emphasized that the increase of CO_(2)concentration can affect the apparent activation energy of coal oxidation,which provides a theoretical basis for explaining the role of CO_(2)in inhibiting coal spontaneous combustion.Fluent numerical simulation is adopted to calculate the diffusion radius of liquid CO_(2)injected into the mining area,and to obtain the effective inerting radius of liquid CO_(2)on the coal left in the mining area.