防控高温煤岩裂隙的膏体泡沫研制及应用

煤岩裂隙漏风导致的煤自燃火灾严重危害矿井安全生产，在现有防治煤炭自燃材料的基础上，以聚丙烯酰胺（A）、复合表面活性剂（B）、混合粉体（C）为原材料研制了一种防控高温煤岩裂隙的膏体泡沫。采用正交试验法以保水率、发泡倍数、阻化率为指标优选出了最佳的膏体泡沫配方为A4B4C4:A为70 g/L，B为19.5 g/L，C为270 g/L。对膏体泡沫进行了微观形态表征，并从泡孔尺寸大小及分布、液膜颗粒分布、液膜载体吸水等方面对膏体泡沫的保水、吸热和受热稳定机制进行了分析。最后以南方某煤矿复采工作面煤自燃发火为例，分析和判定了302工作面火区分布，采用钻孔压注膏体对火区高温煤岩裂隙进行控制，3d后工作面1-5#钻孔、三石门密闭处CO浓度从520 ppm,465 ppm,523 ppm,305 ppm,289 ppm,750 ppm下降到22 ppm,18 ppm,23 ppm,14 ppm,14 ppm,36 ppm。

Development and application of paste foam for prevention and control of fracture in high temperature coal and rock

The spontaneous combustion fire of coal caused by the air leakage of fracture in coal and rock will harm the work safety of coal mine seriously. On the basis of the existing materials for prevention and control of coal spontaneous combustion, a kind of paste foam for prevention and control of fracture in high temperature coal and rock was developed by taking polyacrylamide (A), composite surfactant (B), and mixed powder (C) as the raw materials. The optimum formula of the paste foam was determined to be A4B4C4 by using the orthogonal test method and taking the water retention rate, the foaming ratio and the inhibition rate as the optimization indexes, in which A was 70 g/L, B was 19.5 g/L, and C was 270 g/L. The micro morphology of the paste foam was investigated, then the mechanism of water retention, heat absorption and heat stability of the paste foam were analyzed from the aspects of the size and distribution of the bubble size, the distribution of the liquid membrane particles, and the water absorption of the liquid membrane carrier. Finally, taking the spontaneous combustion of coal in repeated mining face of a certain coal mine in south China as an example, the distribution of fire zone in 302 working face was analyzed and judged, then the paste foam was injected through the boreholes to control the fracture of high temperature coal and rock in fire zone. After three days, the concentrations of CO at the 1-5# boreholes in the working face and the NO.3 cross-hole sealing decreased from 520 ppm, 465 ppm, 523 ppm, 305 ppm, 289 ppm and 750 ppm to 22 ppm, 18 ppm, 23 ppm, 14 ppm, 14 ppm and 36ppm respectively.