防治煤自燃与瓦斯复合灾害的膏体速凝固结材料研制

Development of paste rapid setting and solidifying material for preventing and controlling compound disaster of coal spontaneous combustion and gas

为了防治矿井内破碎煤岩体以及采空区等跨尺度裂隙场中的煤自燃与瓦斯复合灾害,从理论上分析煤自燃与瓦斯复合灾害“诱-抑”机理,采用均匀设计试验的方法,以失去流动性的时间(LFT测试装置)T、静置20 min后浆体的泌水量V及最大温差W为试验指标,进行数据分析和规划求解改善膏体速凝固结材料的性能,进行材料封堵性能的试验,并剖析材料的反应机理,研制出1种能在放热少的同时对煤岩裂隙进行快速封堵,从而防治煤自燃与瓦斯复合灾害且绿色经济环保易制备的新型材料。研究结果表明:方案P或水灰比K对T,V及W都有显著影响;材料效果最佳的掺量为硫铝酸盐水泥44.6 wt%、石膏44.6 wt%、硫铝酸钙1.6 wt%、粉煤灰0 wt%、硫酸铝9.2 wt%以及材料水灰比4.75∶1;材料灌注前后最大负压差为15.8 kPa,证明材料对煤岩裂隙具有很好的封堵性能。研究结果可为煤自燃与瓦斯复合灾害防治提供参考依据。

In order to prevent and control the compound disaster of coal spontaneous combustion and gas in the cross-scale fracture field such as broken coal and rock mass in the mine and goaf,the“inducement-suppression”mechanism of the compound disaster of coal spontaneous combustion and gas was theoretically analyzed.The uniform design test method was used,with the time of loss of fluidity(LFT test device)T,the water leakage volume of slurry after standing for 20 minutes V,and the maximum temperature difference W as the test indicators,the data analysis and programming solving were carried out to improve the performance of p rapid setting and solidifying material.The experiment of material plugging performance was conducted,then the reaction mechanism of the material was analyzed,and a new material that can quickly plug coal and rock fractures while releasing the least heat was developed to prevent and control the compound disaster of coal spontaneous combustion and gas,and it was green,economical,environmentally friendly and easy to prepare.The results show that the scheme P or water-cement ratio K has significant influence on T,V,and W.The optimal mixing ratio of the material is 44.6 wt%of sulphoaluminate cement,44.6 wt%of gypsum,1.6 wt%of calcium sulphoaluminate,0 wt%of fly ash,9.2 wt%of aluminum sulfate,and a water-cement ratio of 4.75∶1.The maximum negative pressure difference before and after material injection is 15.8 kPa,which proves that the material had good plugging performance for coal and rock fractures.The results can provide a reference for preventing and controlling the compound disaster of coal spontaneous combustion and gas.