瓦斯抽采钻孔动态密封黏液型材料实验研究

Experimental study on dynamic sealing of mucilage material in gas extraction borehole

为解决动态密封方法中现有黏液材料无法有效封堵煤岩漏气通道的问题,本文对钠基膨润土进行了改性研究。以钠基膨润土为基料,选取黏合剂羧甲基纤维素钠(CMC)、保水剂聚丙烯酰胺(PAM)和表面活性剂脂肪酸甲酯磺酸钠(MES)作为添加剂,研制出一种能与煤壁紧密结合的动态密封黏液型材料。通过单因素实验分别考察了表面活性剂掺量、保水剂掺量及水料比的变化对材料黏度及流动性的影响,掌握了各因变量随自变量的变化趋势。在此实验基础上,根据正交实验原理设计了三因素三水平17组配比实验,对17组实验所得黏液的黏度进行了统计,根据30 min内所得材料黏度值进行拟合与回归性分析,得到了拟合二次回归方程。其次,通过方差分析、等高线分析及响应曲面分析判断出各因素交互性对实验结果的显著性,分析表明3因素显著性排序为:保水剂>水料比>表面活性剂。最后,利用Design-Expert软件得出黏液材料的最佳配比为:表面活性剂4%,保水剂0.8%,水料比10∶1。为验证动态密封黏液型材料的高效性,选取漳村煤矿进行现场实验,并对30天内瓦斯抽采数据进行统计分析。实验表明:试验孔瓦斯抽采浓度比传统黏液材料封孔提高了24.57%,瓦斯抽采时间延长了1.5倍,瓦斯抽采流量得到显著提升,达到了煤矿瓦斯高效抽采的目的。

In order to solve the problem that the mucilage material used in dynamic sealing method cannot effectively block the gas leakage channel of coal rock,the modification of sodium bentonite was studied.With sodium bentonite as the base material and sodium carboxymethyl cellulose(CMC)as the binder,polyacrylamide(PAM)as the water-retaining agent and sodium fatty acid methyl sulfonate(MES)as the additives,a dynamic sealing mucous material attached to the coal wall was developed.The effects of the content of surfactant,water-retaining agent and water-solid ratio on the viscosity and fluidity of materials were investigated by single factor experiments,and the variation trend of each dependent variable with independent variable was obtained.On the basis of this experiment,according to the principle of orthogonal experiment,17 groups of ratio experiments with three factors and three levels were designed,and the viscosity of the 17 groups of experiments was statistically analyzed.According to the viscosity of the material obtained within 30 min,the fitting and regression analysis were carried out,and the fitting quadratic regression equation was obtained.Secondly,variance analysis,contour analysis and response surface analysis were used to judge the significance of the interaction of each factor on the experimental results.The analysis showed that the order of significance of the three factors was:water-retaining agent>water-solid ratio>surfactant.Finally,the optimal ratio of mucous material was obtained by using Design-Expert software:4%surfactant,0.8%water-retaining agent and 10∶1 water-material ratio.In order to verify the high efficiency of dynamic sealing mucilage material,field experiment was carried out in Zhangcun Coal Mine,and statistical analysis was made on the data of gas extraction within 30 days.The experimental results show that the gas extraction concentration of the test hole is increased by 24.57%compared with that of the traditional slime material sealing hole,the gas extraction time is prolonged by 1.5 times,and the gas extraction flow rate is significantly increased,thus achieving the purpose of efficient gas extraction in coal mine.