不同含量纳米流体改性煤粉润湿性能研究

Wettability of Modified Coal Dust of Nanofluids with Different Concentrations

针对煤粉的润湿性较差、水-煤结合速度慢,井下水力排渣效果不明显等问题,选择二氧化硅(SiO_(2))纳米流体这一具有润湿岩体、改善煤体润湿性等特殊性质的新型液体材料,探究其作为排渣介质,强化煤粉表面润湿性,提升水力排渣能力的效果。选取去离子水和纳米流体进行煤粉润湿性实验,改变纳米流体质量分数、煤粉粒径和润湿剂-煤粉配比,采用接触角测量仪等设备量化煤粉表面润湿性,探究了SiO_(2)纳米流体强化钻孔排渣能力的效果及影响因素。结果表明,随着SiO_(2)纳米流体的质量分数增加,煤粉表面接触角逐渐减小,最低可达21.64°,使煤粉从油湿性转化为水湿性;分析过程中引入强化值与强化率,发现SiO_(2)纳米流体煤粉润湿值约为去离子水的8.5倍,强化率最高可达70.8%。本研究为钻孔排渣介质的选择提供了方向。

Aiming at the problems,including poor wettability of coal dust,slow water-coal combination,and ineffectual hydraulic slag removal,we chose silica(SiO_(2))nanofluid,a new liquid material with special properties of wetting rock body and improving wettability of coal body,to investigate its effect of strengthening the surface wettability of coal dust,and enhancing the hydraulic slag removal ability as a slag removal medium.Deionized water and nanofluids were selected to carry out coal dust wettability experiments:by changing the mass fraction of nanofluids,the particle size of coal dust and the ratio of wetting agent to coal dust,and quantifying the surface wettability of coal dust by contact angle meter and other equipment,the study explored the effect and influencing factors of SiO_(2) nanofluid to strengthen the borehole slagging capability.The results showed that with the increase of the mass fraction of SiO_(2) nanofluid,the contact angle of the coal dust surface gradually decreased to 21.64°,which transformed the coal dust from oil-wettability to water-wettability.In addition,by introducing the enhancement value and enhancement rate in the analytical process,it was found that the wetting value of coal dust with SiO_(2) nanofluid was about 8.5 times that of deionized water,and the reinforcement rate was up to 70.8%.This study could provide a direction for the selection of borehole slagging media.