【摘要】 针对织金煤层特点,开发出一种可以提高煤岩疏水性及井壁稳定性的复合表面活性剂,并对各项性能进行了综合评价。试验结果表明:该复合表面活性剂能够有效减小煤岩与钻井液的界面张力,提高与煤岩的接触角,使煤岩与清水的接触角由65.5°增至124°,增幅为89.31%。同时能够有效地阻缓液相侵入煤岩中,降低对煤岩的压力传递,且与水基钻井液具有较好的配伍性。此外,该复合表面活性剂还能够有效改变织金煤岩表面的润湿性,煤岩表面形成疏水层,降低水相通过裂隙进入岩样的内部。更多还原

【Abstract】 According to the characteristics of Zhijin coal measure strata, a kind of composite surfactant is developed which can improve the hydrophobicity of coal rocks and the wellbore stability, and the comprehensive evaluation of the properties is carried out. The results show that the composite surfactant can effectively reduce the interfacial tension between coal rocks and drilling fluid, improve the contact angle with coal rocks, and increase the contact angle between coal rocks and clean water from 65.5° to 124° with an increase of 89.31%. At the same time, it can effectively prevent the invasion of liquid phase into coal rocks, reduce the pressure transmission to coal rocks, and has good compatibility with water-based drilling fluid. In addition, the composite surfactant can effectively change the wettability of the surface of Zhijin coal rocks, form hydrophobic layer on the surface of coal rocks, and reduce the water phase entering into the interior of coal rocks through cracks.更多还原