【摘要】 在应用中,分散型钻井液存在"性能稳定"和"井壁稳定"矛盾要求及钻井液的Zeta电位与所钻地层电性不匹配的问题。具有抑制性的阳离子水基钻井液能有效抑制泥页岩水化分散的问题,但出现阳离子型处理剂和阴离子型处理剂不相容的问题。从理论和试验分析了将高负Zeta电位的钠基膨润土改造成"零电位"土的途径。由正交试验结果确定,以HEC、PEO和AlCl3为膨润土电性改变剂形成的膨润土-水分散体系,可以配成符合钻井液性能要求的体系。以此为基础,不使用阴离子型处理剂,只使用阳离子型、非离子型和高价无机盐作处理剂,优选出了"零电位"水基钻井液的基本配方。更多还原

【Abstract】 Problems of contradictory between performances stability and wellbore stability,and incompatible zeta potential between drilling fluid and formations are encountered in dispersive drilling fluid system.The experimental results show that the negative zeta potential of formation rocks are not high,and the cationic water base drilling fluid system can inhibit hydration and dispersion of mud shale stone,however,problems are found in incompatible between cationic agents and anionic agents.In this paper,the probabilities are analyzed that are changing from high negative zeta potential sodium bentonite to "zero potential" bentonite,changing from "anionic suspension" to "cationic suspension" of bentonite-water dispersion system,displacing anionic agents by cationic,nonionic and electrolyte agents,and preparing "zero potential" water base drilling fluid.更多还原