莺歌海盆地抗高温高密度钻井液技术  

High Temperature High Density Drilling Fluid Technology for Yinggehai Basin

作　　者：张群 刘建全 蒋官澄[2] 王东超[1] 

机构地区：[1]中海油能源发展股份有限公司工程技术分公司中海油实验中心,广东湛江 [2]中国石油大学(北京)石油工程学院,北京

出　　处：《钻井液与完井液》2015年第5期27-31,102-103,共5页Drilling Fluid & Completion Fluid

基　　金：国家“863”项目“海上大位移井水平井钻井液关键技术研究”(2012AA091502);国家“863”项目“致密气藏高效钻井技术研究”(2013AA064803);国家自然科学石油化工联合基金重点支持项目(U1262201);国家自然科学基金面上项目(51474231);中石油重点项目(2014D-4407);中石油新方法新技术项目(2014A-4212)

摘　　要：南海莺歌海盆地储层具有高温高压特征,主要储层温度范围为186～218℃,地层压力系数范围为1.6～2.4,现用的水基钻井液抗温达到180℃,密度能够达到2.0 g/cm3,存在抗温性能不足,在200℃老化后钻井液增稠严重,密度难以达到地层要求的压力范围,对储层损害程度较严重等问题。结合该区域地质概况和储层损害机理分析,对钻井液进行了优化,加入超细碳酸钙和广谱油膜封堵剂,形成良好泥饼和致密的封堵薄膜;加入表面活性剂,改变孔隙岩石的表面性质,防止水锁现象的发生;加入白油和表面活性剂提高体系抗温性。优化的抗高温高密度水基钻井液在200℃条件下性能良好,密度可达到2.2 g/cm3,能够满足井下安全生产需要;钻井液具有良好的封堵性和防水锁能力,渗透率恢复值达90%左右;具有一定的抗CO2污染能力。Reservoir formations in Yinggehai Basin are of high temperature(186–218 ℃) and high pressure(coefficient of formation pressure:1.6–2.4). Failure to maintain stable properties of the drilling fluids currently used at high temperature leads to high viscosity which in turn makes weighting of the drilling fluids very difficult. Poor performance of the drilling fluids also caused damage to reservoirs. Optimization has been done to the drilling fluids recently based on the understanding of the formation geology and analysis of the mechanism of formation damage. Ultra-fine calcium carbonate powder and a broad spectrum oil-film temporary sealing agent were added to form high-quality mud cake and tough thin-film. Surfactants were used to improve the surface properties of formationrocks, in an effort to prevent water block from happening. White oil, together with the surfactants, contributes to the temperature stability of the drilling fluids. The optimized formulation remains stable at 200 ℃ and 2.2 g/cm3, satisfying the needs for drilling operation. Cores flooded with this drilling fluid have permeability return of 90%. It is also resistant to CO2 contamination.

关 键 词：高温钻井液 高密度钻井液 防止地层损害 钻井液配方 莺歌海盆地 

分 类 号：TE254.3[石油与天然气工程—油气井工程]