摘要
准噶尔盆地南缘区块古近系、白垩系、侏罗系等地层,压力系数高达2.40~2.65 g/cm^(3),为了保障异常高压地层的安全钻进,急需研发性能优异的超高密度油基钻井液。使用环境扫描电子显微镜和激光粒度分析仪,分析了普通重晶石、微粉锰矿和微粉重晶石的微观形态和粒度分布。分析了微粉加重剂降低钻井液黏度的原理,实验评价出配制超高密度油基钻井液加重剂最佳复配方案为普通重晶石∶微粉锰矿=7∶3。优化出超高密度油基钻井液的配方,评价其高温沉降稳定性能、抗水污染性能。实验结果显示,配制的超高密度油基钻井液具有好的高温沉降稳定性,静恒温24 h,上下密度差值为0.01~0.02 g/cm^(3),静恒温120 h,上下密度差值为0.10~0.14 g/cm^(3),上下密度差值小;具有好的抗水污染性能,能抗15%以内的水污染。现场应用表明:密度为2.65 g/cm^(3)的超高密度油基钻井液在钻进过程中,全程钻井液性能表现良好,井下安全正常。
The pressure coefficient of the Paleogene,Cretaceous and Jurassic systems in the south rim of the Junggar Basin is in a range of 2.40-2.65 g/cm^(3).An ultra-high density oil base drilling fluid with excellent performance is in urgent need to ensure safe drilling in this area.Using environmental scanning electron microscope and laser particle size analyzer,the micro morphology and particle size distribution of the common barite,micronized manganese ore and micronized barite were analyzed.The principles of reducing the viscosity of drilling fluids with micronized weighting agents are also analyzed.A mixture of different weighting agents in optimum ratio for formulating ultra-high density oil base drilling fluids was made through laboratory experiment,that is,common barite:micronized manganese ore=7∶3.An ultra-high density oil base drilling fluid was formulated and its high temperature settling stability and water contamination resistance were evaluated.The experimental results showed that the ultra-high density oil base drilling fluid has good high temperature settling stability;after standing for 24 h at a constant temperature,the difference between the density of the top and the density of the bottom of the oil base drilling fluid was 0.01-0.02 g/cm^(3).After standing for 120 h at a constant temperature,the difference between the density of the top and the density of the bottom of the oil base drilling fluid was 0.10-0.14 g/cm^(3).The oil base drilling fluid is resistant to the contamination of 15%water invasion.Field operation showed that a 2.65 g/cm^(3) ultra-high density oil base drilling fluid manifested itself good performance in the whole drilling process,with no troubles encountered downhole.
作者
刘政
李俊材
徐新纽
LIU Zheng;LI Juncai;XU Xinniu(Drilling Fluid Technology Service Company,CNPC Chuanqing Drilling Engineering Company Limited,Chengdu,Sichuan 610051;CNPC Exploration Department of Xinjiang Oilfield Branch,Kelamayi,Xinjiang 834000)
出处
《钻井液与完井液》
CAS
北大核心
2020年第6期715-720,共6页
Drilling Fluid & Completion Fluid
基金
中国石油天然气集团有限公司科学研究与技术开发项目钻完井技术集成试验与推广应用“重点上产地区钻井液评估与技术标准化有形化研究”(2019D-4226)。
关键词
微粉锰矿
微粉重晶石
超高密度
油基钻井液
高温沉降稳定性
Micronized manganese ore
Micronized barite
Ultra-high density
Oil base drilling fluid
High temperature settling stability
