低油水比油基钻井液体系研究
Research on low oil-water ratio of oil-based drilling fluid system
韩秀贞1
作者信息
- 1. 页岩油气富集机理与有效开发国家重点实验室,北京 102206;中国石化石油工程技术研究院有限公司,北京 102206
- 折叠
摘要
现阶段国内大量应用的油基钻井液体系油水比居高不下,且由于部分处理剂性能欠佳导致在钻井液体系中用量过大,两者叠加为降低油基钻井液体系综合成本带来极大困难.为此,提出了低油水比油基钻井液体系设计思路,并以此为指导研选了油基钻井液体系关键处理剂,通过配伍性实验构建了低油水比油基钻井液体系配方,并开展了现场应用.以保障在良好的乳化稳定性、流变性和较强的随钻封堵性基础上有效降低油水比为整体思路,研制了多活性点新型乳化剂,增加了分子内活性吸附基团的数量,在低油水比的情况下表现出良好的乳化稳定性和流变性;优选了具有良好增黏提切效果且可降低滤失量的有机土、具有良好降滤失效果的降滤失剂、具有改善流变性且提高乳化稳定性的流型调节剂,以 3 种处理剂为核心构建了低油水比油基钻井液体系;该体系在 70/30 的油水比条件下老化前后破乳电压＞1 000 V,在60/40 的油水比条件下老化前后破乳电压＞500 V,动塑比均＞0.40,具有良好的乳化稳定性和流变性;低油水比油基钻井液体系在 12 口页岩水平井开展了现场应用,钻井液体系性能稳定、井眼净化效果良好,且乳化稳定性可控,大幅节约了基础油的用量,显著降低了油基钻井液体系的成本.
Abstract
At present,the oil-water ratio of oil-based drilling fluid system widely used in China remains high,and due to the poor performance of some treatment agents,the amount used in some drilling fluid systems is too large.The combination of the two poses great diffi-culties in reducing the comprehensive cost of oil-based drilling fluid system.To this end,a design concept for a low oil-water ratio of drilling fluid system was proposed,and based on this,key treatment agents for oil-based drilling fluid system were selected.Through compat-ibility experiments,a low oil-water ratio of drilling fluid system formula was constructed,and on-site applications were carried out.The overall idea is to effectively reduce the oil-water ratio on the basis of ensuring good emulsification stability,rheological properties,and strong plugging while drilling,a new type of emulsifier with multiple active points has been devel-oped,which increases the number of active adsorption groups within the molecule and ex-hibits good emulsification stability and rheological properties under low oil-water ratio.A low oil-water ratio diesel based drilling fluid system was constructed with three treatment agents as the core,including organic soil with good viscosity increasing and shear reducing effects,filter loss reducing agents with good filter loss reducing effects,and flow pattern regulators with improved rheological properties and emulsion stability.The system has a demulsification voltage greater than 1 000 V before and after aging under an oil-water ratio of 70/30,and greater than 500 V before and after aging under an oil-water ratio of 60/40.The ratio of yield stress to plastic viscosities greater than 0.40,indicating good emulsification stability and rhe-ological properties.Low oil-water ratio of oil-based drilling fluid system has been applied on-site in 12 shale horizontal wells.The drilling fluid system has stable performance,good well-bore purification effect,and controllable emulsification stability,leading to greatly saving the amount of base oil and significantly reducing the cost of oil-based drilling fluid system.
关键词
油基钻井液/低油水比/乳化剂/乳化稳定性/流变性Key words
oil-based drilling fluid/low oil-water ratio/emulsifier/emulsification stability/rheological properties引用本文复制引用
基金项目
国家自然科学基金企业创新发展联合基金(U19B6003-05)
中国石化重点实验室项目(KLP23021)
出版年
2024
NETL
NSTL
万方数据