疏松砂岩多层气藏钻井难点及优化对策
Drilling Difficulties and Optimization Countermeasures of Multilayer Gas Reservoirs in Unconsolidated Sandstone
宋维春 1张闯 1赵维超 1邢星 1黄成贵1
作者信息
- 1. 中国石油青海油田公司钻采工艺研究院,甘肃敦煌 736202
- 折叠
摘要
涩北气田是典型的疏松砂岩气藏,具有纵向气层多、储层疏松非均质性强、敏感性矿物多等地质特征.利用大量的气藏地质、动态监测和钻录测资料,剖析钻井施工中存在的问题和技术难点,开展优化对策研究.结果表明:1)储层疏松、薄互层多、矿化度高和开发后期纵向压力系统紊乱是影响优快钻井施工的主要因素;2)针对钻井施工中井控风险大、井身结构确定困难的问题,通过优化研究确定了不同气藏、不同深度、不同部位井的井身结构;3)针对比较突出的井漏问题,研发适宜的低伤害、能有效抑制黏土膨胀的MEG(甲基葡萄糖苷)钻井液体系;4)针对固井质量难以保证的问题,采用纳米基低密度水泥浆、工艺改进和精细施工等措施得以解决.认为,优化技术对策应用效果明显,解决了钻井技术难点,实现了疏松砂岩多层气藏快速安全钻井.
Abstract
Sebei gas field is a typical unconsolidated sandstone gas reservoir with many longitudinal gas layers,strong loose heterogeneity and sensitive minerals.A large number of gas reservoir geological,dynamic monitoring and drilling data were used to analyze the existing problems and technical difficulties in drilling construction and carry out optimization countermeasures.The results show that:1)the porosity of the reservoir,multiple thin interbeds,high salinity and the disturbance of the longitudinal pressure system in the late stage of development are the main factors affecting the construction of the optimal drilling;2)aiming at the problems of large well control risk and difficult well structure determination in drilling construction,the well structure of different gas reservoirs,different depths and different positions is determined through optimization study;3)in view of the prominent leakage problem,the suitable MEG drilling fluid system with low damage and effective inhibition of clay expansion was developed;4)to solve the problem that cementing quality is difficult to guarantee,measures such as nano-low density cement slurry,process improvement and fine construction are adopted.It is concluded that the application effect of the optimization technical countermeasure is obvious,the difficulty of drilling technology is solved,and the fast and safe drilling of unconsolidated sandstone multi-layer gas reservoir is realized.
关键词
疏松砂岩气藏/井身结构/固井质量/井漏/低密度水泥浆Key words
loose sandstone gas reservoir/well body structure/cementing quality/well leakage/low density cement slurry引用本文复制引用
出版年
2024
NETL
NSTL
维普
万方数据