土库曼斯坦亚速尔地区盐膏层及高压盐水层钻井液技术措施

Drilling fluid technology for salt-gypsum zonesand high pressure saltwater zones in Azores Area, Turkmenistan

土库曼斯坦亚速尔哲别油田2230～2860m存在多套盐膏层及高压盐水层,矿化度高、安全密度窗口窄,施工难度极大。研究应用了钙处理的复合盐水钻井液体系,利用对钻井液的钙处理提高了抗高浓度钙镁离子污染的能力,保证了钻井液性能的稳定;应用近平衡压力钻井技术与随钻堵漏技术相结合,使用延时膨胀堵漏技术为主的复合堵漏技术较好地解决了井漏及安全密度窗口窄的难题。现场顺利完成了4口井的施工,为以后该地区钻井施工的顺利进行提供了技术保障。

The interval between 2230 m and 2860 m of Zhebie Oilfield in Azores of Turkmenistan is difficult to drill due to manychallenges, such as existence of multiple salt-gypsum zones and high pressure saltwater zones, high salinity and narrow safety pressurewindows. Through researching and applying calcium treated compound saltwater drilling fluid system, anti-pollution capacity againsthigh concentration of Ca^2＋ and Mg^2＋ of drilling fluid is enhanced and its stability is guaranteed. Combined near-balance pressure drillingwith plugging while drilling, technical problems of lost circulation and narrow safety pressure windows were resolved by using timelagged swelling compound plugging technology. As a result of above technologies, four wells are finished successfully, providing technologicalguarantee for future drilling in the area.