无固相弱凝胶钻开液在污水回注井中的研究与应用  

Research and Application of Solid Free Weak Gel Drilling Fluid in Wells with Produced Water Reinjection in CFD Oilfield

作　　者：王昆剑 李进[1,2] 刘鹏飞 王攀 王庆 何斌 柏晓超 Wang Kunjian;Li Jin;Liu Pengfei;Wang Pan;Wang Qing;He Bin;Bai Xiaochao(State Key Labratory of Offshore Oil Exploitation,Tianjin 300459;Tianjin Branch of CNOOC L td.,Tianjin 300459;Engineering Technology Company of CNOOC Energy Technology&Services Limited,Tianjin 300459;China Oilfield Services Co.,Ltd.,Tianjin 300459)

机构地区：[1]海洋石油高效开发国家重点实验室,天津300459 [2]中海石油(中国)有限公司天津分公司,天津300459 [3]中海油能源发展股份有限公司工程技术分公司,天津300459 [4]中海油田服务股份有限公司,天津300459

出　　处：《中外能源》2021年第5期44-48,共5页Sino-Global Energy

基　　金：“十三五”国家重大科技专项“渤海油田高效开发示范工程”(编号:2016ZX05058)。

摘　　要：为了满足曹妃甸油田储层大斜度回注井对钻开液防塌抑制性和储保性能的要求,本文以渤海油田常用无固相弱凝胶EZFLOW钻开液体系为基础,通过采用无机盐复配方式提高体系的抑制性,同时优化体系颗粒级配形成屏蔽暂堵层,最大限度地保护储层。优化后的钻开液体系配方为0.2%Na2CO3+0.2%NaOH+0.4%PF-EZVIS+1.5%PF-EZFLO+8%PF-EZCARB+5%KCl+NaCl,优化后的钻开液体系具备易降解、逆向不需化学解堵、正向酸化可完全降解的能力,储层保护效果优异。优化后的钻开液体系在曹妃甸油田大斜度污水回注井中首次成功应用2口井,回注量分别高达12516m^(3)/d和14155m^(3)/d,超出配注量9.4%和23.7%,满足了大斜度裸眼井对钻开液储保性能的要求。应用表明,该技术打破了以往定向井无法用EZFLOW体系的惯例,有效保障了污水回注井日回注量超出10000m^(3)的要求,为曹妃甸油田群的有效开发提供了技术保障,具有良好的推广前景。In order to satisfy the requirements of inhibitive capacity and reservoir protection of drilling fluid for the high-deviated reinjection wells in Caofeidian Oilfield,EZFLOW solid free weak gel drilling fluid system commonly used in the Bohai Oilfield is compounded with inorganic salt to improve the inhibition of the system,and the grain composition of the system is optimized to form temporary plugging formations for reser-voir protection maximally.The optimized drilling fluid system is formulated as 0.2% Na2CO3+0.2% NaOH +0.4%PF-EZVIS+1.5%PF-EZFLO+8%PF-EZCARB+5% KCl+NaCl.The optimized drilling fluid system has the capability of easy degradation,no chemical plugging removal on the reverse and complete degradation while forward acidification.Effect of reservoir protection is excellent.The optimized drilling fluid system was successfully applied to two high-deviated wells with produced water reinjection in Caofeidian Oilfield for the first time,and the injection volume was up to 12516 m3/d and 14155 m3/d,exceeding the injection allocation by 9.4%and 23.7% respectively,which met the requirements of reservoir protection of the drilling fluid for the high-deviated open hole wells.The application shows that this technology breaks the traditional practice that EZFLOW system cannot be used in directional wells,and effectively guarantees the requirement that the daily injection of the wells with produced water reinjection exceeds 10000 m3.It provides technical support for the effective development of Caofeidian Oilfield Group,and has a good promising development.

关 键 词：无固相 钻开液 污水回注 大斜度井 渤海油田 

分 类 号：TE52[石油与天然气工程—油气田开发工程]