Experimental Study on Oil Base Mud Loss Control with Gel LCM
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摘要: 钻井工程中使用油基钻井液一旦发生严重漏失,现场处理更困难,且目前尚未形成油基钻井液的高效堵漏技术,因此提出并探讨了油基钻井液用凝胶堵漏方法。研选结果表明,胶凝剂NJZ能够在柴油中具有良好的溶解性,且成胶性能较好,胶凝剂NJZ与交联剂JLJ成胶效果最好,而其与交联剂AlCl3·6H2O、AlCl3·6H2O和NaOH复配的成胶效果较差,无法满足要求,胶凝剂NJZ浓度为10.0%、交联剂JLJ浓度为4.0%时,使用乳化剂EHJ的交联效果最好,凝胶强度最高。用正交实验法优化了凝胶堵漏体系配方,分析了温度、pH值、剪切作用等对成胶性能的影响。通过填砂管室内实验评价表明,采用双液注入方法,结合多次挤注工艺,相对水基凝胶堵漏体系,新研制的油基凝胶具有更强的堵漏作用效果,且具有良好的抗温性,在120℃下仍具有较高的凝胶强度,承压能力梯度达到1.05 MPa/m。Abstract: Loss of oil base mud downhole is diffcult to stop in feld operation and causes great economic loss. An oil base mud loss control method is presented to effciently control oil base mud loss. This method uses gel lost circulation material (LCM) to control oil base mud loss. In selecting additives for gel LCM, a gelling agent NJZ was found to have good solubility in diesel oil and had good gelling capacity. NJZ reacted very well with a crosslinking agent JLJ to form high quality gels. It did not form good gel with the crosslinking agent AlCl3f 6H2O and NaOH. Highest gel strength was obtained by reacting a 10.0% NJZ solution with 4.0% crosslinking agent solution under the action of an emulsifer EHJ. The formulation of the gel LCM was optimized by orthogonal experiment, and the effects of temperature, pH and shearing on gel strength were analyzed. Laboratory experiment has shown that the gel LCM can be used the way cement LCM is used, and can be squeezed in multiple times. Compared with water base gel LCM, this oil base gel LCM worked better in stopping mud loss and has good high temperature stability; it had high gel strength even at 120℃, and was able to tolerate a pressure gradient of 1.05 MPa/m.
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Key words:
- Downhole mud loss /
- Oil base drilling fluid /
- Gel LCM /
- Pressure bearing capacity /
- Drilling engineering
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[1] WANG H, SWEATMAN R, ENGELMAN B, et al. Best practice in understanding and managing lost circulation challenges[C].SPE 95895, 2008. [2] GUO H, VONCKEN J, OPSTAL T, et al.Investigation of the mitigation of lost circulation in oil-based drilling fluids by use of gilsonite[C].SPE 157751, 2012. [3] 刘均一, 邱正松, 罗洋, 等. 油基钻井液随钻防漏技术实验研究[J]. 钻井液与完井液, 2015, 32(5):10-14.LIU Junyi, QIU Zhengsong, LUO Yang, et al. Experimental study on lost circulation prevention of oilbased drilling fluid[J].Drilling Fluid & Completion Fluid, 2015, 32(5):10-14. [4] 王中华. 国内外油基钻井液研究与应用进展[J]. 断块油气田, 2011, 18(4):533-537.WANG Zhonghua.Research and application progress of oil-based drilling fluid at home and abroad[J].Fault-Block Oil & Gas Field, 2011, 18(4):533-537. [5] NAYBERG T M, PETTY B R.Laboratory study of lost circulation materials for use in both oil-base and waterbase drilling muds[C].SPE14723, 1986. [6] 刘宇凡, 刘滨, 吴林龙. 水泥浆堵漏技术探讨[J]. 钻采工艺, 2014, 37(4):110-112.LI Yufan, LIU Bin, WU Linlong.Discussion on plugging technology of cement slurry[J].Drilling & Production Technology, 2014, 37(4):110-112. [7] 朱涛. 恶性漏失堵漏用特种凝胶评价方法研究[D]. 成都:西南石油大学, 2014. ZHU Tao.Study on evaluation method of special gel for lost circulation[D].Chengdu:Southwest Petroleum University, 2014. [8] 张雪峰. 堵漏凝胶的研究与应用[D]. 长春:吉林大学, 2013. ZHANG Xuefeng.The study and application of polymer gel for loss control[D].Changchun:Jinlin University, 2013. [9] 汪建军. 功能型复合凝胶自适应堵漏技术研究[D]. 成都:四川大学, 2008. WANG Jianjun.Research on automatic lost circulation prevention technology of the functional compound gel[D]. Chengdu:Sichuan University, 2008. -

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