Mechanisms of Lost Circulation and Technologies for Mud Loss Prevention and Control in Shale Oil Drilling
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摘要: 针对页岩油钻井过程中漏失频发的问题,以济阳坳陷页岩油开发为例,分析了页岩油钻井油基钻井液的漏失机理。分析发现,页岩油藏天然断裂系统发育,容易发生漏失;页岩脆性强,表面油润湿,长水平段压耗大,易产生诱导裂缝漏失;油基钻井液使堵漏材料摩擦系数降低,防漏堵漏难度大。基于页岩油油基钻井液的漏失机理,对弹性孔网材料进行了表面改性处理,优选了填充材料,研制了一袋式堵漏剂,并开展了室内长裂缝封堵评价实验和现场试验。结果表明,研制的一袋式堵漏剂封堵效果好,2 mm×1 mm长裂缝承压强度达10 MPa,现场堵漏一次成功,较好地解决了页岩油油基钻井液漏失难题,为保障页岩油藏的优质快速钻井提供了技术支持。Abstract: Mechanisms of loss of oil based drilling fluids were analyzed taking the shale oil development in the Jiyang Depression as an example to solve the frequent occurrence of mud losses in shale oil development. The analytical results have shown that natural fractures are highly developed in shale oil reservoir formations, and this is one reason why the mud is easy to lose in shale oil drilling. The shales drilled are very brittle, and their surfaces are oil wet, pressure losses in long horizontal sections are therefore high, resulting in induced fractures into which the mud is lost. Lost circulation materials (LCM) in oil based drilling fluids have low friction coefficients, making it difficult to control the mud losses. Based on the studies on the mechanisms of mud losses occurred in shale oil drilling, a one-bag lost circulation material made from a surface-modified elastic mesh material and an optimized filling material. Laboratory long-fracture sealing and plugging experiment and field application have shown that the one-bag LCM has good sealing and plugging capacity; fractures of 2 mm × 1 mm has pressure bearing capacity of 10 MPa after being plugged with the LCM. Mud losses in field operations were brought under control in the first try of the LCM. The application of the one-bag LCM helped solve the losses of oil based drilling fluids in shale oil drilling, providing a technical support to the safe and fast drilling in shale oil reservoirs.
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表 1 不同堵漏材料的目数与粒径分布
代号 HFD-2 HFD-3 HFD-4 HFD-5 RFD-2 RFD-3 RFD-4 目数 10~20 20~40 40~80 80~160 10~20 20~40 40~80 粒径/mm 1.7~0.83 0.83~0.38 0.38~0.18 0.18~0.096 1.7~0.83 0.83~0.38 0.38~0.18 表 2 楔形长裂缝封堵实验配方(2 mm×1 mm)
编号 不同堵漏材料的占比/% HFD-2 HFD-3 HFD-4 HFD-5 RFD-2 RFD-3 RFD-4 FFD-2 IWN-1 1# 1 3 3 2 2# 2 3 3 2 3# 3 3 3 2 4# 4 3 3 2 5# 5 3 3 2 6# 4 3 3 2 1 7# 4 3 3 2 2 8# 4 3 3 2 1 1 9# 4 3 3 2 1 1 1 10# 4 3 3 2 1 1 1 2 11# 4 3 3 2 1 1 1 3 12# 4 3 3 2 1 1 1 5 13# 3 4 2 3 2 1 1 3 0.04 14# 3 4 2 3 2 1 1 3 0.08 15# 3 4 2 3 2 1 1 3 0.12 表 3 楔形长裂缝封堵实验结果(2 mm×1 mm)
编号 封堵区域
位置/mm封堵区域
厚度/mm承压能力/
MPa漏失量/
mL1# 全漏失 2# 985~995 10 3 355 3# 990~1000 10 3.5 345 4# 975~995 20 4 350 5# 封门 6# 920~955 35 5 300 7# 封门 8# 915~940 25 7 270 9# 910~945 35 7 245 10# 850~900 50 8 200 11# 810~875 65 8.5 170 12# 封门 13# 765~830 65 9 145 14# 745~815 70 10 125 15# 封门 -
[1] 孙焕泉. 济阳坳陷页岩油勘探实践与认识[J]. 中国石油勘探,2017,22(4):1-14.SUN Huanquan. Exploration practice and cognitions of shale oil in Jiyang depression[J]. China Petroleum Exploration, 2017, 22(4):1-14. [2] 宋明水. 济阳坳陷页岩油勘探实践与现状[J]. 油气地质与采收率,2019,26(1):1-12. doi: 10.13673/j.cnki.cn37-1359/te.2019.01.001SONG Mingshui. Practice and current status of shale oil exploration in Jiyang depression[J]. Petroleum Geology and Recovery Efficiency, 2019, 26(1):1-12. doi: 10.13673/j.cnki.cn37-1359/te.2019.01.001 [3] 刘振东,刘国亮,高杨,等. 页岩油藏油基钻井液技术[J]. 天然气与石油,2014,32(5):64-67. doi: 10.3969/j.issn.1006-5539.2014.05.017LIU Zhendong, LIU Guoliang, GAO Yang, et al. Technology of oil-based drilling fluid in shale oil reservoir[J]. Natural Gas and Oil, 2014, 32(5):64-67. doi: 10.3969/j.issn.1006-5539.2014.05.017 [4] 袁锦彪,杨亚少,常旭轩,等. 页岩气油基钻井液堵漏技术及其在长宁区块应用[J]. 钻采工艺,2020,43(4):133-136. doi: 10.3969/J.ISSN.1006-768X.2020.04.37YUAN Jinbiao, YANH Yashao, CHANG Xuxuan, et al. Shale gas oil-based drilling fluid plugging technology and its application in Changning block[J]. Drilling & Production Technology, 2020, 43(4):133-136. doi: 10.3969/J.ISSN.1006-768X.2020.04.37 [5] 韩来聚,杨春旭. 济阳坳陷页岩油水平井钻井完井关键技术[J]. 石油钻探技术,2021,49(4):22-28. doi: 10.11911/syztjs.2021073HAN Laiju, YANG Chunxu. Key technologies for drilling and completion of horizontal shale oil wells in the Jiyang depression[J]. Petroleum Drilling Techniques, 2021, 49(4):22-28. doi: 10.11911/syztjs.2021073 [6] 左京杰,张振华,姚如钢,等. 川南页岩气地层油基钻井液技术难题及案例分析[J]. 钻井液与完井液,2020,37(3):294-300. doi: 10.3969/j.issn.1001-5620.2020.03.005ZUO Jingjie, ZHANG Zhenhua, YAO Rugang, et al. Technical difficulties and case study of oil base drilling fluid operation in shale gas drilling in South Sichuan[J]. Drilling Fluid & Completion Fluid, 2020, 37(3):294-300. doi: 10.3969/j.issn.1001-5620.2020.03.005 [7] 吴雄军,林永学,宋碧涛,等. 顺北油气田奥陶系破碎性地层油基钻井液技术[J]. 钻井液与完井液,2020,37(6):701-708. doi: 10.3969/j.issn.1001-5620.2020.06.004WU Xiongjun, LIN Yongxue, SONG Bitao, et al. Oil base drilling fluid technology for drilling broken ordovician formation in Shunbei block[J]. Drilling Fluid & Completion Fluid, 2020, 37(6):701-708. doi: 10.3969/j.issn.1001-5620.2020.06.004 [8] 宁方兴. 济阳坳陷页岩油富集主控因素[J]. 石油学报,2015,36(8):905-914. doi: 10.7623/syxb201508002NING Fangxing. The main control factors of shale oil enrichment in Jiyang depression[J]. Acta Petrolei Sinica, 2015, 36(8):905-914. doi: 10.7623/syxb201508002 [9] 王民,马睿,李进步,等. 济阳坳陷古近系沙河街组湖相页岩油赋存机理[J]. 石油勘探与开发,2019,46(4):789-802. doi: 10.11698/PED.2019.04.19WANG Min, MA Rui, LI Jinbu, et al. Occurrence mechanism of lacustrine shale oil in the Paleogene Shahejie formation of Jiyang Depression[J]. Petroleum Exploration and Development, 2019, 46(4):789-802. doi: 10.11698/PED.2019.04.19 [10] 刘向君 熊健 梁利喜,等. 川南地区龙马溪组页岩润湿性分析及影响讨论[J]. 天然气地球科学,2014,25(10):1644-1652. doi: 10.11764/j.issn.1672-1926.2014.10.1644LIU Xiangjun, XIONG Jian, LIANG Lixi, et al. Analysis of the wettability of Longmaxi Formation shale in the south region of Sichuan basin and its influence[J]. Natural Gas Geoscience, 2014, 25(10):1644-1652. doi: 10.11764/j.issn.1672-1926.2014.10.1644 [11] 王建龙,冯冠雄,刘学松,等. 长宁页岩气超长水平段水平井钻井完井关键技术[J]. 石油钻探技术,2020,48(5):9-14. doi: 10.11911/syztjs.2020086WANG Jianlong, FENG Guanxiong, LIU Xuesong, et al. Key technology for drilling and completion of shale gas horizontal wells with ultra-long horizontal sections in Changning block[J]. Petroleum Drilling Techniques, 2020, 48(5):9-14. doi: 10.11911/syztjs.2020086 [12] 李公让,于雷,刘振东,等. 弹性孔网材料的堵漏性能评价及现场应用[J]. 石油钻探技术,2021,49(2):48-53. doi: 10.11911/syztjs.2021008LI Gongrang, YU Lei, LIU Zhendong, et al. The evaluation and application of lost circulation control by elastic mesh materials[J]. Petroleum Drilling Techniques, 2021, 49(2):48-53. doi: 10.11911/syztjs.2021008 [13] 邱正松,暴丹,李佳,等. 井壁强化机理与致密承压封堵钻井液技术新进展[J]. 钻井液与完井液,2018,35(4):1-6. doi: 10.3969/j.issn.1001-5620.2018.04.001QIU Zhengsong, BAO Dan, LI Jia, et al. Mechanisms of wellbore strengthening and new advances in lost circulation control with dense pressure bearing zone[J]. Drilling Fluid & Completion Fluid, 2018, 35(4):1-6. doi: 10.3969/j.issn.1001-5620.2018.04.001 -