西南石油大学学报(自然科学版) ›› 2021, Vol. 43 ›› Issue (3): 81-92.DOI: 10.11885/j.issn.16745086.2020.12.20.02

• 石油与天然气工程 • 上一篇    下一篇

颗粒形状对裂缝封堵层细观结构稳定性的影响

康毅力1, 经浩然1, 许成元1,2, 闫霄鹏1, 商翔宇1,3   

  1. 1. 油气藏地质及开发工程国家重点实验室·西南石油大学, 四川 成都 610500;
    2. 中国石油大学(华东)石油工程学院, 山东 青岛 266580;
    3. 深部岩土力学与地下工程国家重点实验室·中国矿业大学, 江苏 徐州 221116
  • 收稿日期:2020-12-20 发布日期:2021-06-22
  • 通讯作者: 康毅力,E-mail:cwctkyl@163.com
  • 作者简介:康毅力,1964年生,男,汉族,天津蓟县人,教授,博士生导师,主要从事储层保护理论与技术、非常规天然气和油气田开发地质方向科研与教学。E-mail:cwctkyl@163.com
    经浩然,1996年生,男,汉族,四川南充人,硕士研究生,主要从事工作液漏失控制、储层保护理论与技术方向的研究工作。E-mail:834267951@qq.com
    许成元,1988年生,男,汉族,河北沧州人,副教授,博士,主要从事储层保护理论与技术、工作液漏失控制、颗粒物质力学与颗粒流领域的科研与教学工作。E-mail:chance_xcy@163.com
    闫霄鹏,1992年生,男,汉族,河南许昌人,博士研究生,主要从事储层保护理论与技术、工作液漏失控制等方向的科研工作。Email:lcm_yxp2017@126.com
    商翔宇,1977年生,男,汉族,河南汝阳人,副教授,博士,主要从事深部土、冻土力学以及相关岩土工程的研究工作。E-mail:xyshang@cumt.edu.cn
  • 基金资助:
    国家自然科学基金(51604236);四川省科技计划项目(2018JY0436);油气藏地质及开发工程国家重点室开放基金(PLN201913)

Effects of Particle Shape on the Meso-structure Stability of Fracture Plugging Zones

KANG Yili1, JING Haoran1, XU Chengyuan1,2, YAN Xiaopeng1, SHANG Xiangyu1,3   

  1. 1. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan 610500, China;
    2. School of Petroleum Engineering, China University of Petroleum(East China), Qingdao, Shandong 266580, China;
    3. State Key Laboratory of Geomechanics & Deep Underground Engineering, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China
  • Received:2020-12-20 Published:2021-06-22

摘要: 裂缝封堵层结构与裂缝性地层封堵承压能力存在密切联系,并常常决定着钻井防漏堵漏作业的成败。为研究颗粒形状对裂缝封堵层细观结构稳定性的影响,选用5种不同形状的聚碳酸酯颗粒,模拟压力波动情况,开展裂缝封堵层剪切失稳的二维光弹实验,获得裂缝封堵层细观结构演化过程中的光弹图像,并运用Matlab处理光弹图像,析出强力链占比和强力链方位参数。实验结果表明,在以圆形颗粒为基础的裂缝封堵层中,加入椭圆形、正三角形、正方形和矩形颗粒能够使裂缝封堵层力链结构更加多样,环状力链增加;当存在压力波动时,长条状颗粒对裂缝封堵层细观结构稳定性贡献优于正多边形颗粒,棱角状颗粒相比圆弧状颗粒更能分散力的方向,促使封堵层细观结构更趋稳定。研究发现,刚性堵漏材料中棱角、长条状颗粒占比40%左右时,堵漏效果最佳。基于该认识,调整了钻井防漏堵漏浆配方,增强了裂缝封堵层承压能力,现场试验一次堵漏成功。

关键词: 钻井, 防漏堵漏, 裂缝封堵层, 颗粒物质, 几何形状, 细观结构, 力链, 光弹实验

Abstract: The stability of fracture plugging zone has a great impact on the lost circulation control effect in fractured reservoirs. To investigate the effect of particle shape on the stability of the mesoscopic structure of fracture plugging zone, polycarbonate particles with five different shapes are chosen for the photoelastic experiment. Photoelastic images of the simulated fracture plugging zone under shear loads are obtained to characterize the mesoscopic structure evolution of fracture plugging zone. The key parameters for the mesoscale structure characterization of fracture plugging zone are proposed based on the mean square gray gradient method, including the strong force chain and its orientation. The experimental results show that adding elliptic, equilateral triangular, square, and rectangular particles into fracture plugging zone formed by circular particles can make the structure of the force chain more varied and increase ring-like strong force chain. The contribution of long strip particles to the stability of the meso-structure of fracture plugging zone is larger than the regular polygon particles as the pressure fluctuation applies on the fracture plugging zone. The angular particles disperse the direction of force better than the circular ones, which makes the meso-structure of fracture plugging zone more stable. The effect of lost circulation control is improved when the proportion of angular and long strip particles is about 40% of rigid lost circulation materials (LCMs). Based on this understanding, the prescriptives of lost circulation control is adjusted, and the bearing capacity of the fracture plugging zone is enhanced. Field test of lost circulation control are successful once.

Key words: drilling, lost circulation control, fracture plugging zone, granular matter, geometric shapes, mesoscopic structure, force chain, photoelastic experiment

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