Study on suspension and migration law of proppant in long-distance pipeline for ground-coalmine combined hydraulic fracturing
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摘要: 井地联合压裂是煤矿井下长钻孔分段压裂的发展趋势之一，压裂液经地面压裂泵加压后通过地面贯通井、煤矿井下长输管路进入煤矿井下长钻孔实施大排量压裂。支撑剂在长输管路中的悬浮运移规律对于优化设计加砂参数、避免管路中砂堵具有重要意义。通过室内实验评价压裂液的流变性能和携砂性能；基于欧拉-颗粒流理论构建数值模拟模型，研究水平管内支撑剂悬浮运移规律及其影响因素；探讨压裂液携带支撑剂运移的流态以及临界沉降流速的计算模型。结果表明： 1%降阻剂的加入能够使活性水压裂液黏度提高3~5倍，支撑剂密度越小，压裂液黏度、砂比越高，支撑剂在压裂液中的沉降速度越小；支撑剂在水平管内的流动受到多因素的综合影响，压裂液流速越小，支撑剂密度和粒径越大，支撑剂在管道底部的沉积越严重，携砂效果越差；随着管路直径的增大，管道出口截面支撑剂体积分数最大的位置由管道中下部移动至管道底部，支撑剂流动对于管路的磨损加重；砂比越大，支撑剂间的相互作用越强，压裂液携砂能力降低；优选采用疏浚技术规范推荐的模型计算活性水携砂条件下的支撑剂临界沉降速度，随着管路直径的增大，所需的临界携砂排量呈指数式增大，提高压裂液黏度可降低携砂所需的临界排量。建立的携砂运移临界排量模型和总结的支撑剂运移规律可对管路直径和压裂液排量进行优化匹配，为井地联合压裂施工提供理论支撑。Abstract: Ground-coalmine combined hydraulic fracturing is one of the development trend of staged fracturing of long boreholes in underground coal mines. After the fracturing fluid is pressurized by the ground fracturing pump, it enters the long boreholes in underground coal mines through the through-well and long pipeline to conduct large-pump-rate fracturing. The suspension and migration law of proppant in the long pipeline is of great significance for optimizing the sanding parameters and avoiding sand blockage in the pipeline. The rheological properties and sand carrying properties of fracturing fluid were evaluated by laboratory tests. Then, based on the Euler-particle flow theory, a numerical simulation model was constructed to study the transport law of proppant in horizontal pipe. The flow pattern of fracturing fluid and the calculation model of critical settlement velocity were discussed. The results show that the addition of 1% friction reducer can increase the viscosity of active water fracturing fluid by 3~5 times. The smaller the proppant density, the larger the fracturing fluid viscosity and sand concentration, and the smaller the settling velocity of proppant in fracturing fluid. The flow of proppant in horizontal pipe is affected by many factors. The smaller the flow rate of fracturing fluid, the larger the density and particle size of proppant, and the more serious the deposition of proppant at the bottom of the pipe, and the worse the sand carrying effect is. With the increase of pipeline diameter, the maximum volumetric concentration of proppant at the outlet moves from the middle and lower part of the pipeline to the bottom of the pipeline, and the flow of proppant aggravates the wear of the pipeline. The larger the sand concentration is, the stronger the interaction between proppants is, and the sand carrying capacity of fracturing fluid is reduced. The model recommended by dredging technical specification is preferred to calculate the critical settling velocity of proppant under the condition of active water fracturing fluid. With the increase of pipeline diameter, the required critical sand carrying pump rate increases exponentially. Increasing the viscosity of fracturing fluid can reduce the critical sand carrying pump rate. According to the critical pump rate model of sand carrying migration, the pipeline diameter and fracturing fluid pump rate can be optimized and matched. The research results can provide theoretical support for ground-coalmine combined hydraulic fracturing.
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[1] 孙四清,李文博,张俭,等.煤矿井下长钻孔分段水力压裂技术研究进展及发展趋势[J].煤田地质与勘探,2022, 50(8):1-15 . SUN Siqing, LI Wenbo, ZHANG Jian, et al. Research progress and development trend of staged hydraulic fracturing technology in long-borehole underground coal mine[J].Coal Geology & Exploration, 2022, 50(8):1-15
[2] 贾秉义,李树刚,陈冬冬,等.煤矿井下高压端连续水力加砂压裂增透技术与装备研究[J].煤田地质与勘探,2022,50(8):54-61. JIA Bingyi, LI Shugang, CHEN Dongdong, et al. Study of technologies and equipment of continuous hydraulic sand fracturing for permeability enhancement at high pressure side of coal mine downhole[J].Coal Geology & Exploration, 2022,50(8):54-61.
[3] 刘乐,张俭,方秦月,等.碎软低渗煤层顶板定向长钻孔水力加砂分段压裂工程应用[J].煤炭科学技术,2022,50(8):91-100. LIU Le,ZHANG Jian,FANG Qinyue,et al. Application of hydraulic sand staged fracturing in directional long drilling of roof in broken soft and low permeability coal seam[J].Coal Science and Technology,2022,50(8):91-100.
[4] 张俭,刘乐,赵继展,等.煤层顶板定向长钻孔水力加砂分段压裂技术与装备[J].煤田地质与勘探,2022,50(8):37-44. ZHANG Jian, LIU Le, ZHAO Jizhan, et al. Research on hydraulic fracturing technology and equipment of directional long drilling with sand in coal seam roof[J]. Coal Geology&Exploration, 2022, 50(8):37-44.
[5] 姜在炳,张群,范耀,等. 碎软低渗煤层井上下联合压裂区域瓦斯高效抽采方法:202010380658.5[P]. 2020-08-14. [6] 赵学良.井地联合压裂长钻孔技术实践[J].煤矿安全,2019,50(2):169-172. ZHAO Xueliang. Practice of Integrated Well and Ground Fracturing Long Drilling Technology[J]. Safety in Coal Mines, 2019,50(2):169-172.
[7] Oroskar A R, Turian R M.The critical velocity in pipeline flow of slurries[J].Aiche Journal, 1980, 26(4):550-558.
[8] Gillies R G, Shook C A, XU Jihuai. Modelling heterogeneous slurry flows at high velocities[J]. The Canadian Journal of Chemical Engineering, 2004, 82(5):1060-1065.
[9] Ekambara K, Sanders R S, Nandakumar K, et al.. Hydrodynamic simulation of horizontal slurry pipeline flow using ANSYS-CFX[J]. Industrial & Engineering Chemistry Research, 2009, 48(17):8159-8171.
[10] SWAMY M, DÍEZ N, González TWERDA A. Numerical modelling of the slurry flow in pipelines and prediction of flow regimes[J]. WIT Trans Eng Sci, 2015, 89:311-322.
[11] 温庆志,高金剑,邵俊杰,等.滑溜水压裂支撑剂在水平井筒内沉降规律研究[J].西安石油大学学报(自然科学版),2015,30(4):73-78+8. WEN Qingzhi, GAO Baojian, SHAO Junjie, et al. Study on settlement law of proppant within horizontal wellbore in slickwater fracturing[J]. Journal of Xi'an Shiyou University(Natural Science Edition),2015,30(4):73-78+8.
[12] 吕其超,李兆敏,李宾飞,等.新型聚合物压裂液管内携砂性能研究[J].特种油气藏,2015,22(2):101-104+156. LV Qichao,LI Zhaomin,LI Binfei, et al. Research on Proppant Carrying Capacity of New Polymer Fracturing Fluid in Tube[J]. Special Oil and Gas Reservoirs, 2015,22(2):101-104+156.
[13] 曾思睿,董长银,卫然,等.水平井不同倾角井筒临界携砂流速对比实验及其拟合应用[J].大庆石油地质与开发,2018,37(6):54-59. ZENG Sirui, DONG Changyin, WEI Ran, et al. Comparing experiments and their matching application of the borehole critical sand-carrying velocity in the horizontal well with different pitching angles[J]. Petroleum geology and oilfield development in daqing, 2018,37(6):54-59.
[14] 刘巨保,姚利明,李星月,等.缩扩管内携砂压裂液的压力损失实验与数值模拟[J].石油学报,2019,40(1):86-98. LIU Jubao, YAO Liming, LI Xingyue, et al. Pressure loss experiment and numerical simulation of sand-carrying fracturing fluid in contraction-expansion pipe[J]. ACTA PETROLEI SINICA, 2019,40(1):86-98.
[15] 杨思齐,樊建春,张来斌.高压弯管压裂液两相流模拟及流固耦合分析[J].石油机械,2020,48(3):128-133. YANG Siqi, FAN Jianchun, ZHANG Laibin. Numerical simulation of two-phase flow and analysis of fluid-structure interaction of fracturing fluid in high pressure elbow[J]. CHINA PETROLEUM MACHINERY, 2020,48(3):128-133.
[16] 刘芳,金阿芳,热依汗古丽·木沙.欧拉颗粒流模型下的近床面风沙跃移速度分布特征[J].科学技术与工程,2021,21(6):2157-2163. LIU Fang,JIN Afang,Reyihanguli Musa. Velocity distribution of aeolian saltation on sand bed surface in euler-granular model[J].Science Technology and Engineering,2021,21(6):2157-2163.
[17] 左伟芹,谢坤容,韩红凯,等.清洁压裂液携带作用下支撑剂运移铺置规律研究[J].煤矿安全,2022,53(12):42-47. ZUO Weiqin, XIE Kunrong, HAN Hongkai,et al. Study on proppant migration and placement under sand-carrying action of clean fracturing fluid[J]. Safety in Coal Mines, 2022, 53(12):42-47.
[18] 张涛,郭建春,刘伟.清水压裂中支撑剂输送沉降行为的CFD模拟[J].西南石油大学学报(自然科学版),2014,36(1):74-82. ZHANG Tao,GUO Jianchun,LIU Wei. CFD simulation of proppant transportation and settling in water fracture treatments[J]. Journal of Southwest Petroleum University(Science&Technology Edition),2014,36(1):74-82.
[19] Zhou M M, Kuang S, Luo K, et al. Modeling and analysis of flow regimes in hydraulic conveying of coarse particles[J]. Powder Technology, 2020, 373:543-554.
[20] Ravelet F, Bakir F, Khelladi S, et al. Experimental study of hydraulic transport of large particles in horizontal pipes[J]. Experimental Thermal and Fluid Science, 2013, 45:187-197.
[21] Miedema S A. The heterogeneous to homogeneous transition for slurry flow in pipes[J]. Ocean Engineering, 2016, 123:422-431.
[22] Ramsdell R C, Miedema S A. An overview of flow regimes describing slurry transport[J]. WODCON XX, 2013:15.
[23] Raffi M. Turian,Tran-Fu Yuan. Flow of slurries in pipelines[J]. AIChe Journal, 23(3), 1977, 232-243.
[24] Zandi Iraj. Advances in solid-liquid flow in pipes and its application[M]. Elsevier, 2013:16-21.
[25] 中华人民共和国交通部. 疏浚工程技术规范:JTJ319-99[S]. 北京:中国标准出版社,1999.
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