深部煤层压裂液渗吸调控煤层气解吸增效机制

  • 姚艳斌 ,
  • 马如英 ,
  • 孙晓晓
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  • 1.中国地质大学(北京)能源学院,深部探测与成像全国重点实验室,北京 100083;
    2.中国地质大学(北京)深时数字地球前沿科学中心,北京 100083
姚艳斌(1978-),男,河北邯郸人,中国地质大学(北京)能源学院教授,主要从事煤与煤层气地质及勘探开发研究与教学工作。地址:北京市海淀区学院路29号,中国地质大学(北京)能源学院,邮政编码:100083。E-mail:yyb@cugb.edu.cn

收稿日期: 2025-06-03

  修回日期: 2025-11-12

  网络出版日期: 2025-11-17

基金资助

国家自然科学基金企业创新发展联合基金重点项目“深部煤层流体作用与煤层气富集产出机理”(U24B2018); 国家自然科学基金杰出青年科学基金项目“煤层气储层地质学”(42125205)

Mechanism of enhanced coalbed methane desorption regulated by fracturing fluid imbibition in deep coal seams

  • YAO Yanbin ,
  • MA Ruying ,
  • SUN Xiaoxiao
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  • 1. State Key Laboratory of Deep Earth Exploration and Imaging, School of Energy Resources, China University of Geosciences (Beijing), Beijing 100083, China;
    2. Frontiers Science Center for Deep-Time Digital Earth, China University of Geosciences (Beijing), Beijing 100083, China

Received date: 2025-06-03

  Revised date: 2025-11-12

  Online published: 2025-11-17

摘要

针对传统低矿化度压裂液侵入深部煤层后易导致离子迁移、润湿性改变与气体解吸效率波动等问题,以鄂尔多斯盆地大宁—吉县区块8#煤为研究对象,通过物理模拟实验揭示矿化度梯度对“离子-煤基质-气/水”三相界面的协同控制机制及其在渗吸-解吸中的关键作用。研究表明:离子浓度升高增强煤层流体疏水性,高价离子效应显著;渗吸与离子扩散路径反向,渗吸平衡先于扩散达成,水-煤反应引发矿物溶解与沉淀双重效应;低矿化度压裂液注入含高矿化度溶液储层时,渗透压差驱动渗吸促进CH4解吸但滤失率高,高矿化度压裂液注入含低矿化度溶液储层时,渗透压差为阻力,抑制滤失但提高返排效率。据此提出深部煤层“高—低矿化度序贯注入”策略:先注高矿化度流体构建稳定裂缝网络,后注低矿化度流体拓展渗吸区并增强CH4解吸-扩散。同时建议采取适度焖井的措施增加渗吸体积,实现储层“保压保能”和渗吸置换等多重积极作用。

本文引用格式

姚艳斌 , 马如英 , 孙晓晓 . 深部煤层压裂液渗吸调控煤层气解吸增效机制[J]. 石油勘探与开发, 0 : 1 -1 . DOI: 10.11698/PED.20250319

Abstract

Low-salinity fracturing fluids tend to induce ion migration, alter wettability, and cause fluctuations in gas desorption efficiency when penetrating deep coal seams. Taking the No. 8 coal from the Daning-Jixian block in the Ordos Basin as a representative example, this study employs physical simulation experiments to reveal the coupled control mechanism of salinity gradient on the ion-coal matrix-gas/water interfacial system and its key role in the imbibition-desorption process. The results show that increasing ionic concentration enhances the hydrophobicity of coal, with multivalent ions exhibiting particularly significant effects. The imbibition and ion diffusion occur in opposite directions, with imbibition equilibrium being achieved earlier than ionic equilibrium. Water-coal interactions induce both mineral dissolution and secondary precipitation. When a low-salinity fracturing fluid is injected into a high-salinity reservoir, the osmotic-pressure difference drives imbibition, promotes CH4 desorption, but results in higher fluid loss. Conversely, injecting high-salinity fracturing fluid into a low-salinity reservoir creates a reverse osmotic gradient that suppresses leak-off while improving flowback efficiency. Based on these findings, a high-low salinity sequential injection strategy is proposed for deep coal seams: high-salinity fluid is first injected to form stable fracture networks, followed by low-salinity fluid to enlarge the imbibition zone and enhance CH4 desorption and diffusion. In addition, moderate well soaking is recommended to increase the imbibition volume, thereby achieving multiple positive effects such as maintaining reservoir pressure, preserving formation energy, and promoting imbibition-driven displacement.

参考文献

[1] 李国永, 姚艳斌, 王辉, 等. 鄂尔多斯盆地神木-佳县区块深部煤层气地质特征及勘探开发潜力[J]. 煤田地质与勘探, 2024, 52(2): 70-80.
LI Guoyong, YAO Yanbin, WANG Hui, et al.Deep coalbed methane resources in the Shenmu-Jiaxian block, Ordos Basin, China: Geological characteristics and potential for exploration and exploitation[J]. Coal Geology & Exploration, 2024, 52(2): 70-80.
[2] 牟朋威, 李珮杰, 姚艳斌, 等. 鄂尔多斯盆地佳县地区深部煤层地应力特征及其对储层物性的控制[J]. 石油与天然气地质, 2024, 45(6): 1640-1652.
MOU Pengwei, LI Peijie, YAO Yanbin, et al.In-situ stress in deep coal seams and its control on reservoir physical properties in the Jiaxian area, Ordos Basin[J]. Oil & Gas Geology, 2024, 45(6): 1640-1652.
[3] 徐凤银, 聂志宏, 孙伟, 等. 鄂尔多斯盆地东缘深部煤层气高效开发理论技术体系[J]. 煤炭学报, 2024, 49(1): 528-544.
XU Fengyin, NIE Zhihong, SUN Wei, et al.Theoretical and technological system for highly efficient development of deep coalbed methane in the eastern edge of Ordos Basin[J]. Journal of China Coal Society, 2024, 49(1): 528-544.
[4] 杨帆, 李斌, 王昆剑, 等. 深部煤层气水平井大规模极限体积压裂技术: 以鄂尔多斯盆地东缘临兴区块为例[J]. 石油勘探与开发, 2024, 51(2): 389-398.
YANG Fan, LI Bin, WANG Kunjian, et al.Extreme massive hydraulic fracturing in deep coalbed methane horizontal wells: A case study of the Linxing Block, eastern Ordos Basin, NW China[J]. Petroleum Exploration and Development, 2024, 51(2): 389-398.
[5] MA R Y, YAO Y B, ZHANG X N, et al.Fluid spontaneous imbibition under the influence of osmotic pressure in deep coalbed methane reservoir in the Ordos Basin, China[J]. SPE Journal, 2024, 29(7): 3766-3776.
[6] YUAN X H, YAO Y B, LIU D M, et al.Spontaneous imbibition in coal: Experimental and model analysis[J]. Journal of Natural Gas Science and Engineering, 2019, 67: 108-121.
[7] CHANG Y H, YAO Y B, LIU D M, et al.Behavior and mechanism of water imbibition and its influence on gas permeability during hydro-fracturing of a coalbed methane reservoir[J]. Journal of Petroleum Science and Engineering, 2022, 208(Part E): 109745.
[8] SUN X X, YAO Y B, LIU D M, et al.Investigations of CO2-water wettability of coal: NMR relaxation method[J]. International Journal of Coal Geology, 2018, 188: 38-50.
[9] MA R Y, YAO Y B, FENG D, et al.Ion migration effects during hydro-fracturing of deep high salinity coal seam[J]. Physics of Fluids, 2024, 36(5): 052112.
[10] WANG K, JIANG B B, YE K R, et al.Spontaneous imbibition model for micro-nano-scale pores in shale gas reservoirs considering gas-water interaction[J]. Journal of Petroleum Science and Engineering, 2022, 209: 109893.
[11] UZUN O, KAZEMI H.Assessment of enhanced oil recovery by osmotic pressure in unconventional reservoirs: Application to Niobrara chalk and Codell sandstone[J]. Fuel, 2021, 306: 121270.
[12] 姚艳斌, 刘大锰. 基于核磁共振弛豫谱的煤储层岩石物理与流体表征[J]. 煤炭科学技术, 2016, 44(6): 14-22.
YAO Yanbin, LIU Dameng.Petrophysics and fluid properties characterizations of coalbed methane reservoir by using NMR relaxation time analysis[J]. Coal Science and Technology, 2016, 44(6): 14-22.
[13] YAO Y B, LIU D M, XIE S B.Quantitative characterization of methane adsorption on coal using a low-field NMR relaxation method[J]. International Journal of Coal Geology, 2014, 131: 32-40.
[14] SANAEI A, TAVASSOLI S, SEPEHRNOORI K.Investigation of modified water chemistry for improved oil recovery: Application of DLVO theory and surface complexation model[J]. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2019, 574: 131-145.
[15] MA R Y, YAO Y B, FENG D, et al.Effects of inorganic salt ions on the wettability of deep coal seams: Insights from experiments and molecular simulations[J]. Applied Surface Science, 2024, 672: 160832.
[16] YAO Y B, WANG F, LIU D M, et al.Quantitative characterization of the evolution of in-situ adsorption/free gas in deep coal seams: Insights from NMR fluid detection and geological time simulations[J]. International Journal of Coal Geology, 2024, 285: 104474.
[17] MA R Y, YAO Y B, SUN X X, et al.Effect of reinjected flowback water into deep coal seams on coalbed methane production: Low-field nuclear magnetic resonance and molecular dynamics studies on methane desorption and diffusion[J]. SPE Journal, 2025, 30(6): 3493-3506.
[18] YANG Q, SUN P Z, FUMAGALLI L, et al.Capillary condensation under atomic-scale confinement[J]. Nature, 2020, 588(7837): 250-253.
[19] BENILOV E S.Capillary condensation of saturated vapor in a corner formed by two intersecting walls[J]. Physics of Fluids, 2022, 34(6): 062103.
[20] 唐书恒, 郗兆栋, 张松航, 等. 深部煤层气赋存相态与含气性演化[J]. 煤炭科学技术, 2025, 53(3): 91-100.
TANG Shuheng, XI Zhaodong, ZHANG Songhang, et al.Occurrence phase and gas-bearing evolution of deep coalbed methane[J]. Coal Science and Technology, 2025, 53(3): 91-100.
[21] 牛小兵, 范立勇, 闫小雄, 等. 鄂尔多斯盆地煤岩气富集条件及资源潜力[J]. 石油勘探与开发, 2024, 51(5): 972-985.
NIU Xiaobing, FAN Liyong, YAN Xiaoxiong, et al.Enrichment conditions and resource potential of coal-rock gas in Ordos Basin, NW China[J]. Petroleum Exploration and Development, 2024, 51(5): 972-985.
[22] HE X D, LI P Y, NING J, et al.Geochemical processes during hydraulic fracturing in a tight sandstone reservoir revealed by field and laboratory experiments[J]. Journal of Hydrology, 2022, 612(Part C): 128292.
[23] JI Y K, HENNISSEN J A I, HOUGH E, et al. Geochemical element mobilisation by interaction of Bowland shale with acidic fluids[J]. Fuel, 2021, 289: 119914.
[24] KHAN H J, SPIELMAN-SUN E, JEW A D, et al.A critical review of the physicochemical impacts of water chemistry on shale in hydraulic fracturing systems[J]. Environmental Science & Technology, 2021, 55(3): 1377-1394.
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