Study on the influence of fracture roughness and aperture on water seepage of coal
-
摘要: 【目的】 煤层注水是矿井除尘、防治煤与瓦斯突出和冲击地压等灾害的关键技术措施，而裂隙粗糙度、开度等形态特征对煤层注水效果具有显著影响。【方法】 借助砂纸和聚酰亚胺高温胶带制备了含有不同粗糙度和开度裂隙的煤样，利用激光光谱共聚焦显微镜精准计算裂隙粗糙度参数，测试裂隙煤样渗流量。【结果和结论】 结果表明，表面高度偏差Ha、表面最大高度Hz和三维形貌分形维数 Ds 可以作为表征煤剖面粗糙程度的参数。煤体渗流量随Ha、Hz和Ds的升高呈指数降低趋势，随着剖面粗糙度从4.69提高到18.43，裂隙内的渗流量最高下降84.42%。裂隙开度在60~90 μm 时其粗糙度对渗流的阻碍效果达到最高，此后粗糙单元阻碍效果开始减弱，裂隙开度在渗流过程占据主导作用。煤体渗流量随裂隙开度的升高呈指数升高的趋势，裂隙开度由30 μm 提高到 150 μm，裂隙渗流量最高可增大355.88倍。通过对裂隙开度和粗糙度与渗流量关系的深入探究，明确了两者在煤层注水过程中的关键作用机制，强调在煤层注水实践中应充分考虑裂隙形态特征，依据不同的裂隙开度和粗糙度情况合理选择注水方式，以实现煤层注水效果的有效提升。Abstract: [Objective] Coal seam water injection is a key technical measure for dust removal, prevention and control of coal and gas outbursts, and rockburst disasters in mines. The morphological characteristics such as fracture roughness and aperture have a significant impact on the effectiveness of coal seam water injection. [Methods] Fractured coal samples with different roughness and aperture were prepared by means of sandpaper and polyimide high temperature tape. The fracture roughness parameters were accurately calculated by laser spectral confocal microscope, and the seepage flow of fractured coal samples was tested. [Results and Conclusions] The results showed that the surface height deviation (Ha), the maximum surface height (Hz) and the fractal dimension (Ds) of 3D morphology can be used as parameters to characterize the roughness of coal profile. The seepage flow of coal decreases exponentially with the increase of Ha, Hz and Ds. As the roughness of the section increases from 4.69 to 18.43, the seepage flow in the fracture decreases by 84.42%. When the fracture aperture is 60~90 μm, the roughness has the highest blocking effect on the seepage. After that, the blocking effect of the rough element begins to weaken, and the fracture aperture plays a leading role in the seepage process. The seepage flow of coal increases exponentially with the increase of fracture aperture. When the fracture aperture is increased from 30 μm to 150 μm, the seepage flow of fracture can be increased by 355.88 times. This study conducted an in-depth exploration of the relationship between fracture aperture, roughness and seepage flow, clarifying their key mechanisms in the process of coal seam water injection. It emphasizes that in coal seam water injection practice, fracture morphology should be fully considered, and water injection methods should be reasonably selected based on different fracture opening and roughness conditions to effectively improve the effectiveness of coal seam water injection.
-
Keywords:
- coal /
- fracture aperture /
- fracture roughness /
- fracture roughness characterization /
- seepage flow /
- dust removal
-
-
[1] 蒋仲安，王龙飞，张晋京，等. 煤层注水对原煤孔隙及甲烷吸脱附性能的影响[J]. 煤炭学报，2018，43(10)：2780–2788. JIANG Zhong’an，WANG Longfei，ZHANG Jinjing，et al. Influence of coal water injection on pore and methane adsorption/desorption properties of raw coal[J]. Journal of China Coal Society，2018，43(10)：2780–2788.
[2] HE Shengquan，ZHAO Dan，GAO Na，et al. Progress and prospects of mining disaster prevention techniques and equipment[J]. Advances in Geo-Energy Research，2024，13(3)：166–168.
[3] WANG Gang，CHEN Xuechang，WANG Shibin，et al. Influence of fracture connectivity and shape on water seepage of low-rank coal based on CT 3D reconstruction[J]. Journal of Natural Gas Science and Engineering，2022，102：104584.
[4] XU Lianman，LI Yajing，DU Linlin，et al. Study on the effect of SDBS and SDS on deep coal seam water injection[J]. Science of the Total Environment，2023，856：158930.
[5] 王刚，陈昊，陈雪畅，等. 基于CT三维重构煤体变开度裂隙渗流特性研究[J]. 中国矿业大学学报，2024，53(1)：59–67. WANG Gang，CHEN Hao，CHEN Xuechang，et al. Study on seepage characteristics of coal fissures with variable apertures based on CT 3D reconstruction[J]. Journal of China University of Mining & Technology，2024，53(1)：59–67.
[6] 刘长友，刘江伟. 煤岩体裂化的弱结构体应力转移原理及应用[J]. 采矿与安全工程学报，2022，39(2)：359–369. LIU Changyou，LIU Jiangwei. Principle and application of stress transfer of weak structure body in coal-rock mass cracking[J]. Journal of Mining & Safety Engineering，2022，39(2)：359–369. [7] 赵明凯，孔德森. 考虑裂隙面粗糙度和开度分形维数的岩石裂隙渗流特性研究[J]. 岩石力学与工程学报，2022，41(10)：1993–2002. ZHAO Mingkai，KONG Desen. Study on seepage characteristics of rock fractures considering fracture surface roughness and opening fractal dimension[J]. Chinese Journal of Rock Mechanics and Engineering，2022，41(10)：1993–2002.
[8] 熊峰，孙昊，姜清辉，等. 粗糙岩石裂隙低速非线性渗流模型及试验验证[J]. 岩土力学，2018，39(9)：3294–3302. XIONG Feng，SUN Hao，JIANG Qinghui，et al. Theoretical model and experimental verification on non-linear flow at low velocity through rough-walled rock fracture[J]. Rock and Soil Mechanics，2018，39(9)：3294–3302. [9] BARTON N，CHOUBEY V. The shear strength of rock joints in theory and practice[J]. Rock Mechanics，1977，10(1)：1–54.
[10] 王培涛，黄浩，张博，等. 基于3D打印的粗糙结构面模型表征及渗流特性试验研究[J]. 岩土力学，2024，45(3)：725–736. WANG Peitao，HUANG Hao，ZHANG Bo，et al. Characterization of rough fracture model and the seepage characteristics based on 3D printing technology[J]. Rock and Soil Mechanics，2024，45(3)：725–736.
[11] BELEM T，HOMAND-ETIENNE F，SOULEY M. Quantitative parameters for rock joint surface roughness[J]. Rock Mechanics and Rock Engineering，2000，33(4)：217–242.
[12] 熊鹏，董宪姝，叶贵川，等. 粗糙度对贫瘦煤表面润湿性的影响[J]. 煤炭工程，2024，56(3)：197-204. XIONG Peng, DONG Xianshu，YE Guichuan, et，al. Effect of roughness on the wettability of lean coal surfaces[J]. Coal Engineering, 2024，56(3)：197-204.
[13] 冯增朝，赵阳升，文再明. 岩体裂缝面数量三维分形分布规律研究[J]. 岩石力学与工程学报，2005，24(4)：601–609. FENG Zengchao，ZHAO Yangsheng，WEN Zaiming. Study on 3d fractal distribution law of the surface number in rock mass[J]. Chinese Journal of Rock Mechanics and Engineering，2005，24(4)：601–609.
[14] 王洪建，崔炎宗，袁广祥，等. 基于单轴压缩试验的不同风化程度花岗岩分形特征分析[J]. 岩土力学，2023，44(8)：2249–2265. WANG Hongjian，CUI Yanzong，YUAN Guangxiang，et al. Fractal characteristics analysis of granite with different weathering degrees based on uniaxial compression experiment[J]. Rock and Soil Mechanics，2023，44(8)：2249–2265.
[15] 覃源，张鑫，柴军瑞，等. 模拟不同节理粗糙度对单裂隙渗流的影响[J]. 应用力学学报，2020，37(1)：455–462. QIN Yuan，ZHANG Xin，CHAI Junrui，et al. Simulating the influence of different joint roughness on single-fracture seepage[J]. Chinese Journal of Applied Mechanics，2020，37(1)：455–462. [16] 李治豪，陈世江. 不同粗糙度裂隙渗流特性数值模拟研究[J]. 矿业安全与环保，2021，48(4)：6–11. LI Zhihao，CHEN Shijiang. Numerical simulation of seepage characteristics of fractures with different roughness[J]. Mining Safety & Environmental Protection，2021，48(4)：6–11.
[17] 段慕白，李皋，孟英峰，等. 不同节理粗糙度系数的裂隙渗流规律研究[J]. 水资源与水工程学报，2013，24(5)：41–44. DUAN Mubai，LI Gao，MENG Yingfeng，et al. Research on regulation of fracture seepage in different joint roughness coefficients[J]. Journal of Water Resources and Water Engineering，2013，24(5)：41–44.
[18] 甘磊，刘玉，张宗亮，等. 岩体裂隙粗糙度表征及其对裂隙渗流特性的影响[J]. 岩土力学，2023，44(6)：1585–1592. GAN Lei，LIU Yu，ZHANG Zongliang，et al. Roughness characterization of rock fracture and its influence on fracture seepage characteristics[J]. Rock and Soil Mechanics，2023，44(6)：1585–1592.
[19] 卢占国，姚军，王殿生，等. 平行裂缝中立方定律修正及临界速度计算[J]. 实验室研究与探索，2010，29(4)：14–16. LU Zhanguo，YAO Jun，WANG Diansheng，et al. Correction of cubic law and calculation of critical velocity in parallel fractures[J]. Research and Exploration in Laboratory，2010，29(4)：14–16.
[20] 张戈，田园，李英骏. 不同JRC粗糙单裂隙的渗流机理数值模拟研究[J]. 中国科学：物理学 力学 天文学，2019，49(1)：30–39. ZHANG Ge，TIAN Yuan，LI Yingjun. Numerical study on the mechanism of fluid flow through single rough fractures with different JRC[J]. Scientia Sinica (Physica，Mechanica & Astronomica)，2019，49(1)：30–39.
[21] 朱红光，易成，谢和平，等. 基于立方定律的岩体裂隙非线性流动几何模型[J]. 煤炭学报，2016，41(4)：822–828. ZHU Hongguang，YI Cheng，XIE Heping，et al. A new geometric model for non-linear flow in rough-walled fractures based on the cubic law[J]. Journal of China Coal Society，2016，41(4)：822–828. [22] BROWN S R，SCHOLZ C H. Broad bandwidth study of the topography of natural rock surfaces[J]. Journal of Geophysical Research：Solid Earth，1985，90(B14)：12575–12582.
[23] 何志成，李晓昭，黄震，等. 裂隙张开度测量的改进中轴算法及应用研究[J]. 人民长江，2018，49(23)：102–108. HE Zhicheng，LI Xiaozhao，HUANG Zhen，et al. Improved axis algorithm for measurement of fracture aperture and its application[J]. Yangtze River，2018，49(23)：102–108.
[24] LI Zheng，LIU Jie，ZHANG Yan，et al. Experimental study of the visible seepage characteristics and aperture measurement of rock fractures[J]. Arabian Journal of Geosciences，2021，14(17)：1795.
[25] 罗亚飞. 煤储层粗糙裂隙网络量化表征与建模及其渗流机理研究[D]. 重庆：重庆大学，2022. LUO Yafei. Quantitative characterization and modeling of rough fracture network in coal reservoir and its seepage mechanism[D]. Chongqing：Chongqing University，2022. [26] HAKAMI E，LARSSON E. Aperture measurements and flow experiments on a single natural fracture[J]. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts，1996，33(4)：395–404.
[27] 韩磊. 无烟煤储层剩余流体赋存模式及其可动性[D]. 徐州：中国矿业大学，2023. HAN Lei. The occurrence mode and movability of residual fluid in anthracite[D]. Xuzhou：China University of Mining and Technology，2023. [28] KHAN A A，YADAV H L，JAISWAL R K. Experimental method to enhance sensitivity and accuracy of measurements in measuring fracture parameters around the crack tip using compact hololens imaging system[J]. Russian Journal of Nondestructive Testing，2023，59(4)：501–506.
[29] 胡冉，钟翰贤，陈益峰. 变开度岩体裂隙多相渗流实验与有效渗透率模型[J]. 力学学报，2023，55(2)：543–553. HU Ran，ZHONG Hanxian，CHEN Yifeng. Experiments and effective permeability model for multiphase flow in rock fractures with variable apertures[J]. Chinese Journal of Theoretical and Applied Mechanics，2023，55(2)：543–553.
[30] XIONG Feng，JIANG Qinghui，CHEN Mingxi. Numerical investigation on hydraulic properties of artificial-splitting granite fractures during normal and shear deformations[J]. Geofluids，2018，2018：9036028.
[31] 曹栩楼，刘江峰，倪宏阳，等. 基于SEM图像的煤层气渗流裂隙开度影响的模拟研究[J]. 煤矿安全，2020，51(5)：173–176. CAO Xulou，LIU Jiangfeng，NI Hongyang，et al. Simulation study on effect of crack opening degree of coalbed methane seepage based on SEM image[J]. Safety in Coal Mines，2020，51(5)：173–176.
[32] SUN Xiaodong，ZHAO Kaikai，SONG Xuehang. Experimental study on dynamic fracture propagation and evolution during coal seam supercritical CO2 fracturing[J]. Physics of Fluids，2024，36(7)：077172.
[33] 林海飞，李博涛，李树刚，等. 液氮注入煤体致裂全过程真三轴试验系统研发与应用[J/OL]．岩石力学与工程学报. https://link.cnki.net/urlid/42.1397.o3.20241025.1601.005" target="_blank"> https://link.cnki.net/urlid/42.1397.o3.20241025.1601.005 LIN Haifei，LI Botao，LI Shugang，et，al. Development and application of true triaxial experimental system for the whole process of coal fracturing induced by liquid nitrogen injection[J/OL]. Chinese Journal of Rock Mechanics and Engineering. https://link.cnki.net/urlid/42.1397.o3.20241025.1601.005" target="_blank"> https://link.cnki.net/urlid/42.1397.o3.20241025.1601.005.
计量
- 文章访问数: 16
- HTML全文浏览量: 1
- PDF下载量: 1
下载:
