液氮注入煤体致裂全过程真三轴试验系统研发与应用

摘要
图/表
参考文献
相关文章 (15)

全文: PDF (5146 KB) HTML (1 KB)
输出: BibTeX | EndNote (RIS)

摘要我国大部分煤层渗透率较低，液氮致裂作为一种无水压裂技术，促使煤层破裂产生裂隙网络，有效改善煤层渗透特性。实际煤层处于三维应力环境，使得煤体损伤破裂特性更为复杂，为进一步研究真三轴应力下液氮致裂煤体裂缝起裂扩展规律，综合考虑煤层真实应力环境和液氮低温特性，自主研发液氮注入致裂煤体真三轴试验系统，主要包括真三轴应力加载、液氮增压注入、回压保压和数据采集等模块。试件尺寸150 mm×150 mm×150 mm，真三轴最大加载应力1 500 kN，最大注入压力20 MPa，压裂系统承压能力大于25 MPa。利用试验系统开展不同水平应力比下液氮注入致裂煤体试验，结果表明：液氮致裂煤体过程压力–时间曲线可分为压力平稳、压力上升和压力急剧下降3个阶段。水平应力比越高，煤体破裂时间越早，破裂压力越低，累积振铃计数逐渐减小。水平应力比由1增加到3时，破裂压力由11.37 MPa降低到5.21 MPa，降幅54.18%。煤样主裂缝沿着最大水平主应力方向扩展，主裂缝产生分支裂缝，裂缝形态从三翼断裂裂缝转化为单一裂缝。试验系统为进一步探讨真三轴应力下液氮致裂煤体裂缝扩展规律，揭示液氮致裂煤体增透机制提供一定试验基础。

	服务

	把本文推荐给朋友
	加入我的书架
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章
	林海飞1
	2
	李博涛3
	李树刚1
	2
	魏宗勇1
	2
	严敏1
	2
	秦雷1
	2
	王裴1
	罗荣卫1
	刘泽然1

关键词 ：采矿工程, 煤层增透, 试验系统研发, 真三轴应力, 液氮致裂, 裂缝扩展

Abstract：Most of the coal seams in China have low permeability. Liquid nitrogen(LN2) fracturing，an anhydrous fracturing technology，induces coal seam rupture and forms a fracture network，significantly enhancing permeability. The actual coal seam is in a three-dimensional stress environment，making the damage and fracture characteristics of the coal more complex. To investigate the fracture initiation and expansion law of LN2 fracturing coal under true triaxial stress，a true triaxial experimental system for LN2 injection fracturing coal has been independently developed by considering the real stress environment of the coal seam and the low-temperature LN2 characteristics. The system mainly includes the true triaxial stress loading，LN2 pressurized injection，pressure holding，and data acquisition modules. The specimen size of the system is 150 mm×150 mm×150 mm，the maximum loading stress of true triaxial is 1 500 kN and the maximum pressure of the injection is 20 MPa，and the pressure-bearing capacity of the hydraulic fracturing system is more than 25 MPa. The test system was utilized to carry out tests on fracturing coal by LN2 injection at different horizontal stress ratios. The results show that the pressure-time curve of the LN2 fracturing coal process can be divided into three stages：stable pressure，rising pressure and sharp pressure drop. An increase in the horizontal stress ratio results in an earlier coal rupture time，a reduction in the rupture pressure and a gradual decrease in the cumulative ringing count. When the horizontal stress ratio increased from 1 to 3，the rupture pressure decreased from 11.37 to 5.21 MPa，with a decrease of 54.18%. The fractures in the coal samples primarily expanded along the direction of the maximum horizontal principal stress，with the main fracture producing branching fractures. The fracture morphology evolved from a three-wing fracture pattern to a single fracture structure. The experimental system provides a certain experimental basis for further exploring the crack expansion law of LN2 fracturing coal and revealing the penetration enhancement mechanism of LN2 fracturing coal.

Key words： mining engineering coal seam permeability enhancement test system development true triaxial stress liquid nitrogen fracturing fracture propagation

引用本文:

林海飞1，2，李博涛3，李树刚1，2，魏宗勇1，2，严敏1，2，秦雷1，2，王裴1，罗荣卫1，刘泽然1. 液氮注入煤体致裂全过程真三轴试验系统研发与应用[J]. 岩石力学与工程学报, 2025, 44(2): 276-291.
LIN Haifei1，2，LI Botao3，LI Shugang1，2，WEI Zongyong1，2，YAN Min1，2，QIN Lei1，2，WANG Pei1，LUO Rongwei1，LIU Zeran1. Development and application of true triaxial experimental system for the whole process of coal fracturing induced by liquid nitrogen injection. , 2025, 44(2): 276-291.

链接本文:

https://rockmech.whrsm.ac.cn/CN/Y2025/V44/I2/276

[1]	袁亮. 煤炭工业碳中和发展战略构想[J]. 中国工程科学，2023，25(5)：103-110.(YUAN Liang. Strategic conception of carbon neutralization in coal industry[J]. Strategic Study of CAE，2023，25(5)：103-110.(in Chinese))
[2]	谢和平，吴立新，郑德志. 2025年中国能源消费及煤炭需求预测[J]. 煤炭学报，2019，44(7)：1 949-1 960.(XlE Heping，WU Lixin，ZHENG Dezhi. Prediction on the energy consumption and coal demand of China in 2025[J]. Journal of China Coal Society，2019，44(7)： 1 949-1 960.(in Chinese))
[3]	卢义玉，廖引，汤积仁，等. 页岩超临界CO2压裂起裂压力与裂缝形态试验研究[J]. 煤炭学报，2018，43(1)：175-180.(LU Yiyu，LIAO Yin，TANG Jiren，et al. Experimental study on fracture initiation pressure and morphology in shale using supercritical CO2 fracturing[J]. Journal of China Coal Society，2018，43(1)：175-180.(in Chinese))
[4]	刘健，刘泽功，高魁，等. 深孔定向聚能爆破增透机制模拟试验研究及现场应用[J]. 岩石力学与工程学报，2014，33(12)：2 490-2 496.(LIU Jian，LIU Zegong，GAO Kui，et al. Experimental study and application of directional focused energy blasting in deep boreholes[J]. Chinese Journal of Rock Mechanics and Engineering，2014，33(12)：2 490-2 496.(in Chinese))
[5]	翟成，李贤忠，李全贵. 煤层脉动水力压裂卸压增透技术研究与应用[J]. 煤炭学报，2011，36(12)：1 996-2 001.(ZHAl Cheng，LI Xianzhong，LI Quangui，et al. Research and application of coal seam pulse hydraulic fracturing technology[J]. Journal of China Coal Society，2011，36(12)：1 996-2 001.(in Chinese))
[6]	黄中伟，武晓光，谢紫霄，等. 液氮射流破岩及压裂研究进展[J]. 中国科学基金，2021，35(6)：952-963.(HUANG Zhongwei，WU Xiaoguang，XIE Zixiao，et al. Theory and research progress of liquid nitrogen fracturing and rock breaking[J]. Bulletin of National Natural Science Foundation of China，2021，35(6)：952-963.(in Chinese))
[7]	田苗苗，张磊，薛俊华，等. 液氮致裂煤体技术研究现状及展望[J]. 煤炭科学技术，2022，50(7)：191-198.(TIAN Miaomiao，ZHANG Lei，XUE Junhua，et al. Study and prospection of liquid nitrogen fracturing coal technology[J]. Coal Science and Technology，2022，50(7)：191-198.(in Chinese))
[8]	MCDANIEL B W，GRUNDMANN S R，KENDRICK W D，et al. Field applications of cryogenic nitrogen as a hydraulic fracturing fluid[J]. Journal of Petroleum Technology，1998，50(3)：38-39.
[9]	GRUNDMANN S R，RODVELT G D，DIALS G A，et al. Cryogenic nitrogen as a hydraulic fracturing fluid in the devonian shale[C]// Proceedings of the SPE Eastern Regional Meeting. Pittsburgh，Pennsylvania：[s. n.]，1998：SPE-51067-MS.
[10]	CHA M，YIN X，KNEAFSEY T，et al. Cryogenic fracturing for reservoir stimulation-Laboratory studies[J]. Journal of Petroleum Science and Engineering，2014，124：436-450.
[11]	李兆霖，王连国，姜崇扬，等. 基于实时CT扫描的岩石真三轴条件下三维破裂演化规律[J]. 煤炭学报，2021，46(3)：937-949.(LI Zhaolin，WANG Lianguo，JIANG Chongyang，et al. Three-dimensional fracture evolution patterns of rocks under true triaxial conditions based on real-time CT scanning[J]. Journal of China Coal Society，2021，46(3)：937-949.(in Chinese))
[12]	鲁俊，尹光志，高恒，等. 真三轴加载条件下含瓦斯煤体复合动力灾害及钻孔卸压试验研究[J]. 煤炭学报，2020，45(5)：1 812-1 823.(LU Jun，YlN Guangzhi，GAO Heng，et al. Experimental study on compound dynamic disaster and drilling pressure relief of gas-bearing coal under true triaxial loading[J]. Journal of China Coal Society，2020，45(5)：1 812-1 823.(in Chinese))
[13]	ALQATAHNI N B，CHA M，YAO B，et al. Experimental investigation of cryogenic fracturing of rock specimens under true triaxial confining stresses[C]// Proceedings of the SPE Europec featured at 78th EAGE Conference and Exhibition. Vienna，Austria：[s. n.]，2016：SPE-180071-MS.
[14]	YANG R，HONG C，LIU W，et al. Non-contaminating cryogenic fluid access to high-temperature resources：Liquid nitrogen fracturing in a lab-scale Enhanced Geothermal System[J]. Renewable Energy，2021，165：125-138.
[15]	洪纯阳，杨睿月，黄中伟，等. 液氮循环压裂裂缝起裂与形态特征可视化研究[J]. 石油科学通报，2023，8(1)：87-101.(HONG Chunyang，YANG Ruiyue，HUANG Zhongwei，et al. Visualization of fracture initiation and morphology by cyclic liquid nitrogen fracturing[J]. Petroleum Science Bulletin，2023，8(1)：87-101.(in Chinese))
[16]	CHA M，ALQAHTANI N B，YAO B，et al. Cryogenic fracturing of wellbores under true triaxial-confining stresses：experimental investigation[J]. Spe Journal，2018，23(4)：1 271-1 289.
[17]	QU H，TANG S，LIU Y，et al. Characteristics of complex fractures by liquid nitrogen fracturing in brittle shales[J]. Rock Mechanics and Rock Engineering，2022，55：1 807-1 822.
[18]	HAN S，CHENG Y，GAO Q，et al. Experimental study of the effect of liquid nitrogen pretreatment on shale fracability[J]. Journal of Natural Gas Science and Engineering，2018，60：11-23.
[19]	秦雷. 液氮循环致裂煤体孔隙结构演化特征及增透机制研究[博士学位论文][D]. 徐州：中国矿业大学，2018.(QIN Lei. Pore evolution after fracturing with cyclic liquid nitrogen and the mechanism of permeability enhancing[Ph. D. Thesis][D]. Xuzhou：China University of Mining and Technology，2018.(in Chinese))
[20]	CHA M，YIN X，KNEAFSEY T，et al. Cryogenic fracturing for reservoir stimulation-Laboratory studies[J]. Journal of Petroleum Science and Engineering，2014，124：436-450.
[21]	何满潮，苗金丽，李德建，等. 深部花岗岩试样岩爆过程试验研究[J]. 岩石力学与工程学报，2007，26(5)：865-876.(HE Manchao，MIAO Jinli，LI Dejian，et al. Experimental study on rockburst process of granite specimen at large depths[J]. Chinese Journal of Rock Mechanics and Engineering，2007，26(5)：865-876.(in Chinese))
[22]	中华人民共和国行业标准编写组. T/CSRME 007―2021 岩石真三轴试验规程[S]. 北京：中国标准出版社，2021.(The Professional Standards Compilation Group of People?s Republic of China. T/CSRME 007―2021 Technical specification for true triaxial test of rock specimen[S]. Beijing：Standards Press of China，2021.(in Chinese))
[23]	中华人民共和国国家标准编写组. GB/T 23561.7—2009 煤和岩石物理力学性质测定方法第7部分：单轴抗压强度测定及软化系数计算方法[S]. 北京：中国标准出版社，2010.(The National Standards Compilation Group of People?s Republic of China. GB/T 23561.7—2009 Methods for determining the physical and mechanical properties of coal and rock—Part 7：Methods for determining the uniaxial compressive strength and counting softening coefficient[S]. Beijing：Standards Press of China，2010.(in Chinese))
[24]	中华人民共和国国家标准编写组. GB/T 212—2008 煤的工业分析方法[S]. 北京：中国标准出版社，2008.(The National Standards Compilation Group of People?s Republic of China. GB/T 212—2008 Proximate analysis of coal[S]. Beijing：Standards Press of China，2008.(in Chinese))
[25]	景锋，盛谦，张勇慧，等. 中国大陆浅层地壳实测地应力分布规律研究[J]. 岩石力学与工程学报，2007，26(10)：2 056-2 062. (JING Feng，SHENG Qian，ZHANG Yonghui，et al. Research on the distribution rule of shallow geostress in China mainland[J]. Chinese Journal of Rock Mechanics and Engineering，2007，26(10)：2 056-2 062.(in Chinese))
[26]	康红普，伊丙鼎，高富强，等. 中国煤矿井下地应力数据库及地应力分布规律[J]. 煤炭学报，2019，44(1)：23-33.(KANG Hongpu，YI bingding，GAO Fuqiang，et al. Database and characteristics of underground in-situ stress distribution in Chinese coal mines[J]. Journal of China Coal Society，2019，44(1)：23-33.(in Chinese))
[27]	柳贡慧，庞飞，陈治喜. 水力压裂模拟试验中的相似准则[J]. 石油大学学报：自然科学版，2000，24(5)：45-48.(LIU Gonghui，PANG Fei，CHEN Zhixi. Development of scaling laws for hydraulic fracturing simulation tests[J]. Journal of China University of Petroleum：Natural Science，2000，24(5)：45-48.(in Chinese))
[28]	CHEN H，HU Y，KANG Y，et al. Fracture initiation and propagation under different perforation orientation angles in supercritical CO2 fracturing[J]. Journal of Petroleum Science and Engineering，2019，183：106403.
[29]	YANG R，WEN H，HUANG Z，et al. Experimental investigation on fracture characteristics by liquid nitrogen compound fracturing in coal[J]. Fuel，2023，340：127434.
[30]	ZHANG X，LU Y，TANG J，et al. Experimental study on fracture initiation and propagation in shale using supercritical carbon dioxide fracturing[J]. Fuel，2017，190：370-378.
[31]	ZHAO X，WANG L，YAO B，et al. Cryogenic fracturing of synthetic coal specimens under true-triaxial loadings-An experimental study[J]. Fuel，2022，324：124530.
[32]	李树刚，马瑞峰，许满贵，等. 地应力差对煤层水力压裂的影响[J]. 煤矿安全，2015，46(3)：140-144.(LI Shugang，MA Ruifeng，XU Mangui，et al. Influence of ground stress deviation on coal seam hydraulic fracturing[J]. Safety in Coal Mines，2015，46(3)：140-144.(in Chinese))
[33]	HONG C，YANG R，HUANG Z，et al. Fracture initiation and morphology of tight sandstone by liquid nitrogen fracturing[J]. Rock Mechanics and Rock Engineering，2022，55(3)：1 285-1 301.
[34]	WEN H，YANG R，LU M，et al. Experimental comparisons of different cryogenic fracturing methods on coals[J]. Journal of Petroleum Science and Engineering，2023，220：111250.
[35]	黄荣樽. 水力压裂裂缝的起裂和扩展[J]. 石油勘探与开发，1981，(5)：62-74.(HUANG Rongzun. Fracture initiation and propagation in hydraulic fracturing[J]. Petroleum Exploration and Development，1981，(5)：65-77.(in Chinese))
[36]	陈江湛，曹函，孙平贺，等. 三轴加载下煤岩脉冲水力压裂扩缝机制研究[J]. 岩土力学，2017，38(4)：1 023-1 031.(CHEN Jiangzhan，CAO Ha，SUN Pinghe，et al. Mechanisms of fracture extending in coal rock by pulse hydraulic fracturing under triaxial loading[J]. Rock and Soil Mechanics，2017，38(4)：1 023-1 031.(in Chinese))
[37]	房柳林. 钻孔轴向预制裂缝岩石水力压裂声发射定位特征试验研究[硕士学位论文][D]. 徐州：中国矿业大学，2022.(FANG Liulin. Experimental Study on mechanism of acoustic emission location of hydraulic fracturing in rock with borehole axial prefabricated cracks[M. S. Thesis][D]. Xuzhou：China University of Mining and Technology，2022.(in Chinese))
[38]	王凯，左晓欢，杜锋，等. 循环载荷作用下煤岩复合结构宏-细观破坏特征及能量-损伤本构研究[J]. 煤炭学报，2024，49(2)：767-784.(WANG Kai，ZUO Xiaohuan，DU Feng，et al. Macro-mesoscopic perspective damage characteristics and energy-damage con-stitutive model of coal-rock composite structures subjected to cyclic loading[J]. Journal of China Coal Society，2024，49(2)：767-784.(in Chinese))
[39]	赵钰. 多场耦合下大尺寸页岩水力裂缝扩展及损伤演化研究[硕士学位论文][D]. 长沙：中南大学，2022.(ZHAO Yu. Research on hydraulic fracture propagation and damage evolution of large-sized shale under multi-field coupling[M. S. Thesis][D]. Changsha：Central South University，2022.(in Chinese))