Citation: | CHEN Siliang, JIANG Zebiao, QUAN Xiping, et al. Study on pore structure and fractal characteristics of fractured coal based on mercury injection and low temperature nitrogen adsorption tests[J]. Safety in Coal Mines, 2024, 55(11): 84−91. DOI: 10.13347/j.cnki.mkaq.20222157 |
In order to study the effect of cracking on the pore microstructure of coal rock, low-temperature nitrogen adsorption meth-od and mercury injection method were used to study the pore morphology and pore size distribution of coal samples before and after cracking, and then the fractal dimension of pores in different ranges was calculated based on the data of low-temperature nitrogen and mercury injection combined with the fractal theory. The results show that the pore volume of coal samples increases after cracking. The large pore volume of cracked coal is 1.4−2.2 times that of raw coal, and the micropore volume is 3.7−8.2 times that of raw coal. The fractal dimension of raw coal’s seepage pore and adsorption pore is greater than that of cracking coal at pressure less than 13.8 MPa and low pressure zone, and the fractal dimension of raw coal’s diffusion pore is smaller than that of cracking coal at pressure more than 13.8 MPa but less than 137.9 MPa and high pressure zone.
[1] |
袁亮. 低透高瓦斯煤层群安全开采关键技术研究[J]. 岩石力学与工程学报,2008,27(7):1370−1379. doi: 10.3321/j.issn:1000-6915.2008.07.009
YUAN Liang. Key technique of safe mining in low permeability and methane-rich seam group[J]. Chinese Journal of Rock Mechanics and Engineering, 2008, 27(7): 1370−1379. doi: 10.3321/j.issn:1000-6915.2008.07.009
|
[2] |
袁亮. 我国深部煤与瓦斯共采战略思考[J]. 煤炭学报,2016,41(1):1−6.
YUAN Liang. Strategic thinking of simultaneous exploitation of coal and gas in deep mining[J]. Journal of China Coal Society, 2016, 41(1): 1−6.
|
[3] |
蓝航,陈东科,毛德兵. 我国煤矿深部开采现状及灾害防治分析[J]. 煤炭科学技术,2016,44(1):39−46.
LAN Hang, CHEN Dongke, MAO Debing. Current status of deep mining and disaster prevention in China[J]. Coal Science and Technology, 2016, 44(1): 39−46.
|
[4] |
虎维岳. 深部煤炭开采地质安全保障技术现状与研究方向[J]. 煤炭科学技术,2013,41(8):1−5.
HU Weiyue. Study orientation and present status of geological guarantee technologies to deep mine coal mining[J]. Coal Science and Technology, 2013, 41(8): 1−5.
|
[5] |
谢和平,周宏伟,薛东杰,等. 我国煤与瓦斯共采:理论、技术与工程[J]. 煤炭学报,2014,39(8):1391−1397.
XIE Heping, ZHOU Hongwei, XUE Dongjie, et al. Theory, technology and engineering of simultaneous exploitation of coal and gas in China[J]. Journal of China Coal Society, 2014, 39(8): 1391−1397.
|
[6] |
刘生龙,朱传杰,林柏泉,等. 水力割缝空间分布模式对煤层卸压增透的作用规律[J]. 采矿与安全工程学报,2020,37(5):983−990.
LIU Shenglong, ZHU Chuanjie, LIN Baiquan, et al. The effect of spatial distribution mode of hydraulic slotting on pressure relief and permeability enhancement of the coal seam[J]. Journal of Mining & Safety Engineering, 2020, 37(5): 983−990.
|
[7] |
袁亮,薛俊华,张农,等. 煤层气抽采和煤与瓦斯共采关键技术现状与展望[J]. 煤炭科学技术,2013,41(9):6−11.
YUAN Liang, XUE Junhua, ZHANG Nong, et al. Development orientation and status of key technology for mine underground coal bed methane drainage as well as coal and gas simultaneous mining[J]. Coal Science and Technology, 2013, 41(9): 6−11.
|
[8] |
吴财芳,曾勇,秦勇. 煤与瓦斯共采技术的研究现状及其应用发展[J]. 中国矿业大学学报,2004,33(2):137−140. doi: 10.3321/j.issn:1000-1964.2004.02.003
WU Caifang, ZENG Yong, QIN Yong. Present situation, application, and development of simultaneous extraction of coal and gas[J]. Journal of China University of Mining & Technology, 2004, 33(2): 137−140. doi: 10.3321/j.issn:1000-1964.2004.02.003
|
[9] |
韩亚北. 液态二氧化碳相变致裂增透机理研究[D]. 焦作:河南理工大学,2014:50−55.
|
[10] |
王兆丰,孙小明,陆庭侃,等. 液态CO2相变致裂强化瓦斯预抽试验研究[J]. 河南理工大学学报(自然科学版),2015,34(1):1−5.
WANG Zhaofeng, SUN Xiaoming, LU Tingkan, et al. Experiment research on strengthening gas drainage effect with fracturing technique by liquid CO2 phase transition[J]. Journal of Henan Polytechnic University (Natural Science), 2015, 34(1): 1−5.
|
[11] |
HU G Z, HE W R, SUN M. Enhancing coal seam gas using liquid CO2 phase-transition blasting with cross-measure borehole[J]. Journal of Natural Gas Science and Engineering, 2018, 60: 164−173. doi: 10.1016/j.jngse.2018.10.013
|
[12] |
WEN H, WEI G M, MA L, et al. Damage characteristics of coal microstructure with liquid CO2 freezing-thawing[J]. Fuel, 2019, 249: 169−177. doi: 10.1016/j.fuel.2019.03.110
|
[13] |
DENG B Z, YIN G Z, ZHANG D M, et al. Experimental investigation of fracture propagation induced by carbon dioxide and water in coal seam reservoirs[J]. Powder Technology, 2018, 338: 847−856. doi: 10.1016/j.powtec.2018.07.071
|
[14] |
李希建,沈仲辉,刘钰,等. 黔西北构造煤与原生结构煤孔隙结构对吸解特性影响实验研究[J]. 采矿与安全工程学报,2017,34(1):170−176.
LI Xijian, SHEN Zhonghui, LIU Yu, et al. The experimental research on the impact of pore structure in tectonic coal and primary structure coal on gas adsorption-desorption characteristics in northwestern Guizhou[J]. Journal of Mining & Safety Engineering, 2017, 34(1): 170−176.
|
[15] |
倪冠华,李钊,温永瓒,等. CO2注入下煤层气产出及储层渗透率演化规律[J]. 采矿与安全工程学报,2022,39(4):837−846.
NI Guanhua, LI Zhao, WEN Yongzan, et al. Evolution of coalbed methane output and reservoir permeability under CO2 injection[J]. Journal of Mining & Safety Engineering, 2022, 39(4): 837−846.
|
[16] |
LIU Y, ZHU Y M, LIU S M, et al. Temperature effect on gas adsorption capacity in different sized pores of coal: Experiment and numerical modeling[J]. Journal of Petroleum Science and Engineering, 2018, 165: 821−830. doi: 10.1016/j.petrol.2018.03.021
|
[17] |
OKOLO G N, EVERSON R C, NEOMAGUS H W J P, et al. Comparing the porosity and surface areas of coal as measured by gas adsorption, mercury intrusion and SAXS techniques[J]. Fuel, 2015, 141: 293−304. doi: 10.1016/j.fuel.2014.10.046
|
[18] |
李阳,张玉贵,张浪,等. 基于压汞、低温N2吸附和CO2吸附的构造煤孔隙结构表征[J]. 煤炭学报,2019,44(4):1188−1196.
LI Yang, ZHANG Yugui, ZHANG Lang, et al. Characterization on pore structure of tectonic coals based on the method of mercury intrusion, carbon dioxide adsorption and nitrogen adsorption[J]. Journal of China Coal Society, 2019, 44(4): 1188−1196.
|
[19] |
陈珍,赵萌. 煤的孔隙特征研究进展与现状[C]//北京力学会第二十八届学术年会论文集(上). 北京:北京力学会,2022:259−261.
|
[20] |
谢启红,邵先杰,时培兵,等. 低温氮吸附法在页岩储层微观孔隙表征中的作用[J]. 河北工程大学学报(自然科学版),2016,33(3):99−103. doi: 10.3969/j.issn.1673-9469.2016.03.021
XIE Qihong, SHAO Xianjie, SHI Peibing, et al. Characterization of low-temperature nitrogen adsorption method in microscopic pore of shale reservoir[J]. Journal of Hebei University of Engineering (Natural Science Edition), 2016, 33(3): 99−103. doi: 10.3969/j.issn.1673-9469.2016.03.021
|
[21] |
LIU X F, NIE B S, GUO K Y, et al. Permeability enhancement and porosity change of coal by liquid carbon dioxide phase change fracturing[J]. Engineering Geology, 2021, 287: 106106. doi: 10.1016/j.enggeo.2021.106106
|
[22] |
彭鑫,江泽标,李波波,等. 二氧化碳致裂对煤岩孔隙表面分形特征影响实验研究[J]. 中国安全生产科学技术,2019,15(2):111−117.
PENG Xin, JIANG Zebiao, LI Bobo, et al. Experimental study on influence of CO2 cracking on surface fractal characteristics of coal pore[J]. Journal of Safety Science and Technology, 2019, 15(2): 111−117.
|
[23] |
郭亚玲,江泽标,彭鑫,等. 二氧化碳致裂对煤孔隙结构影响的试验研究[J]. 煤矿安全,2022,53(7):20−26.
GUO Yaling, JIANG Zebiao, PENG Xin, et al. Experimental study on the influence of carbon dioxide cracking on coal pore structure[J]. Safety in Coal Mines, 2022, 53(7): 20−26.
|
[24] |
陈悦,李东旭. 压汞法测定材料孔结构的误差分析[J]. 硅酸盐通报,2006,25(4):198−201. doi: 10.3969/j.issn.1001-1625.2006.04.044
CHEN Yue, LI Dongxu. Analysis of error for pore structure of porous materials measured by MIP[J]. Bulletin of the Chinese Ceramic Society, 2006, 25(4): 198−201. doi: 10.3969/j.issn.1001-1625.2006.04.044
|
[25] |
LIAO Z W, LIU X F, SONG D Z, et al. Micro-structural damage to coal induced by liquid CO2 phase change fracturing[J]. Natural Resources Research, 2021, 30(2): 1613−1627. doi: 10.1007/s11053-020-09782-5
|
[26] |
SING K S W. Reporting Physisorption Data for Gas/Solid Systems with special reference to the determination of surface area and porosity (Recommendations 1984)[J]. Pure and Applied Chemistry, 1985, 57: 603−619. doi: 10.1351/pac198557040603
|
[27] |
WASHBURN E W. The dynamics of capillary flow[J]. Physical Review, 1921, 17(3): 273−283. doi: 10.1103/PhysRev.17.273
|
[28] |
PFEIFER P, WU Y J, COLE M W, et al. Multilayer adsorption on a fractally rough surface[J]. Phys Rev Lett, 1989, 62(17): 1997−2000. doi: 10.1103/PhysRevLett.62.1997
|
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