循环冷冲击作用下煤的渗透性变化规律试验研究
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摘要
为了研究循环冷冲击处理对煤体增透作用的影响,利用SLX-80型高低温处理系统对原煤煤样进行多次循环冷冲击处理,并利用电子天平和三轴瓦斯渗流实验系统分别测定了煤样冷冲击处理前后的质量变化和渗透率增加幅度,对比分析了冷冲击处理前后煤样表面的裂纹分布情况。试验研究结果表明,循环冷冲击处理所产生的热应力超过煤体抗拉强度时会在煤体内部形成新的裂缝,增加原始裂缝的有效宽度,从而提高了煤体内部裂缝连通的有效性,有效改善了煤体渗透性;循环冷冲击处理后煤体渗透率的平均增幅为16%～215%,煤体渗透率增幅大小与处理后的裂纹增加数量及其连通性紧密相关;煤岩材料的非均质性、外部应力载荷及"负损伤"效应的影响使得循环冷冲击处理后的煤体渗透率增幅具有明显的随机性,并呈现出非均匀波动变化特征;循环冷冲击处理所产生的收缩-膨胀效应会引起煤体部分碎块脱落,最终导致煤体质量减小,循环冷处理后煤体的平均质量减幅为0.151%。
To investigate the influence of cyclic cold impact treatments on improvement of coal permeability,the SLX-80 high and low temperature treating system was utilized to conduct the cyclic cold impact treatments on raw coal,then the change of mass variation and permeability increment before and after cyclic cold impact were measured respectively by the electronic balance and the triaxial gas seepage experimental system. At the same time,the distribution of cracks on the surface of coal samples were comparatively analyzed before and after cyclic cold impact treatment. The experimental results indicate that when the thermal stress caused by cyclic cold impact exceeding the tensile strength of coal,several new cracks will be generated in coal body and the effective width of original cracks will increase,which can improve the efficiency of crack connectivity and usefully improve the permeability of coal.The average growth of coal permeability after cyclic cold impact is 16% ～ 215% and the increasing magnitude of coal permeability is closely related to the quantity of the newly generated cracks and their connectivity. The influence of the heterogeneity of coal,the external loads and the"negative damage effect"will lead to the obvious randomness of the growth of coal permeability after cyclic cold impact. And the growth of coal permeability will present a characteristic of inhomogeneous fluctuating. The effect of shrinking and swelling caused by cyclic cold impact will lead to the breaking-off of part of coal fragments,which eventually results in the reduction of coal mass. The average mass reduction of coal after cyclic cold impact was 0.151%.
To investigate the influence of cyclic cold impact treatments on improvement of coal permeability,the SLX-80 high and low temperature treating system was utilized to conduct the cyclic cold impact treatments on raw coal,then the change of mass variation and permeability increment before and after cyclic cold impact were measured respectively by the electronic balance and the triaxial gas seepage experimental system. At the same time,the distribution of cracks on the surface of coal samples were comparatively analyzed before and after cyclic cold impact treatment. The experimental results indicate that when the thermal stress caused by cyclic cold impact exceeding the tensile strength of coal,several new cracks will be generated in coal body and the effective width of original cracks will increase,which can improve the efficiency of crack connectivity and usefully improve the permeability of coal.The average growth of coal permeability after cyclic cold impact is 16% ～ 215% and the increasing magnitude of coal permeability is closely related to the quantity of the newly generated cracks and their connectivity. The influence of the heterogeneity of coal,the external loads and the"negative damage effect"will lead to the obvious randomness of the growth of coal permeability after cyclic cold impact. And the growth of coal permeability will present a characteristic of inhomogeneous fluctuating. The effect of shrinking and swelling caused by cyclic cold impact will lead to the breaking-off of part of coal fragments,which eventually results in the reduction of coal mass. The average mass reduction of coal after cyclic cold impact was 0.151%.
引文
[1]秦勇,袁亮,胡千庭,等.我国煤层气勘探与开发技术现状及发展方向[J].煤炭科学技术,2012,40(10):1-6.(Qin Yong,Yuan Liang,Hu Qianting,et al. Status and development orientation of coal bed methane exploration and development technology in China[J]. Coal Science and Technology,2012,40(10):1-6.(in Chinese))
[2] Kiyama T,Nishimoto S,Fujioka M,et al. Coal swelling strain and permeability change with injecting liquid supercritical CO2and N2at stress-constrained conditions[J]. International Journal of Coal Geology,2011,85(1):56-64.
[3] Wang H C,Fu X H,Jian K,et al. Changes in coal pore structure and permeability during N2injection[J].Journal of Natural Gas Science and Engineering,2015,27(2):1234-1241.
[4] Zhou F D,Hussain F,Cinar Y. Injecting pure N2and CO2to coal for enhanced coalbed methane:Experimental observations and numerical simulation[J].International Journal of Coal Geology,2013,116-117:53-62.
[5] Shi J Q,Durucan S,Fujioka M. A reservoir simulation study of CO2injection and N2flooding at the Ishikari coalfield CO2storage pilot project, Japan[J].International Journal of Greenhouse Gas Control,2008,2(1):47-57.
[6]段品佳,王芝银.煤岩孔隙率与渗透率变化规律试验研究[J].地下空间与工程学报,2013,9(6):1283-1288.(Duan Pinjia,Wang Zhiyin. Experimental research on variations of permeability and porosity for coals[J]. Chinese Journal of Underground Space and Engineering,2013,9(6):1283-1288.(in Chinese))
[7]任韶然,范志坤,张亮,等.液氮对煤岩的冷冲击作用机制及试验研究[J].岩石力学与工程学报,2013,32(增2):3790-3794.(Ren Shaoran, Fan Zhikun, Zhang Liang, et al. Mechanisms and experimental study of thermal-shock effect on coal-rock using liquid nitrogen[J]. Chinese Journal of Rock Mechanics and Engineering,2013,32(Supp.2):3790-3794.(in Chinese))
[8]蔡承政,李根生,黄中伟,等.液氮冻结条件下岩石孔隙结构损伤试验研究[J].岩土力学,2014,35(4):965-971.(Cai Chengzheng,Li Gensheng,Huang Zhongwei,et al. Experimental study of rock porous damage under cryogenic nitrogen freezing[J]. Rock and Soil Mechanics, 2014, 35(4):965-971.(in Chinese))
[9]蔡承政,李根生,黄中伟,等.液氮压裂中液氮对岩石破坏的影响试验[J].中国石油大学学报(自然科学版),2014,38(4):98-103.(Cai Chengzheng,Li Gensheng,Huang Zhongwei,et al. Experimental study on effect of liquid nitrogen on rock failure during cryogenic nitrogen fracturing[J]. Journal of China University of Petroleum,2014,38(4):98-103.(in Chinese))
[10]张春会,王来贵,赵全胜,等.液氮冷却煤变形-破坏-渗透率演化模型及数值分析[J].河北科技大学学报,2015,36(1):90-99.(Zhang Chunhui,Wang Laigui,Zhao Quansheng,et al. Permeability evolution model and numerical analysis of coupled coal deformation,failure and liquid nitrogen cooling[J].Journal of Hebei University of Science and Technology,2015,36(1):90-99.(in Chinese))
[11]张春会,李伟龙,王锡朝,等.液氮溶浸煤致裂的机理研究[J].河北科技大学学报,2015,36(4):425-430.(Zhang Chunhui,Li Weilong,Wang Xichao,et al.Research of fracturing mechanism of coal subjected to liquid nitrogen cooling[J]. Hebei University of Science and Technology, 2015, 36(4):425-430.(in Chinese))
[12]李和万,王来贵,张春会,等.冷加载循环作用下煤样强度特性研究[J].中国安全生产科学技术,2016,12(4):10-14.(Li Hewan,Wang Laigui,Zhang Chunhui,et al. Study on characteristic of coal sample strength under cyclic cold loading[J]. Journal of Safety Science and Technology,2016,12(4):10-14.(in Chinese))
[13]杨昊天,徐进,王璐,等.花岗岩力学特性温度效应的实验研究[J].地下空间与工程学报,2013,9(1):96-101.(Yang Haotian, Xu Jin, Wang Lu, et al.Experimental study on temperature effect of the mechanical properties of granite[J]. Chinese Journal of Underground Space and Engineering,2013,9(1):96-101.(in Chinese))
[14]储小送,屈争辉,郭志军,等.碎粉煤中孔隙特性及对冰冻响应试验研究[J].煤炭科学技术,2015,43(9):117-121.(Chu Xiaosong,Qu Zhenghui,Guo Zhijun,et al. Study on fine coal porosity features and response to seam freezing[J]. Coal Science and Technology,2015,43(9):117-121.(in Chinese))
[15]王登科,魏建平,尹光志.复杂应力路径下含瓦斯煤渗透性变化规律研究[J].岩石力学与工程学报,2012, 31(2):303-309.(Wang Dengke, Wei Jianping,Yin Guangzhi. Investigation on change rule of permeability of coal containing gas under complex stress paths[J]. Chinese Journal of Rock Mechanics and Engineering,2012,31(2):303-309.(in Chinese))
[16] Wang D K,Wei J P,Fu Q C,et al. Seepage law and permeability calculation of coal gas based on Klinkenberg effect[J]. Journal of Central South University,2015,22(5):1973-1978.
[17]彭担任,程普军.煤与岩石的导热性能及热导率研究[J].煤,1999,8(4):13-15.(Peng Danren,Cheng Pujun. Thermal conductivity and thermal conductivity of coal and rock[J]. Coal,1999,8(4):13-15.(in Chinese))
[18]张慧梅,张蒙军,谢祥妙,等.冻融循环条件下红砂岩物理力学特性试验研究[J].太原理工大学学报,2015,46(1):69-74.(Zhang Huimei,Zhang Mengjun,Xie Xiangmiao,et al. The experimental study on the physical and mechanical properties of red sandstone under the action of freeze-thaw cycles[J]. Journal of Taiyuan University of Technology,2015,46(1):69-74.(in Chinese))
[19]路亚妮,李新平,肖家双.单裂隙岩体冻融力学特性试验分析[J].地下空间与工程学报,2014,10(3):593-598,649.(Lu Yani,Li Xinping,Xiao Jiashuang.Experimental analysis on mechanical characteristic of single cracked rock mass under freeze-thaw condition[J]. Chinese Journal of underground Space and Engineering, 2014, 10(3):593-598,649.(in Chinese))
[20]王登科.含瓦斯煤岩本构模型与失稳规律研究[D].重庆:重庆大学,2009.(Wang Dengke. Research on constitutive models and instability rules of gas-saturated coal[D]. Chongqing:Chongqing University,2009.(in Chinese))
[21]杨更社,张全胜,蒲毅彬.冻结温度对岩石细观损伤特性的影响[J].西安科技学院学报,2003,23(2):139-142.(Yang Gengshe, Zhang Quansheng, Pu Yibin. On the microdamage characteristics of rock under the frost and thaw conditions[J]. Journal of Xi’an University of Science and Technology,2003,23(2):139-142.(in Chinese))
[2] Kiyama T,Nishimoto S,Fujioka M,et al. Coal swelling strain and permeability change with injecting liquid supercritical CO2and N2at stress-constrained conditions[J]. International Journal of Coal Geology,2011,85(1):56-64.
[3] Wang H C,Fu X H,Jian K,et al. Changes in coal pore structure and permeability during N2injection[J].Journal of Natural Gas Science and Engineering,2015,27(2):1234-1241.
[4] Zhou F D,Hussain F,Cinar Y. Injecting pure N2and CO2to coal for enhanced coalbed methane:Experimental observations and numerical simulation[J].International Journal of Coal Geology,2013,116-117:53-62.
[5] Shi J Q,Durucan S,Fujioka M. A reservoir simulation study of CO2injection and N2flooding at the Ishikari coalfield CO2storage pilot project, Japan[J].International Journal of Greenhouse Gas Control,2008,2(1):47-57.
[6]段品佳,王芝银.煤岩孔隙率与渗透率变化规律试验研究[J].地下空间与工程学报,2013,9(6):1283-1288.(Duan Pinjia,Wang Zhiyin. Experimental research on variations of permeability and porosity for coals[J]. Chinese Journal of Underground Space and Engineering,2013,9(6):1283-1288.(in Chinese))
[7]任韶然,范志坤,张亮,等.液氮对煤岩的冷冲击作用机制及试验研究[J].岩石力学与工程学报,2013,32(增2):3790-3794.(Ren Shaoran, Fan Zhikun, Zhang Liang, et al. Mechanisms and experimental study of thermal-shock effect on coal-rock using liquid nitrogen[J]. Chinese Journal of Rock Mechanics and Engineering,2013,32(Supp.2):3790-3794.(in Chinese))
[8]蔡承政,李根生,黄中伟,等.液氮冻结条件下岩石孔隙结构损伤试验研究[J].岩土力学,2014,35(4):965-971.(Cai Chengzheng,Li Gensheng,Huang Zhongwei,et al. Experimental study of rock porous damage under cryogenic nitrogen freezing[J]. Rock and Soil Mechanics, 2014, 35(4):965-971.(in Chinese))
[9]蔡承政,李根生,黄中伟,等.液氮压裂中液氮对岩石破坏的影响试验[J].中国石油大学学报(自然科学版),2014,38(4):98-103.(Cai Chengzheng,Li Gensheng,Huang Zhongwei,et al. Experimental study on effect of liquid nitrogen on rock failure during cryogenic nitrogen fracturing[J]. Journal of China University of Petroleum,2014,38(4):98-103.(in Chinese))
[10]张春会,王来贵,赵全胜,等.液氮冷却煤变形-破坏-渗透率演化模型及数值分析[J].河北科技大学学报,2015,36(1):90-99.(Zhang Chunhui,Wang Laigui,Zhao Quansheng,et al. Permeability evolution model and numerical analysis of coupled coal deformation,failure and liquid nitrogen cooling[J].Journal of Hebei University of Science and Technology,2015,36(1):90-99.(in Chinese))
[11]张春会,李伟龙,王锡朝,等.液氮溶浸煤致裂的机理研究[J].河北科技大学学报,2015,36(4):425-430.(Zhang Chunhui,Li Weilong,Wang Xichao,et al.Research of fracturing mechanism of coal subjected to liquid nitrogen cooling[J]. Hebei University of Science and Technology, 2015, 36(4):425-430.(in Chinese))
[12]李和万,王来贵,张春会,等.冷加载循环作用下煤样强度特性研究[J].中国安全生产科学技术,2016,12(4):10-14.(Li Hewan,Wang Laigui,Zhang Chunhui,et al. Study on characteristic of coal sample strength under cyclic cold loading[J]. Journal of Safety Science and Technology,2016,12(4):10-14.(in Chinese))
[13]杨昊天,徐进,王璐,等.花岗岩力学特性温度效应的实验研究[J].地下空间与工程学报,2013,9(1):96-101.(Yang Haotian, Xu Jin, Wang Lu, et al.Experimental study on temperature effect of the mechanical properties of granite[J]. Chinese Journal of Underground Space and Engineering,2013,9(1):96-101.(in Chinese))
[14]储小送,屈争辉,郭志军,等.碎粉煤中孔隙特性及对冰冻响应试验研究[J].煤炭科学技术,2015,43(9):117-121.(Chu Xiaosong,Qu Zhenghui,Guo Zhijun,et al. Study on fine coal porosity features and response to seam freezing[J]. Coal Science and Technology,2015,43(9):117-121.(in Chinese))
[15]王登科,魏建平,尹光志.复杂应力路径下含瓦斯煤渗透性变化规律研究[J].岩石力学与工程学报,2012, 31(2):303-309.(Wang Dengke, Wei Jianping,Yin Guangzhi. Investigation on change rule of permeability of coal containing gas under complex stress paths[J]. Chinese Journal of Rock Mechanics and Engineering,2012,31(2):303-309.(in Chinese))
[16] Wang D K,Wei J P,Fu Q C,et al. Seepage law and permeability calculation of coal gas based on Klinkenberg effect[J]. Journal of Central South University,2015,22(5):1973-1978.
[17]彭担任,程普军.煤与岩石的导热性能及热导率研究[J].煤,1999,8(4):13-15.(Peng Danren,Cheng Pujun. Thermal conductivity and thermal conductivity of coal and rock[J]. Coal,1999,8(4):13-15.(in Chinese))
[18]张慧梅,张蒙军,谢祥妙,等.冻融循环条件下红砂岩物理力学特性试验研究[J].太原理工大学学报,2015,46(1):69-74.(Zhang Huimei,Zhang Mengjun,Xie Xiangmiao,et al. The experimental study on the physical and mechanical properties of red sandstone under the action of freeze-thaw cycles[J]. Journal of Taiyuan University of Technology,2015,46(1):69-74.(in Chinese))
[19]路亚妮,李新平,肖家双.单裂隙岩体冻融力学特性试验分析[J].地下空间与工程学报,2014,10(3):593-598,649.(Lu Yani,Li Xinping,Xiao Jiashuang.Experimental analysis on mechanical characteristic of single cracked rock mass under freeze-thaw condition[J]. Chinese Journal of underground Space and Engineering, 2014, 10(3):593-598,649.(in Chinese))
[20]王登科.含瓦斯煤岩本构模型与失稳规律研究[D].重庆:重庆大学,2009.(Wang Dengke. Research on constitutive models and instability rules of gas-saturated coal[D]. Chongqing:Chongqing University,2009.(in Chinese))
[21]杨更社,张全胜,蒲毅彬.冻结温度对岩石细观损伤特性的影响[J].西安科技学院学报,2003,23(2):139-142.(Yang Gengshe, Zhang Quansheng, Pu Yibin. On the microdamage characteristics of rock under the frost and thaw conditions[J]. Journal of Xi’an University of Science and Technology,2003,23(2):139-142.(in Chinese))
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