CO2 displacing CH4 under different initial reservoir pressure in triaxial stress
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摘要: 【目的】 为揭示注二氧化碳强化煤层气开采（CO2-ECBM）过程中的储层参数演化规律及初始储层压力对煤层气注气开采效果的影响。【方法】 利用多场耦合煤层注气增产物理模拟试验系统，开展了恒定注气压力2.0 MPa和初始储层压力分别为1.5、1.0和0.5 MPa的注CO2驱替CH4试验研究，探讨了CO2驱替CH4过程中储层压力、温度和体积应变等多物理场参数的时空演化规律及其驱替效果，并在分析其作用机制的基础上对CO2驱替CH4过程进行了阶段划分。【结果和结论】 结果表明：(1)在驱替过程中，注气井储层压力高于生产井储层压力，且压差随初始储层压力增大而增大，最大值为0.34 MPa，而储层平衡压力随初始储层压力增大而减小。(2)储层温度在距离注气井越近的位置越早上升，且初始储层压力越小温度上升速率越大，储层平衡温度随初始储层压力增大而减小。(3)储层体积应变演化可划分为缓慢上升、急速上升、趋于平缓3个阶段，储层体积应变随初始储层压力增大而减小。(4)在驱替过程中，初始储层压力从0.5 MPa依次增至1.0、1.5 MPa时，CH4采收率由91.00%依次降至88.48%、86.81%，随初始储层压力增大呈现减小趋势，与之相反，CO2突破时间和CO2封存效率随初始储层压力增大而增大。驱替过程各阶段作用机制不同，阶段1和阶段2的CH4累积体积、CO2封存体积随着初始储层压力的增加而增加，均占整个驱替过程中CH4累积体积、CO2封存体积的80%以上。研究成果为构建煤层气高效开采协同CO2地质封存一体化技术提供理论依据。Abstract: [Objective] This study aims to reveal the evolution laws of reservoir parameters in the process of Carbon dioxide Enhanced Coalbed Methane (CO2-ECBM) and the effect of different initial reservoir pressure on coalbed methane extraction. [Methods] Using physical simulation test system for multi-field coupled stimulation of coal seam gas injection to conduct constant CO2 displacing CH4 experiments with gas injection pressure of 2.0 MPa and initial reservoir pressures of 1.5, 1.0 and 0.5 MPa. The experiments were conducted to study the spatiotemporal evolution laws of multi-physical field parameters such as reservoir pressure, temperature and volumetric strain and the displacement effect during the CO2 displacing CH4 process. Based on the analysis of the mechanism, the CO2 displacing CH4 process was divided into stages. [Results and Conclusions] Key findings are as follows: (1) During the displacement process, the reservoir pressure of gas injection well is higher than that of production well at the same moment, and the pressure difference increases with the increase of the initial reservoir pressure, with a maximum value of 0.34 MPa, while the reservoir equilibrium pressure decreases with the increase of the initial reservoir pressure; (2) The reservoir temperature where located closer to the gas injection well rises first, and the reservoir temperature rises faster when the initial reservoir pressure is smaller. The reservoir equilibrium temperature decreases with the increase of initial reservoir pressure; (3) The reservoir volumetric strain can be divided into three stages: slow rise, rapid rise and leveling off. The reservoir volumetric strain decreases with the increase of initial reservoir pressure; (4) During the displacement process, when the initial reservoir pressure increases from 0.5 MPa to 1.0 MPa and then to 1.5 MPa, the CH4 recovery efficiency decreases from 91.00% to 88.48% and then to 86.81%, showing a decreasing trend with the increase of the initial reservoir pressure. On the contrary, the CO2 breakthrough time and CO2 storage efficiency increases with the increase of initial reservoir pressure. In each stage of the displacement process, the mechanism of action is different. The CH4 cumulative volume and CO2 storage volume in stage 1 and stage 2 increase with the increase of initial reservoir pressure and both accounted for more than 80% of the whole displacement process. The research results provide theoretical basis for the development of integrated technology for efficient coalbed methane recovery and CO2 geological storage.
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[1] 王国法. 煤矿智能化最新技术进展与问题探讨[J]. 煤炭科学技术，2022，50(1)：1-27. WANG Guofa. New technological progress of coal mine intelligence and its problems[J]. Coal Science and Technology，2022，50(1)：1-27.
[2] 徐凤银，侯伟，熊先钺，等. 中国煤层气产业现状与发展战略[J].石油勘探与开发，2023，50(4)：669-682. XU Fengyin，HOU Wei，XIONG Xianyue，et al. The status and development strategy of coalbed methane industry in China[J]. Petroleum Exploration and Development，2023，50(4)：669-682.
[3] 姚艳斌，孙晓晓，万磊. 煤层CO2地质封存的微观机理研究[J]. 煤田地质与勘探，2023，51(2)：146-157. YAO Yanbin，SUN Xiaoxiao，WAN Lei. Micro-mechanism of geological sequestration of CO2 in coal seam[J]. Coal Geology & Exploration，2023，51(2)：146-157.
[4] 桑树勋，袁亮，刘世奇，等. 碳中和地质技术及其煤炭低碳化应用前瞻[J]. 煤炭学报，2022，47(4)：1430-1451. SANG Shuxun，YUAN Liang，LIU Shiqi，et al. Geological technology for carbon neutrality and its application prospect for low carbon coal exploitation and utilization[J]. Journal of China Coal Society，2022，47(4)：1430-1451.
[5] 肖智勇，王刚，刘杰，等. 热-流-固耦合作用下含水煤层渗透率模型建立及应用研究[J]. 岩石力学与工程学报，2024，43(12)：3044-3057. XIAO Zhiyong，WANG Gang，LIU Jie，et al. A permeability model of water-bearing coal seams under thermo-hydro-mechanical coupling effect and its application[J]. Chinese Journal of Rock Mechanics and Engineering，2024，43(12)：3044-3057.
[6] 刘世奇，皇凡生，杜瑞斌，等. CO2地质封存与利用示范工程进展及典型案例分析[J]. 煤田地质与勘探，2023，51(2)：158-174. LIU Shiqi，HUANG Fansheng，DU Ruibin，et al. Progress and typical case analysis of demonstration projects of the geological sequestration and utilization of CO2[J]. Coal Geology & Exploration，2023，51(2)：158-174.
[7] VAN BERGEN F，KRZYSTOLIK P，VAN WAGENINGEN N，et al. Production of gas from coal seams in the Upper Silesian Coal Basin in Poland in the post-injection period of an ECBM pilot site[J]. International Journal of Coal Geology，2009，77(1/2)：175-187.
[8] 黄中伟，李国富，杨睿月，等. 我国煤层气开发技术现状与发展趋势[J]. 煤炭学报，2022，47(9)：3212-3238. HUANG Zhongwei，LI Guofu，YANG Ruiyue，et al. Review and development trends of coalbed methane exploitation technology in China[J]. Journal of China Coal Society，2022，47(9)：3212-3238.
[9] 桑树勋. 二氧化碳地质存储与煤层气强化开发有效性研究述评[J].煤田地质与勘探，2018，46(5)：1-9. SANG Shuxun. Research review on technical effectiveness of CO2 geological storage and enhanced coalbed methane recovery[J]. Coal Geology & Exploration，2018，46(5)：1-9.
[10] 张松航，唐书恒，张守仁，等. 不同排采程度煤储层注CO2驱煤层气模拟评价[J]. 煤炭学报，2022，47(3)：1275-1285. ZHANG Songhang，TANG Shuheng，ZHANG Shouren，et al. Simulation and evaluation of enhanced coalbed methane recovery by CO2 storage in coal reservoirs with different drainage and production levels[J]. Journal of China Coal Society，2022，47(3)：1275-1285.
[11] TANG Jun，LONG Yonghan，ZHANG Lei，et al. Experimental study of coal rank effect on carbon dioxide injection to enhance CBM recovery[J]. Fuel，2023，354：129393.
[12] 孙泽东，任泫琦. 超临界CO2对烟煤Ⅰ型断裂韧性影响的实验研究[J]. 中国煤炭，2024，50(9)：99-110. SUN Zedong，REN Xuanqi. Experimental study on the effect of supercritical CO2 on bituminous coal type Ⅰ fracture toughness[J]. China Coal，2024，50(9)：99-110.
[13] LIU Shiqi，WANG He，SANG Shuxun，et al. Effects of pore structure changes on the CH4 adsorption capacity of coal during CO2-ECBM[J]. Fuel，2022，330：125529.
[14] 王建美，梁卫国，牛栋，等. 超临界CO2作用下无烟煤结构响应及高压吸附机理[J/OL]. 天然气工业，2024：1-13 [2024-03-20]. http：//kns. cnki. net/KCMS/detail/detail. aspx?filename=TRQG20240314001&dbname=CJFD&dbcode=CJFQ. WANG Jianmei，LIANG Weiguo，NIU Dong，et al. Study on the structural response and adsorption mechanism of anthracite coal with supercritical CO2effects[J/OL]. Natural Gas Industry，2024：1-13 [2024-03-20]. http：//kns. cnki. net/KCMS/detail/detail. aspx?filename=TRQG20240314001&dbname=CJFD&dbcode=CJFQ.
[15] 周西华，韩明旭，白刚，等. CO2注气压力对瓦斯扩散系数影响规律实验研究[J]. 煤田地质与勘探，2021，49(1)：81-86. ZHOU Xihua，HAN Mingxu，BAI Gang，et al. Experimental study on the influence of CO2 injection pressure on gas diffusion coefficient[J]. Coal Geology & Exploration，2021，49(1)：81-86.
[16] 韩光，付志豪，白刚，等. CO2注气压力对CH4驱替特性影响实验研究[J]. 中国安全生产科学技术，2022，18(8)：85-90. HAN Guang，FU Zhihao，BAI Gang，et al. Experimental study on influence of CO2 injection pressure on CH4 displacement characteristics[J]. Journal of Safety Science and Technology，2022，18(8)：85-90.
[17] 姜延航，白刚，周西华，等. 煤层注CO2驱替CH4影响因素试验研究[J]. 中国安全科学学报，2022，32(4)：113-121. JIANG Yanhang，BAI Gang，ZHOU Xihua，et al. Experimental study on influence factors of CH4 displacement by CO2[J]. China Safety Science Journal，2022，32(4)：113-121.
[18] 白刚，姜延航，周西华，等. 不同CO2注入温度置换驱替CH4特性试验研究[J]. 煤炭科学技术，2021，49(5)：167-174. BAI Gang，JIANG Yanhang，ZHOU Xihua，et al. Experimental study on characteristics of replacement and displacement of CH4 at different CO2 injection temperatures[J]. Coal Science and Technology，2021，49(5)：167-174.
[19] BAI Gang，SU Jun，LI Xueming，et al. Step-by-step CO2 injection pressure for enhanced coal seam gas recovery：A laboratory study[J]. Energy，2022，260：125197.
[20] 梁卫国，吴迪，赵阳升. CO2驱替煤层CH4试验研究[J]. 岩石力学与工程学报，2010，29(4)：665-673. LIANG Weiguo，WU Di，ZHAO Yangsheng. Experimental study of coalbeds methane replacement by carbon dioxide[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(4)：665-673.
[21] 桑树勋，牛庆合，曹丽文，等. 深部煤层CO2注入煤岩力学响应特征及机理研究进展[J]. 地球科学，2022，47(5)：1849-1864. SANG Shuxun，NIU Qinghe，CAO Liwen，et al. Mechanical response characteristics and mechanism of coal-rock with CO2 injection in deep coal seam：A review[J]. Earth Science，2022，47(5)：1849-1864.
[22] LIU Zhengdong，CHENG Yuanping，WANG Yongkang，et al. Experimental investigation of CO2 injection into coal seam reservoir at in-situ stress conditions for enhanced coalbed methane recovery[J]. Fuel，2019，236：709-716.
[23] BAI Gang，SU Jun，ZHANG Zunguo，et al. Effect of CO2 injection on CH4 desorption rate in poor permeability coal seams：An experimental study[J]. Energy，2022，238：121674.
[24] 杨天鸿，陈立伟，杨宏民，等. 注二氧化碳促排煤层瓦斯机制转化过程实验研究[J]. 东北大学学报(自然科学版)，2020，41(5)：623-628. YANG Tianhong，CHEN Liwei，YANG Hongmin，et al. Experimental study on the conversion process of promoting gas drainage mechanism by CO2 injection[J]. Journal of Northeastern University(Natural Science)，2020，41(5)：623-628.
[25] LI Zhenbao，WANG Shaorui，WEI Gaoming，et al. The seepage driving mechanism and effect of CO2 displacing CH4 in coal seam under different pressures[J]. Energy，2024，293：130740.
[26] JIA Li，PENG Shoujian，XU Jiang，et al. Experimental investigation on disturbance effect during coalbed methane production[J]. Journal of Petroleum Science and Engineering，2022，208：109591.
[27] ZHANG Chaolin，WANG Enyuan，LI Bobo，et al. Laboratory experiments of CO2-enhanced coalbed methane recovery considering CO2 sequestration in a coal seam[J]. Energy，2023，262：125473.
[28] PAN Zhejun，YE Jianping，ZHOU Fubao，et al. CO2 storage in coal to enhance coalbed methane recovery：A review of field experiments in China[J]. International Geology Review，2018，60(5/6)：754-776.
[29] LI Qixian，XU Jiang，PENG Shoujian，et al. Dynamic evolution of the fluid effect of multiple reservoirs due to CBM coproduction：An experimental investigation[J]. Energy & Fuels，2020，34(9)：10947-10957.
[30] 高彩霞，禹艺娜，李志军，等. 高、低阶煤孔隙结构差异性及其对甲烷吸附特性的影响研究[J]. 中国煤炭，2024，50(5)：113-119. GAO Caixia，YU Yina，LI Zhijun，et al. Research on the difference of pore structure between high and low rank coal and its influence on methane adsorption characteristics[J]. China Coal，2024，50(5)：113-119.
[31] WANG Zhonghui，LI Bobo，REN Chonghong，et al. Energy-driven damage constitutive model of water-bearing coal under triaxial compression[J]. Rock Mechanics and Rock Engineering，2024，57(2)：1309-1328.
[32] JIA Li，PENG Shoujian，XU Jiang，et al. Investigation on gas drainage effect under different borehole layout via 3D monitoring of gas pressure[J]. Journal of Natural Gas Science and Engineering，2022，101：104522.
[33] 范晶晶. 煤层CO2封存影响因素及数值模拟研究[D]. 北京：中国矿业大学(北京)，2018. FAN Jingjing. Research on the influence factors of CO2sequestration in coal seams and numerical simulation of CO2 sequestration process[D]. Beijing：China University of Mining & Technology(Beijing)，2018.
[34] XU Jizhao，QIAN Sheng，XU Hexiang，et al. Numerical analysis of reservoir features and injection modes on carbon exchange capacity during CO2-ECBM processes[J]. Energy & Fuels，2024，38(21)：20485-20503.
[35] 王飞，邢好运，李万春，等. 中低阶煤的孔隙结构演化特征[J]. 西安科技大学学报，2020，40(3)：384-392. WANG Fei，XING Haoyun，LI Wanchun，et al. Evolution characteristics of pore structure in medium and low rank coal[J]. Journal of Xi’an University of Science and Technology，2020，40(3)：384-392.
[36] WANG Zhonghui，LI Bobo，REN Chonghong，et al. A permeability model for coal based on elastic and plastic deformation conditions under the interaction of hydro-mechanical effects[J]. Journal of Petroleum Science and Engineering，2022，212：110209.
[37] SU Erlei，WEI Jiaqi，CHEN Haidong，et al. Effect of CO2 injection on coalbed permeability based on a thermal-hydraulic-mechanical coupling model[J]. Energy & Fuels，2024，38(12)：11078-11092.
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