二氧化碳爆破致裂激发干热岩储层作用效果

窦斌; 肖鹏; 郑君; 田红; 崔国栋; 吴天予

doi:10.19509/j.cnki.dzkq.2022.0194

二氧化碳爆破致裂激发干热岩储层作用效果

doi: 10.19509/j.cnki.dzkq.2022.0194

中国地质大学(武汉)工程学院, 武汉 430074

基金项目:

国家重点研发计划 2019YFB1504201

自然资源部深部地热资源重点实验室开放基金 KLDGR2022K01

详细信息

作者简介:
窦斌(1973—)，男，教授，博士生导师，主要从事地热能开发利用的研究及教学工作。E-mail：doubin@cug.edu.cn

通讯作者:
郑君(1987—)，女，副教授，主要从事地热能开发利用以及钻进自动化方面的研究及教学工作。E-mail：junzheng@cug.edu.cn

中图分类号: P314
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出版历程
- 收稿日期: 2022-02-25
- 网络出版日期: 2022-11-10

Effect of stimulation in hot dry rock reservoirs from carbon dioxide blasting-induced cracking

Faculty of Engineering, China University of Geosciences(Wuhan), Wuhan 430074

摘要

摘要:
采用二氧化碳爆破致裂为激发干热岩储层提供了一种新的技术思路和途径。为了探究二氧化碳爆破致裂激发干热岩储层的作用效果, 开展了二氧化碳爆破致裂干热岩储层作用范围的数值模拟研究。考虑实际开采过程中钻井液对井壁附近干热岩储层的降温影响, 采用以温差为变量的拟合函数设置损伤区储层材料参数, 用洗井后井壁附近储层温度分布函数设置损伤区储层温度场, 并借助炸药爆破的相关理论、公式设置爆破荷载, 结合COMSOL软件模拟了二氧化碳爆破致裂激发干热岩储层的过程。结果表明, 二氧化碳爆破致裂干热岩过程中存在多次应力集中作用, 且在炮孔附近压应力集中造成压碎区, 压碎区外拉应力作用形成裂隙区; 储层的初始温度以及定压片厚度都会影响二氧化碳爆破致裂激发干热岩储层的作用效果, 其中初始温度对爆破压碎区范围影响较大, 对裂隙区范围影响较小, 定压片厚度改变对压碎区范围影响较小, 主要影响爆破裂隙区的分布。本研究成果可为干热岩地热能后续的开采利用提供理论支持和参考。
- 干热岩 /
- 储层激发 /
- 二氧化碳爆破 /
- 地热能 /
- 数值模拟
Abstract:
Carbon dioxide blasting provides a new technical idea and way to stimulate hot dry rock reservoirs. To explore the effect of carbon dioxide blasting-induced cracking on dry-hot rock reservoirs, a numerical simulation for the action range of carbon dioxide blasting-induced cracking of hot dry rock was carried out. Considering the cooling effect of drilling fluid on the hot dry rock reservoir near the wellbore in the actual mining process, the fitting functions with temperature difference as a variable were adopted to set the material parameters of the reservoir in the damaged area, and the temperature distribution functions of the reservoir near the wellbore after well washing were adopted to set the temperature field of the reservoir in the damaged area. The blasting load was set by the relevant theories and formulas of explosive blasting. Combined with COMSOL software, the process of carbon dioxide blasting to stimulate hot dry rock reservoirs was simulated. The results showed that there were multiple stress concentrations in the process of the dry hot rock cracking caused by carbon dioxide blasting, the compressive stress concentration near the blast hole produced the crushing zone, and the tensile stress outside the crushing zone formed the fracture zone. In addition, the initial temperature of the reservoir and the thickness of the pressure plate would affect the effect of carbon dioxide blasting fracturing to stimulate dry and hot rock reservoirs. The initial temperature had a great influence on the scope of the blasting crushing zone and had little influence on the scope of the fracture zone. The thickness of the pressure plate had little influence on the scope of the crushing zone, which mainly affected the distribution of the blasting fracture zone. The research results could provide a theoretical support and a reference for the subsequent exploitation and utilization of dry-hot rock geothermal energy.
- hot dry rock /
- reservoir stimulation /
- carbon dioxide blasting /
- geothermal energy /
- numerical model

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图 1 典型爆破应力时程曲线示意图

σ_max为峰值应力；t_r为应力上升时间；t_压为压应力作用时间；t_拉为拉应力作用时间

Figure 1. Diagram of the typical blasting stress time history curve

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图 2 储层激发物理模型示意图

Figure 2. Physical model diagram of reservoir stimulation

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图 3 不同初始温度下储层模型温度场分布图

Figure 3. Distribution of the reservoir model temperature field under different initial temperatures

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图 4 储层激发模型网格剖分图

Figure 4. Meshing diagram of the reservoir stimulation model

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图 5 不同时刻最大主应力云图(300℃)

Figure 5. Maximum principal stress nephograms at different times(300℃)

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图 6 不同时刻应力张量云图(300℃)

Figure 6. Stress tensor nephograms at different time(300℃)

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图 7 不同时刻Von-Mises有效应力云图(300℃)

Figure 7. Von-Mises effective stress nephogram at different time(300℃)

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图 8 各监测点Von-Mises有效应力时程曲线图(300℃)

Figure 8. Time history chart of Von-Mises effective stress at each monitoring point(300℃)

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图 9 不同温度储层激发范围示意图

Figure 9. Schematic diagram of the reservoir excitation range at different temperatures

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表 1 不同型号致裂器爆破参数

Table 1. Blasting parameters of different types of crackers

致裂器型号	致裂器外径/mm	定压片厚度/mm	等效装药密度/(kg·m^-3)	峰值荷载P/MPa(n=8~11)
38型	38	3.5	102.040 8	0.73~1.00
		4.0	117.346 9	0.83~1.14
		4.5	132.653 1	0.95~1.30
57型	57	4.0	117.476 4	9.56~13.15
		4.5	132.704 9	10.80~14.85
		5.0	147.933 3	12.04~16.56
95型	95	4.5	132.649 6	231.40~318.16
		5.0	148.034 2	258.23~355.07
		5.5	163.760 7	285.67~392.80

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表 2 不同温度储层应力衰减系数(α)取值

Table 2. Values of the stress attenuation coefficients(α) of reservoir with different temperatures

储层温度	室温(20℃)	300℃	400℃	500℃	600℃
α	2.047	1.960	1.923	1.893	1.825

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表 3 未损伤区储层参数

Table 3. Reservoir parameters in damaged area

参数名称	密度ρ₀/(g·cm^-3)	弹性模量E₀/GPa	泊松比μ₀	抗拉强度RTS₀/MPa	抗压强度UCS₀/MPa
取值	2.614	13.22	0.188	12.02	123.44

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表 4 损伤区储层参数

Table 4. Reservoir parameters in damaged area

参数名称	拟合方程
密度/(g·cm^-3)	ρ₁=2 600-2 600[ρ_%(ΔT)%] ρ_%(ΔT)=0.006 706-0.001 51ΔT+7.748 04×10^-6ΔT²
弹性模量/GPa	E₁(ΔT)=2.773 04×10^-5ΔT²-0.029 8ΔT+13.223 08
泊松比	μ₁(ΔT)=0.188 15+4.333 26×10^-5ΔT+2.734 58×10^-7ΔT²
抗拉强度/MPa	RTS₁(ΔT)=12.019 47-0.015 32ΔT-1.989 64×10^-7ΔT²
抗压强度/MPa	UCS₁(ΔT)=-9.589 93×10^-5ΔT²-0.086 61ΔT+123.439 94

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表 5 不同工况下致裂器参数

Table 5. Parameters of crackers under different working conditions

组别	致裂器型号	定压片厚度/mm	爆破当量/TNT	压力增大系数(n)
工况1	95	5.5	0.479	8
工况2	95	5.0	0.433	11
工况3	95	5.0	0.433	8
工况4	95	4.5	0.388	11
工况5	95	4.5	0.388	8
工况6	57	5.0	0.204	11

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表 6 不同工况致裂器爆破激发范围

Table 6. Blasting excitation range of crackers under different working conditions

组别	压碎区长度模拟值/m	裂隙区长度模拟值/m	压碎区长度解析值/m	裂隙区长度解析值/m
工况1	0.1~0.12	0.88~0.98	0.133 1	0.853 7
工况2	0.12~0.14	0.98~1.08	0.140 4	0.900 5
工况3	0.1~0.12	0.88~0.98	0.129 7	0.831 9
工况4	0.1~0.12	0.88~0.98	0.136 6	0.876 1
工况5	0.08~0.1	0.68~0.78	0.126 2	0.809 4
工况6	＜0.02	＜0.02	0.066 0	0.423 3

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参考文献(27)

[1]	周总瑛, 刘世良, 刘金侠. 中国地热资源特点与发展对策[J]. 自然资源学报, 2015, 30(7): 1210-1221. Zhou Z Y, Liu S L, Liu J X. Study on the characteristics and development strategies of geothermal resources in China[J]. Journal of Natural Resources, 2015, 30(7): 1210-1221(in Chinese with English abstract).
[2]	Hammons T J, Gunnarsson A. Geothermal sustainability in Europe and worldwide[C]//2008 43rd International Universities Power Engineering Conference. IEEE, 2008.
[3]	李德威, 王焰新. 干热岩地热能研究与开发的若干重大问题[J]. 地球科学: 中国地质大学学报, 2015, 40(11): 1858-1869. Li D W, Wang Y X. Major issues of research and development of hot dry rock geothermal energy[J]. Earth Science: Journal of China University of Geosciences, 2015, 40(11): 1858-1869(in Chinese with English abstract).
[4]	Duchane D V. Geothermal energy from hot dry rock: A renew able energy technology moving towards practical implementation[J]. Renewable Energy, 1996, 9(1/4): 1246-1249.
[5]	汪集旸, 胡圣标, 庞忠和, 等. 中国大陆干热岩地热资源潜力评估[J]. 科技导报, 2012, 30(32): 25-31. doi: 10.3981/j.issn.1000-7857.2012.32.002 Wang J Y, Hu S B, Pang Z H, et al. Estimate of geothermal resources potential for hot dry rock in the continental area of China[J]. Science and Technology Review, 2012, 30(32): 25-31(in Chinese with English abstract). doi: 10.3981/j.issn.1000-7857.2012.32.002
[6]	Feng Y, Chen X, Xu X F. Current status and potentials of enhanced geothermal system in China: A review[J]. Renewable and Sustainable Energy Reviews, 2014, 33: 214-223. doi: 10.1016/j.rser.2014.01.074
[7]	Huang W, Cao W, Jiang F. A novel single-well geothermal system for hot dry rock geothermal energy exploitation[J]. Energy, 2018, 162: 630-644. doi: 10.1016/j.energy.2018.08.055
[8]	窦斌, 高辉, 周刚, 等. 我国发展增强型地热开采技术所面临的机遇与挑战[J]. 地质科技情报, 2014, 33(5): 208-210. https://www.cnki.com.cn/Article/CJFDTOTAL-DZKQ201405032.htm Dou B, Gao H, Zhou G, et al. Opportunities and challenges of developing enhance geothermal system technology in China[J]. Geological Science and Technology Information, 2014, 33(5): 208-210(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-DZKQ201405032.htm
[9]	马峰, 蔺文静, 郎旭娟, 等. 我国干热岩资源潜力区深部热结构[J]. 地质科技情报, 2015, 34(6): 176-181. Ma F, Lin W J, Lang X J, at al. Deep geothermal structures of potential hot dry rock resources area in China[J]. Geological Science and Technology Information, 2015, 34(6): 176-181(in Chinese with English abstract).
[10]	陆川, 王贵玲. 干热岩研究现状与展望[J]. 科技导报, 2015, 33(19): 13-21. Lu C, Wang G L. Current status and prospect of hot dry rock research[J]. Science and Technology Review, 2015, 33(19): 13-21(in Chinese with English abstract).
[11]	Cheng Y, Zhang Y, Yu Z, et al. Investigation on reservoir stimulation characteristics in hot dry rock geothermal formations of China during hydraulic fracturing[J]. Rock Mechanics and Rock Engineering, 2021, 54(8): 3817-3845. doi: 10.1007/s00603-021-02506-y
[12]	Zhang W, Wang C, Guo T, et al. Study on the cracking mechanism of hydraulic and supercritical CO₂ fracturing in hot dry rock under thermal stress[J]. Energy, 2021, 221: 119886. doi: 10.1016/j.energy.2021.119886
[13]	徐超, 窦斌, 田红, 等. 二氧化碳爆破致裂建造增强型地热系统热储层工艺探讨[J]. 地质科技情报, 2019, 38(5): 247-252. https://www.cnki.com.cn/Article/CJFDTOTAL-DZKQ201905027.htm Xu C, Dou B, Tian H, et al. Process of carbon dioxide blasting to build EGS thermal reservoir[J]. Geological Science and Technology Information, 2019, 38(5): 247-252(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-DZKQ201905027.htm
[14]	Singh S P. Non-explosive applications of the PCF concept for underground excavation[J]. Tunnelling and Underground Space Technology, 1998, 13(3): 305-311.
[15]	Vidanovic N, Ognjanovic S, Ilincic N, et al. Application of unconventional methods of underground premises construction in coal mines[J]. Technics Technologies Education Management-Ttem, 2011, 6(4): 861-865.
[16]	Caldwell T. A comparison of non-explosive rock breaking techniques[C]//Proceedings of the 12th Australian Tunnelling Conference. [S. l. ]: [s. n. ], 2005.
[17]	董庆祥, 王兆丰, 韩亚北, 等. 液态CO₂相变致裂的TNT当量研究[J]. 中国安全科学学报, 2014, 24(11): 84-88. Dong Q X, Wang Z F, Han Y B, at al. Research on TNT equivalent of liquid CO₂ phase-transition fracturing[J]. China Safety Science Journal, 2014, 24(11): 84-88(in Chinese with English abstract).
[18]	孙小明. 液态二氧化碳相变致裂穿层钻孔强化预抽瓦斯效果研究[D]. 河南焦作: 河南理工大学, 2014. Sun X M. Research on strengthening gas pre-drainage effect with the fracturing technique by liquid CO₂ phase transition in layer through boring[D]. Jiaozuo Henan: Henan Polytechnic University, 2014(in Chinese with English abstract).
[19]	秦江涛, 陈玉涛, 黄文祥. 高压水力压裂和二氧化碳相变致裂联合增透技术[J]. 煤炭科学技术, 2017, 45(7): 80-84. Qin J T, Chen Y T, Huang W X. Combined permeability improved technology with high pressure hydraulic fracturing and carbon dioxide phase change cracking[J]. Coal Science and Technology, 2017, 45(7): 80-84(in Chinese with English abstract).
[20]	成诗冰, 洪志先. 液态CO₂致裂技术在管廊基坑台阶开挖中的应用[J]. 工程爆破, 2021, 27(5): 80-89. https://www.cnki.com.cn/Article/CJFDTOTAL-GCBP202105013.htm Cheng S B, Hong Z X. Application of liquid CO₂ fracturing technology in bench excavation of utility tunnel foundation pit[J]. Engineering Blasting, 2021, 27(5): 80-89(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-GCBP202105013.htm
[21]	周盛涛, 罗学东, 蒋楠, 等. 二氧化碳相变致裂技术研究进展与展望[J]. 工程科学学报, 2021, 43(7): 883-893. https://www.cnki.com.cn/Article/CJFDTOTAL-BJKD202107002.htm Zhou S T, Luo X D, Jiang N, et al. A review on fracturing technique with carbon dioxide phase transition[J]. Chinese Journal of Engineering, 2021, 43(7): 883-893(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-BJKD202107002.htm
[22]	张晋红. 柱状药包在岩石中爆炸应力波衰减规律的研究[D]. 太原: 中北大学, 2005. Zhang J H. Study on the attenuation law of explosion stress wave in rock of cylinder charge[D]. Taiyuan: North University of China, 2005(in Chinese with English abstract).
[23]	东兆星, 邵鹏. 爆破工程[M]. 北京: 中国建筑工业出版社, 2004. Dong Z X, Shao P. Blasting engineering[M]. Beijing: China Architecture and Building Press, 2004(in Chinese).
[24]	戴俊. 柱状装药爆破的岩石压碎圈与裂隙圈计算[J]. 辽宁工程技术大学学报: 自然科学版, 2001(2): 144-147. https://www.cnki.com.cn/Article/CJFDTOTAL-FXKY200102004.htm Dai J. Calculation of rock crushing circle and fissure circle in cylindrical charge blasting[J]. Journal of Liaoning Technical University: Natural Science Edition, 2001(2): 144-147(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-FXKY200102004.htm
[25]	史晓鹏, 张银平, 袁本胜. 爆炸荷载作用下应力波衰减规律研究[J]. 矿冶, 2010, 19(3): 15-17. https://www.cnki.com.cn/Article/CJFDTOTAL-KYZZ201003005.htm Shi X P, Zhang Y P, Yuan B S. Research on weaken rules of stress wave by explosion loads[J]. Mining and Metallurgy, 2010, 19(3): 15-17(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-KYZZ201003005.htm
[26]	朱振南, 田红, 董楠楠, 等. 高温花岗岩遇水冷却后物理力学特性试验研究[J]. 岩土力学, 2018, 39(增刊2): 169-176. https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX2018S2025.htm Zhu Z N, Tian H, Dong N N, et al. Experimental study of physico-mechanical properties of heat-treated granite by water cooling[J]. Rock and Soil Mechanics, 2018, 39(S2): 169-176(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX2018S2025.htm
[27]	夏杰勤, 窦斌, 徐超, 等. 干热岩热储建造的二氧化碳爆破致裂器优化设计[J]. 钻探工程, 2021, 48(1): 75-80. https://www.cnki.com.cn/Article/CJFDTOTAL-TKGC202101011.htm Xia J Q, Dou B, Xu C, et al. Optimum design of CO₂ fracture initiator for thermal reservoir construction in hot dry rock[J]. Drilling Engineering, 2021, 48(1): 75-80(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-TKGC202101011.htm