Tensile behavior and damage mechanisms of hot dry rock under thermal shock fatigue and seawater dissolution

Abstract

Significant potential exists for mining hot dry rock in coastal areas, oceans, islands, and reefs by utilizing abundant seawater as a heat-exchanging medium. It is crucial for optimizing reservoir stimulation technology to explore mechanical characteristics and mechanisms for damage of reservoir rocks during seawater mining of hot dry rock. In this research,granite was subjected to several heat treatment temperatures (100 to 500 °C) and various numbers of fatigue thermal shocks (0-20) using seawater before Brazilian splitting tests and acoustic emission testing. The findings show that temperature, the thermal shocks, and seawater dissolution are the main factors influencing granite’s tensile strength.The temperature threshold for significant degradation of tensile strength, resulting from thermal shock from seawater and heat treatment, ranges from 200 to 300 °C. At high temperatures (300 to 500 °C), seawater decreases the tensile strength of granite by approximately 1.67 times compared to freshwater in cycles 0-10, and by about 3.20 times in cycles 10-20. In general, the higher the temperature and frequency of seawater impact, the greater the plasticity of the rock, the lower the tensile strength, and the higher the cumulative count and energy of acoustic emission. The number of seawater thermal shocks and granite’s tensile strength have a negative link that is substantially amplified by the temperature. The double effects of seawater cold cycle and heat treatment temperature cause granite to become more porous and progressively shift from tensile to shear damage. These results provide a benchmark for utilizing seawater as a thermogenic medium in enhanced geothermal systems for mineral extraction procedures.

Document Type: Original article

Cited as: Li, C., Tu, J., Xie, H., Hu, J. Tensile behavior and damage mechanisms of hot dry rock under thermal shock fatigue and seawater dissolution. Advances in Geo-Energy Research, 2024, 13(2): 132-145. https://doi.org/10.46690/ager.2024.08.07

References

Asai, P., Panja, P., McLennan, J., et al. Efficient workflow for simulation of multifractured enhanced geothermal systems (EGS). Renewable Energy, 2019, 131: 763-777.

Bertani, R. Geothermal power generation in the world 2010-2014 update report. Geothermics, 2016, 60: 31-43.

Breede, K., Dzebisashvili, K., Liu, X., et al. A systematic review of enhanced (or engineered) geothermal systems: Past, present and future. Geothermal Energy, 2013, 1: 4.

Chen, C., Chu, P., Xie, H., et al. Fracture behavior of hightemperature granite subjected to liquid nitrogen cooling: Semi-circular bending test and crack evolution analysis. Theoretical and Applied Fracture Mechanics, 2023, 128: 104100.

Chen, Y., Wang, S., Ni, J., et al. An experimental study of the mechanical properties of granite after high temperature exposure based on mineral characteristics. Engineering Geology, 2017, 220: 234-242.

Deng, H., Hu, J., Liu, G., et al. Study on the surface morphology and fractal characteristics of granite under thermal shock of seawater. Thermal Science, 2023, 27: 571-579.

Ding, Q., Ju, F., Mao, X., et al. Experimental investigation of the mechanical behavior in unloading conditions of sandstone after high-temperature treatment. Rock Mechanics and Rock Engineering, 2016, 49: 2641-2653.

Filipussi, D. A., Guzman, C. A., Xargay, H. D., et al. Study of acoustic emission in a compression test of andesite rock. Procedia Materials Science, 2015, 9: 292-297.

Gan, Y., Wu, S., Ren, Y., et al. Research on the evaluation index of granite splitting damage based on acoustic emission rise time/ampitude and average frequency value. Rock and Soil Mechanics, 2020, 41(7): 2324-2332. (in Chinese)

Gautam, P. K., Verma, A. K., Jha, M. K., et al. Effect of high temperature on physical and mechanical properties of Jalore granite. Journal of Applied Geophysics, 2018, 159: 460-474.

Gérard, A., Genter, A., Kohl, T., et al. The deep EGS (Enhanced Geothermal System) project at Soultz-sous-Forets, Alsace, France. Geothermics, 2006, 35(5-6): 473-714.

Ge, Z., Sun, Q. Acoustic emission (AE) characteristics of granite after heating and cooling cycles. Engineering Fracture Mechanics, 2018, 200: 418-429.

Huang, S. P. COMMENTARY: Geothermal energy in China. Nature Climate Change, 2012, 2(8): 557-560.

Hu, J., Xie, H., Gao, M., et al. Damage mechanism and heat transfer characteristics of limestone after thermal shock cycle treatments based on geothermal development. International Journal of Rock Mechanics and Mining Sciences, 2022, 160: 105269.

Hu, J., Xie, H., Li, C., et al. Effect of cyclic thermal shock on granite pore permeability. Lithosphere, 2021, 2021(Special 5): 4296301.

Hu, J., Xie, H., Li, C., et al. Evolution mechanism of perme ability of hot dry rock under coupled effect of thermal fatigue and seawater interaction during coastal geothermal development. Renewable and Sustainable Energy Reviews, 2024, 189: 114061.

Kumari, W. G. P., Ranjith, P. G., Perera, M. S. A., et al. Temperature-dependent mechanical behaviour of Australian Strathbogie granite with different cooling treatments. Engineering Geology, 2017, 229: 31-44.

Kumari, W. G. P., Ranjith, P. G., Perera, M. S. A., et al. Hydraulic fracturing under high temperature and pressure conditions with micro CT applications: Geothermal energy from hot dry rocks. Fuel, 2018a, 230: 138-154.

Kumari, W. G. P., Ranjith, P. G., Perera, M. S. A., et al. Experimental investigation of quenching effect on mechanical, microstructural and flow characteristics of reservoir rocks: Thermal stimulation method for geothermal energy extraction. Journal of Petroleum Science and Engineering, 2018b, 162: 419-433.

Li, H., Jiang, X., Xu, Z., et al. The effect of supercritical CO2 on failure mechanisms of hot dry rock. Advances in Geo-Energy Research, 2022, 6(4): 324-333.

Li, N., Zhang, S., Ma, X., et al. Thermal effect on the evolution of hydraulic fracture conductivity: An experimental study of enhanced geothermal system. Journal of Petroleum Science and Engineering, 2020, 187: 106814.

Ma, W., Yang, C., Ahmed, S. F., et al. Effects of thermophysical parameters of fracturing fluid on hot dry rock damage in hydraulic fracturing. Geomechanics for Energy and the Environment, 2022, 32: 100405.

Nejati, H. R., Nazerigivi, A., Sayadi, A. R. Physical and mechanical phenomena associated with rock failure in Brazilian Disc Specimens. International Journal of Geological and Environmental Engineering, 2018, 12(1): 35-39.

Ohno, K., Ohtsu, M. Crack classification in concrete based on acoustic emission. Construction and Building Materials, 2010, 24(12): 2339-2346.

Ohtsu, M. Simplified moment tensor analysis and unified decomposition of acoustic emission source: application to in situ hydrofracturing test. Journal of Geophysical Research: Solid Earth, 1991, 96(B4): 6211-6221.

Pan, S., Gao, M., Shah, K., et al. Establishment of enhanced geothermal energy utilization plans: Barriers and strategies. Renewable Energy, 2019, 132: 19-32.

Pathiranagei, S. V., Gratchev, I., Kong, R. Engineering prop erties of four different rocks after heat treatment. Geomechanics and Geophysics for Geo-Energy and GeoResources, 2021, 7(1): 16.

Ran, Q., Chen, P., Liang, Y., et al. Hardening-damage evolu tionary mechanism of sandstone under multi-level cyclic loading. Engineering Fracture Mechanics, 2024, 307: 110291.

Ran, Q., Liang, Y., Zou, Q., et al. Experimental investigation on mechanical characteristics of red sandstone under graded cyclic loading and its inspirations for stability of overlying strata. Geomechanics and Geophysics for Geo Energy and Geo-Resources, 2023, 9(1): 11.

Rong, G., Peng, J., Cai, M., et al. Experimental investigation of thermal cycling effect on physical and mechanical properties of bedrocks in geothermal fields. Applied Thermal Engineering, 2018, 141: 174-185.

Sagar, R. V., Prasad, B. K. R., Kumar, S. S. An experimental study on cracking evolution in concrete and cement mortar by the b-value analysis of acoustic emission technique. Cement and Concrete Research, 2012, 42(8): 1094-1104.

Salimzadeh, S., Nick, H. M., Zimmerman, R. W. Thermoporoelastic effects during heat extraction from lowpermeability reservoirs. Energy, 2018, 142: 546-558.

Shao, Z., Sun, L., Aboayanah, K. R., et al. Investigate the mode I fracture characteristics of granite after heating/-LN2 cooling treatments. Rock Mechanics and Rock Engineering, 2022, 55: 4477-4496.

Sha, S., Rong, G., Chen, Z. H., et al. Experimental evaluation of physical and mechanical properties of geothermal reservoir rock after different cooling treatments. Rock Mechanics and Rock Engineering, 2020, 53(11): 4967-4991.

Shi, X., Jing, H., Yin, Q., et al. Investigation on physical and mechanical properties of bedded sandstone after hightemperature exposure. Bulletin of Engineering Geology and the Environment, 2020, 79: 2591-2606.

Siratovich, P. A., Villeneuve, M. C., Cole, J. W., et al. Saturated heating and quenching of three crustal rocks and implications for thermal stimulation of permeability in geothermal reservoirs. International Journal of Rock Mechanics and Mining Sciences, 2015, 80: 265-280.

Sirdesai, N. N., Singh, T. N., Ranjith, P. G., et al. Effect of varied durations of thermal treatment on the tensile strength of red sandstone. Rock Mechanics and Rock Engineering, 2017, 50: 205-213.

Sun, Q., Zhang, W., Xue, L., et al. Thermal damage pattern and thresholds of granite. Environmental Earth Sciences, 2015, 74: 2341-2349.

Van Berk, W., Fu, Y., Schulz, H. M. Temporal and spatial development of scaling in reservoir aquifers triggered by seawater injection: Three-dimensional reactive mass transport modeling of water-rock-gas interactions. Journal of Petroleum Science and Engineering, 2015, 135: 206-217.

Venturini, A. M. R., Dulieu-Barton, J. M. Initial studies for AE characterisation of damage in composite materials. Advanced Materials Research, 2006, 13-14: 273-280.

Wang, J., Liang, P., Zhang, Y., et al. Classification of rock tension-shear fracture based on acoustic emission RA-AF values with kneedle algorithm. Chinese Journal of Rock Mechanics and Engineering, 2024, 43(S1): 3267-3279. (in Chinese)

Wang, J., Xie, L., Xie, H., et al. Effect of layer orientation on acoustic emission characteristics of anisotropic shale in Brazilian tests. Journal of Natural Gas Science and Engineering, 2016, 36: 1120-1129.

Watanabe, H., Murakami, Y., Ohtsu, M. Quantitative evaluation of damage in concrete based on AE. Zairyo, 2001, 50(12): 1370-1374. (in Japanese)

Weng, L., Wu, Z., Liu, Q. Influence of heating/cooling cycles on the micro/macrocracking characteristics of Rucheng granite under unconfined compression. Bulletin of Engineering Geology and the Environment, 2020, 79: 1289-1309.

Xi, Y., Wang, H., Jiang, J., et al. Impacts of different cooling methods on the dynamic tensile properties of thermaltreated granite. International Journal of Rock Mechanics and Mining Sciences, 2023, 169: 105438.

Yang, F., Wang, G., Hu, D., et al. Influence of water-rock interaction on permeability and heat conductivity of granite under high temperature and pressure conditions. Geothermics, 2022, 100: 102347.

Yang, S., Ranjith, P. G., Jing, H., et al. An experimental investigation on thermal damage and failure mechanical behavior of granite after exposure to different high temperature treatments. Geothermics, 2017, 65: 180-197.

Yin, Q., Jing, H., Liu, R., et al. Pore characteristics and nonlinear flow behaviors of granite exposed to high temperature. Bulletin of Engineering Geology and the Environment, 2020, 79: 1239-1257.

Yin, Q., Wu, J., Jiang, Z., et al. Investigating the effect of water quenching cycles on mechanical behaviors for granites after conventional triaxial compression. Geomechanics and Geophysics for Geo-Energy and Geo-Resources, 2022, 8(2): 77.

Yin, Q., Wu, J., Zhu, C., et al. The role of multiple heating and water cooling cycles on physical and mechanical responses of granite rocks. Geomechanics and Geophysics for Geo-Energy and Geo-Resources, 2021, 7(3): 69.

Yu, P., Pan, P. Z., Feng, G., et al. Physico-mechanical properties of granite after cyclic thermal shock. Journal of Rock Mechanics and Geotechnical Engineering, 2020, 12(4): 693-706.

Zhang, B., Tian, H., Dou, B., et al. Macroscopic and microscopic experimental research on granite properties after high-temperature and water-cooling cycles. Geothermics, 2021, 93: 102079.

Zhang, R., Ai, T., Gao, M., et al. Basic Theory and Experimental Research on Rock Acoustic Emission. Chengdu, China, Sichuan University Press, 2017. (in Chinese)

Zhang, W., Guo, T., Qu, Z., et al. Research of fracture initiation and propagation in HDR fracturing under thermal stress from meso-damage perspective. Energy, 2019, 178: 508-521.

Zhao, F., Sun, Q., Zhang, W. Thermal damage analysis based on physical and mechanical indices of granodiorite. Geotechnique Letters, 2020, 10(2): 250-255.

Zhou, C., Gao, F., Cai, C., et al. Effect of different cooling treatments on the tensile properties and fracture modes of granite heated at different temperatures. Natural Resources Research, 2022, 31(2): 817-833.

Zhu, D., Fan, Y., Liu, X., et al. Characteristics of acoustic emission response during granite splitting after high temperature-water cooling cycles. Sustainability, 2022, 14(20): 13601.

Zhu, D., Jing, H., Yin, Q., et al. Experimental study on the damage of granite by acoustic emission after cyclic heating and cooling with circulating water. Processes, 2018, 6(8): 101.

Zhu, D., Jing, H., Yin, Q., et al. Mechanical characteristics of granite after heating and water-cooling cycles. Rock Mechanics and Rock Engineering, 2020a, 53: 2015-2025.

Zhu, Z., Ranjith, P. G., Tian, H., et al. Relationships between P-wave velocity and mechanical properties of granite after exposure to different cyclic heating and water cooling treatments. Renewable Energy, 2021, 168: 375-392.

Zhu, Z., Tian, H., Chen, J., et al. Experimental investigation of thermal cycling effect on physical and mechanical properties of heated granite after water cooling. Bulletin of Engineering Geology and the Environment, 2020b, 79: 2457-2465.

Zolfaghari, S. M., Soltani, M., Hosseinpour, M., et al. Comprehensive analysis of geothermal energy integration with heavy oil upgrading in hot compressed water. Applied Energy, 2023, 345: 121260.

Zuo, J., Zhou, H., Fang, Y., et al. Experimental study on thermal cracking of deep granite in the Beishan region of Gansu. Chinese Journal of Rock Mechanics and Engineering, 2011, 30(6): 1107-1115. (in Chinese)