文献类型：期刊文献

英文题名：A study on pore-scale fracture deformation induced by the CO2-H2O-minerals reactions in CO2-based Enhanced Geothermal Systems

作者：Yang, Jiajie[1];Wang, J. G.[2,3];Li, Peibo[1];Leung, Chunfai[1,4]

机构：[1]China Univ Min & Technol, State Key Lab Geomech & Deep Underground Engn, Xuzhou 221116, Peoples R China;[2]Shaoxing Univ, Sch Civil Engn, Key Lab Rock Mech & Geohazards Zhejiang Prov, Shaoxing 312000, Peoples R China;[3]China Univ Min & Technol, Sch Mech & Civil Engn, Xuzhou 221116, Peoples R China;[4]Natl Univ Singapore, Dept Civil & Environm Engn, Singapore 117576, Singapore

年份：2025

卷号：250

外文期刊名：GEOENERGY SCIENCE AND ENGINEERING

收录：SCI-EXPANDED(收录号：WOS:001456242900001)、、EI(收录号：20251218080962)、Scopus(收录号：2-s2.0-105000230667)、WOS

基金：The authors are grateful for the financial support from the Funda-mental Research Funds for the Central Universities (Grant No. 2024-10970) , the Postgraduate Research & Practice Innovation Program of Jiangsu Province (Grant No. KYCX24_2703) , the Graduate Innovation Program of China University of Mining and Technology (Grant No. 2024WLKXJ189) , and National Natural Science Foundation of China (Grant No. 51674246, 42030810) .

语种：英文

外文关键词：Hot dry rock; Enhanced geothermal systems; Supercritical carbon dioxide; Mineral dissolution and precipitation; Reaction kinetics equations; Fracture deformation

外文摘要：CO2-based Enhanced Geothermal Systems (EGS) contain supercritical CO2 and a trace amount of water. This may trigger CO2-H2O-minerals reactions and thus induce fracture deformation. As fractures are the primary channels of fluid flow and heat transfer, their deformation will further affect water loss and heat recovery, thus influencing the efficiency of CO2-based EGS. However, the fracture deformation at pore scale under the CO2-H2O-minerals reactions is still unclear. This study will investigate the fracture deformation mechanism and influence factors under the CO2-H2O-minerals reactions in the CO2-based EGS. Firstly, a thermal-hydraulic-chemical-deformation (THCD) coupling model is established for a two-dimensional single fracture at pore-scale to fully consider both aqueous and minerals reactions. Then, the fluid flow, heat transfer, mineral reactions, and fracture deformation in the single fracture are numerically simulated under the CO2-H2O-minerals reactions. Finally, the effects of temperature and flow rate on fracture deformation are explored. It is found that the dissolution of feldspar minerals causes the primary fracture deformation. Temperature directly alters the reaction rate and flow rate changes the convective heat transfer efficiency and temperature distribution. The increase of temperature or the decrease of flow rate will result in greater fracture aperture expansion. Over 30 years, the average fracture aperture increases by nearly one-fold if the inlet temperature is 180 degrees C and exceeds 80 % if the injection flow rate is 10 mm/s. This implies that fractures near the production well (with higher temperature) or in low connectivity zones (with slower flow rate) experience more significant aperture expansion in CO2-based EGS. These results may be of great significance for the efficient development of CO2-based EGS.