Although supercritical carbon dioxide(SC-CO_(2))fracturing shows tremendous potential for maximizing injection efficiency and enhancing storage volumes,few investigations have been reported on the SC-CO_(2) fracturing...Although supercritical carbon dioxide(SC-CO_(2))fracturing shows tremendous potential for maximizing injection efficiency and enhancing storage volumes,few investigations have been reported on the SC-CO_(2) fracturing characteristics of tight basalts and the reactions between fractured basalt and SC-CO_(2).In this study,hydraulic fracturing experiments were conducted on cylindrical basalt specimens using water and SC-CO_(2) as fracturing fluids.Geometric parameters were proposed to characterize the fracture morphologies based on the three-dimensional(3D)reconstructions of fracture networks.The rock slices with induced fractures after SC-CO_(2) fracturing were then processed for fluid(deionized water/SC-CO_(2))-basalt reaction tests.The experimental results demonstrate that SC-CO_(2) fracturing can induce complex and tortuous fractures with spatially dispersed morphologies.Other fracturing behaviors accompanying the acoustic emission(AE)signals and pump pressure changes show that the AE activity responds almost simultaneously to variation in the pump pressure.The fractured basalt blocks exposed to both SC-CO_(2) and water exhibit rough and uneven surfaces,along with decreased intensities in the element peaks,indicating that solubility trapping predominantly occurs during the early injection stage.The above findings provide a laboratory research basis for understanding the fracturing and sequestration issues related to effective CO_(2) utilization.展开更多
The corrosion behavior of 304LN austenitic stainless steel in supercritical CO_(2) at 650℃ was investigated.The results show that 304LN follows Wagner’s law kinetics,forming a protective oxide flm consisting of SiO_...The corrosion behavior of 304LN austenitic stainless steel in supercritical CO_(2) at 650℃ was investigated.The results show that 304LN follows Wagner’s law kinetics,forming a protective oxide flm consisting of SiO_(2),(Cr,Mn)3O_(4),and Cr2O_(3) from the inner to outer layers.A shallow carburization depth of approximately 130 nm indicates excellent resistance to carburization.The roles of key elements in 18/8 austenitic stainless steel represented by 304LN,such as Cr,Ni,and Si,were analyzed,highlighting their contributions to anti-carburization performance and corrosion resistance under harsh conditions.展开更多
基金supported by the National Key Research and Development Project(Grant No.2023YFE0110900)the National Natural Science Foundation of China(Grant No.42320104003)the Shanghai Pujiang Programme(Grant No.23PJD105).
文摘Although supercritical carbon dioxide(SC-CO_(2))fracturing shows tremendous potential for maximizing injection efficiency and enhancing storage volumes,few investigations have been reported on the SC-CO_(2) fracturing characteristics of tight basalts and the reactions between fractured basalt and SC-CO_(2).In this study,hydraulic fracturing experiments were conducted on cylindrical basalt specimens using water and SC-CO_(2) as fracturing fluids.Geometric parameters were proposed to characterize the fracture morphologies based on the three-dimensional(3D)reconstructions of fracture networks.The rock slices with induced fractures after SC-CO_(2) fracturing were then processed for fluid(deionized water/SC-CO_(2))-basalt reaction tests.The experimental results demonstrate that SC-CO_(2) fracturing can induce complex and tortuous fractures with spatially dispersed morphologies.Other fracturing behaviors accompanying the acoustic emission(AE)signals and pump pressure changes show that the AE activity responds almost simultaneously to variation in the pump pressure.The fractured basalt blocks exposed to both SC-CO_(2) and water exhibit rough and uneven surfaces,along with decreased intensities in the element peaks,indicating that solubility trapping predominantly occurs during the early injection stage.The above findings provide a laboratory research basis for understanding the fracturing and sequestration issues related to effective CO_(2) utilization.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA0410000)the CAS Project for Young Scientists in Basic Research(No.YSBR-043)+1 种基金the CNNC Science Fund for Talented Young Scholars,the National Funding Program for Postdoctoral Researchers(GZC20232747)the Youth Innovation Promotion Association CAS(2022187).
文摘The corrosion behavior of 304LN austenitic stainless steel in supercritical CO_(2) at 650℃ was investigated.The results show that 304LN follows Wagner’s law kinetics,forming a protective oxide flm consisting of SiO_(2),(Cr,Mn)3O_(4),and Cr2O_(3) from the inner to outer layers.A shallow carburization depth of approximately 130 nm indicates excellent resistance to carburization.The roles of key elements in 18/8 austenitic stainless steel represented by 304LN,such as Cr,Ni,and Si,were analyzed,highlighting their contributions to anti-carburization performance and corrosion resistance under harsh conditions.
