[S-RD24] Cutting-edge sensing technology applied to geology and resource exploration

[SRD24-04] Experimental Study on Reservoir Disturbance Characteristics During Deep Reinjection of High-Salinity Mine Water

*Shiang Xu^1,2, Chaoqiang Xi², Shenglin Li¹, Huanqin Yun², Xiongwu Hu², Yali Peng², Yuchan Xiong² (1.State Key Laboratory of Digital and Intelligent Technology for Unmanned Coal Mining Anhui University of Science and Technology, 2.School of Earth and Environment Anhui University of Science and Technology)

Keywords:high-salinity mine water, deep underground injection, reservoir disturbance, distributed optical fiber sensing

Mining activities are accompanied by the discharge of a large amount of mine water, among which the treatment of high-salinity mine water has become a critical challenge in mining production. Deep underground injection technology offers a potential solution for the treatment and sequestration of high-salinity mine water. However, current research predominantly focuses on water quality treatment, while the effects of water-rock interactions and reservoir formation disturbances caused by deep injection remain underexplored. To address this gap, this study constructed a 1:400 scaled physical simulation model based on the geological conditions of a mining area in western China. The model simulated the injection of high-salinity mine water into the Liujiagou Formation at depths of 1620–1990 meters. A distributed optical fiber sensing (DOFS) system was designed to capture the diffusion characteristics and reservoir response during the injection process. Furthermore, the study compared the differences between continuous and intermittent injection modes in terms of high-salinity mine water sequestration and overlying formation disturbances. The results demonstrate that DOFS technology can effectively characterize the temporal and spatial evolution of reservoir disturbances during deep injection. Additionally, continuous injection resulted in more concentrated and intense disturbances within the reservoir, whereas intermittent injection caused less severe but more widespread disturbances. These findings provide valuable theoretical and technical insights for the development of deep underground injection technology for high-salinity mine water.