New technology research of efficient utilization of geothermal energy

Abstract Geothermal energy is being widely valued as a clean energy source. Underground structure has a controlling influence on the geothermal development. If the underground structure can be visualized, it is the key technology to improve the geothermal development. Through the streaming potential detection technology, under the action of external pressure, the liquid can be forced to flow through the solid pores to generate directional flow, and the flow potential can be generated at both ends of the solid pores. Different streaming potential phenomena under pressure can help engineer to distinguish different geological structures. A set of laboratory tests was designed to prove the feasibility and accuracy of this proposed detection methods, and tests were conducted using the core injection system and the streaming potential tester to carry out injection on sandstone specimens of two different structures, to study the effect of different injection pressures and different salinity on variation of streaming potential in sandstone. The laboratory test results show that the flow potential is accompanied by the liquid injection process in the sandstone specimen, and the flow potential produced by the sandstone with different porosity is obviously different, so the flow potential accompanying the actual rock injection process can be used to distinguish different geological structures, and this study provides a new idea for studying geological structures, and are expected to improve the efficiency of geothermal development.