Abstract
Underground mines in China are rich in geothermal resources. Based on backfill mining technology, the collaborative development of deep mineral resources and geothermal resources can be realized. The key of this approach is to form artificial thermal reservoirs by heat storage backfill body and to extract geothermal energy as much as possible through the built-in pipe. It is important to investigate the backfill material and system parameter design to improve the heat storage and release performance of backfill body and enhance the extraction efficiency of geothermal energy in mine. In this paper, experimental and simulation studies of backfill coupled heat exchanger system with different backfill materials are carried out to make a comparative study. The backfill materials involved include traditional backfill material, natural flake graphite backfill material and paraffin RT28 backfill material. After comparing the heat storage and heat release behavior, liquid fraction variation and efficiency of different systems, the natural flake graphite backfill body which has better engineering value is selected to further conduct experiments to study the influence of surrounding rock temperature, initial temperature of backfill body and inlet water temperature on the thermal performance of the system. The results show that with the increase of surrounding rock temperature, initial temperature of backfill body, or the decrease of inlet water temperature, the total heat storage, heat release and energy utilization coefficient of the system all increase. When the initial temperature of backfill is 26 °C, surrounding rock temperature is 45 °C, inlet velocity and temperature are respectively 0.7 m/s and 18 °C, the energy utilization coefficient of the system is the highest, which is 81.4%. The research results are helpful to the design of heat storage backfill body and the improvement of thermal performance of the system.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.