Geothermal Deicing in a Mine Tunnel

Abstract

The floor of the entrance tunnel to an underground waste deposit system in Hungary is exposed to frost and icing in winter. This is rather dangerous for the heavy vehicle traffic. To avoid this danger, a floor deicing system was installed. This consists of a heating grid system placed in the floor of the tunnel entrance section. Initially, a fuel oil system was utilized to heat the incoming air. More recently geothermal heat pumps were recommended for the expansion of the facility. In this case geothermal energy is utilized indirectly by two different systems. The first is air-water heat pumps utilizing the heat content of the warmed up air as it flows out of the mine tunnel. The other source is the heat content of the drained water from the deep part of the mine. The benefit of this system is multiplied: decreasing of the thermal power as compared to the original fuel oil heating system, eliminating of the use of fuel oil, and decreasing the CO2 emissions.