For low potential hot spring, the surface water temperature lower
than 60ºC has been used in drying process by using vapor compression
heat pump (VCHP) to upgrade heat to be around 70°C and supply into
drying room. The working steps of the drying room with heat pump
system start with the hot water enters the system as shown in Figure
9. The hot water transfers heat to the working fluid, which evaporates
accordingly. The resultant vapor is then pressurized by the compressor.
After that, upgrading heat is extracted at the condenser and sent into
heating coil in the drying room. The air inside the room is then heated
by the heating coil.