Heat pumps are characterized by their ability to supply thermal energy to a heat sink at a higher temperature than the heat source. The temperature increase between the heat source and the sink is created by compressing the working media (refrigerant). Usually, electricity is used as energy input to a heat pump system for the compressor. The advantage of a heat pump is that it can deliver a higher amount of thermal energy than the amount of energy that is needed for the compressor. Therefore, heat pumps are highly efficient waste heat recovery devices.
A closed loop heat pump consists of four main components: the compressor, the condenser, the expansion valve and the evaporator. The refrigerant is kept within the cycle at all times. HFO-1336mzz-Z (OpteonMZ) will be used as refrigerant for the closed loop systems. It is well suited for high temperature applications allowing for heat supply temperatures up to 160°C. It is non-flammable, non-toxic and not subject to the F-gas regulation.
The closed loop heat pumps in DryFiciency are integrated in air drying processes that are currently heated with natural gas. Waste heat from other drying processes is available at the industrial sites, where the heat pumps are demonstrated. Thus, heat recovery water cycles serve as heat source for the heat pumps. The heat sink is the drying agent (air), which is heated in a heat exchanger and provides energy for the drying processes. Thus, the natural gas consumption is substituted by a considerably smaller amount of electricity.
Demonstration planned in