Research and Development

Development of a process fluid for high temperature heat pumps

High temperatures of 90 ° C to approximately 120 ° C are required for many industrial processes. This is used primarily for the production of hot water or low pressure steam. Due to the special technical conditions in high temperature heat pumps it is only possible to use refrigerants with low pressures and high critical temperatures for this. In the past the CFC refrigerant R114 was used for this. Its transitional replacement by HCFC R124 was only temporary, so a longer-term solution with an HFC refrigerant was urgently needed.

The industrial partners Schwier refrigeration, air conditioning and electrical engineering, Barenbrug, and P. Comte electroplating technology GmbH & CO. KG, Sulingen, were looking for a replacement refrigerant mixture together with the research partners Solvay Fluor GmbH, Hanover, and the Institute for Thermodynamics, Helmut Schmidt University / the Armed Forces University in Hamburg. In this case the zoetrope refrigerant mixture R365mfc/R227ea was proven favourable, since the evaporation and condensation could be adapted for gradually changing temperatures and gradual cooling of the heat source or gradual heating of the heat sink, which resulted in energy advantages when used in heat pumps that warm or cool material flows.
After testing the thermo-physical properties, doing chemical thermal studies and machine trials a field test facility as a high-temperature heat pump for industrial application was designed, installed put into operation and metered.

Field Test

The high temperature heat pump was constructed by Schwier. The on site installation of the system and the integration into the hydraulic system was then carried out by Comte together with Schwier.