Following an energy audit to improve the energy efficiency for the replacement of the existing HCFC-22 refrigeration system, a German chocolate producer has decided on an optimized HFC-134a based concept.
Chocolate is temperature sensitive and the temperature in its production process steps must be reliably and carefully controlled. The HCFC-22 refrigeration system was designed to deliver 2 °C circulating brine to the plant, brine which was further brought to the required temperature needed for each different user.
The simple replacement of the cooling fluid would have been the cheapest solution, but would have been detrimental to energy efficiency. The company therefore decided to have an energy audit which would propose an optimized solution for the replacement of the HCFC-22 refrigeration unit, delivering optimal energy efficiency, operations flexibility, together with an acceptable payback time.
The design of the new system is based on a centralized system with four interconnected compressors specially designed for the HFC-134a refrigerant. Two compressors, of 3.85 and 2.1 MW, installed first, have achieved an EER (Energy Efficiency Ratio : the ratio of the actual cooling achieved relative to the power consumed) between 7 and 8, twice the efficiency of the replaced system, and an ESEER (European Seasonal Energy Efficiency Ratio) up to 8.1.
To optimize the plant energy efficiency, compressors are working with the total thermal load distributed on several machines in parallel, therefore running on energy-saving partial load mode, and the cooling capacity is distributed to the different brine circuits at their specifically required temperature.
Source (requires subscription): Die Kaelte