Food Engineering
TECH FLASH

Reuse waste heat from refrigeration units

March 13, 2012
Dutch Refrigeration Prize
John van Rooijen (right), technology & innovation manager at GEA Refrigeration Netherlands, received the Dutch Refrigeration Prize from Vincent Slappendel (left), director of NVKL, and Dr. ir. C.A. Infante Ferreira, TU Delft and member of the jury.

GEA Refrigeration Netherlands N.V. won the Dutch Refrigeration Prize last month for technology that combines a refrigerating plant and a heat pump. The Dutch Association of Companies in the Field of Refrigeration Technology and Air Treatment (NVKL) has awarded this prize since 1989 to recognize innovations in the area of refrigeration and HVAC.

The Energy Enhancer, the name given by GEA to this refrigeration-heat solution, convinced the contest jury of its energy-savings potential. The solution uses an ammonia heat pump to raise the temperature of the heat exhausted from refrigeration compressors (originally emitted at about 35°C [95°F]) to a level of 80°C (176°F), which can be effectively used as a heat source for processes throughout the plant. This enables efficient use of heat in, for example, milk pasteurization, French fries production (blanching) and meat processing (cleaning machines). The heat can also be used anywhere else it’s needed, such as in heating the plant’s environment.

The Energy Enhancer raises exhausted heat—which is often dissipated into the environment without being used in conventional refrigeration units—to a higher temperature, where it becomes useful energy. This can eliminate the need to produce heat by gas-fired, hot-water heaters or steam generators.

A gas boiler requires approximately 120 kW in the form of gas input to produce 100 kW of useful heat, whereas the combined system requires only 20 kW of electrical power to deliver the same thermal output. This enables not only significant reduction in operating costs, but also leads to a large reduction in CO2 emissions.