Development of a high efficient NH3/CO2 refrigeration system.

Environmental problems such as ozone layer depletion and global warming are widely known as global issues. The Montreal Protocol totally prohibits use of HCFC from 2020 and Kigali revision of the protocol calls for gradual reduction of use of HFC by 85% towards 2036. In the industrial refrigeration, HCFC-22 refrigerant has been used for many years and HFC refrigerants are widely used as alternatives, however, conversion to refrigerants with less environmental impact is urgently required. Mayekawa developed and introduced a highly efficient refrigeration system called ‘NewTon’, applying the natural refrigerants ammonia (NH3) and carbon dioxide (CO2) as the primary and secondary refrigerants. The refrigeration system demonstrates a high energy saving compared to systems with traditional working fluids and in addition its direct environmental impact can be neglected since only natural working fluids are applied. These kind of units are widely used in freezing- and cold storage applications. In this work, the specific features of the ‘NewTon’ unit are described and energy consumptions are compared with historical demands of the systems, which have been replaced.