Until recently, the HVAC&R operations at Meat World – a wholesale and retail butchery group with 11 meat shops across South Africa – had been based on HFCs. Keen to improve the efficiency of its industrial operations, the firm chose a CO2 transcritical refrigeration system for its new meat processing plant in Johannesburg.
Beijer Ref companies SCM Frigo and Metraclark – the largest refrigeration and air-conditioning wholesaler in Southern Africa – provided the CO2 transcritical system, which was installed by Coolcare and commissioned in April 2018.
“Since the commissioning, the customer has been very satisfied in terms of the system’s operation and its efficiency,” Mirko Bernabei, technical director at SCM Frigo, told Accelerate.
The CO2 system keeps the plant’s 7,500 m3 processing area at a constant temperature of 10°C. It also serves 18,000 m3 of freezing space and a 720 m3 pull-down freezer, cooling both to -20°C. The system maintains 2,500 m3 of cold rooms at 0°C.
The system comprises two SCM Frigo outdoor CO2 transcritical units, each equipped with four Bitzer medium-temperature compressors, four Bitzer low-temperature compressors, and two Bitzer parallel compressors. The units, installed as walk-in boxes, also feature one Danfoss vapour multiejector and one Luvata gas cooler.
Moreover, the CO2 system provides air conditioning up to a total load of 60 kW. Heat recovered from the system provides the plant with hot water at 50°C for production operations.
With parallel compression, Bernabei expects the CO2 transcritical system to save 6% on energy consumption compared to the R404A solution typically installed in such plants. The vapour ejector delivers another 7% energy saving in high ambient temperatures. The total energy saving vs. the R404A option is therefore 13%.
Meat World didn’t have any prior experience of CO2 but after considering factors such as reliability, power consumption, installation costs and maintenance, they opted for CO2. “In the process, we had several technical training sessions via web conference, as well as face-to-face meetings.” Bernabei adds.
Beijer Ref’s new ‘SCM Ref Africa’ OEM segment in South Africa gives the group the ability to manufacture SCM products locally.