New CO₂ plant for UK food-processing company

Greencold has installed a new CO₂-based cooling plant at a food-processing firm in the United Kingdom. The plant, which has a cooling capacity of 180 kW, comprises six identical cooling chambers for low-temperature blast chilling of meat down to -20° C. 

For the end user, the choice of CO₂ was motivated by price and the desire for future-proof technology, according to Greencold. 

The customer initially considered an ammonia-based pumped recirculation system. But this was subsequently ruled out due to price, space, delivery time and specific site safety considerations. 

Another option would have been to use a direct expansion system with HFC R407F, but the end user ruled this out amid the HFC phasedown, rising refrigerant prices and the mass of the refrigerant required. 

A pumped system with CO₂ was also considered, but again this was ruled out due to the significantly higher cost of including the required low-pressure station vessel and skid. Space was also lacking for such a system. 

The system chosen is a direct expansion system with approximately 300 kg of CO₂. The freezer suction line pressure is typically around 15 bar and the average freezer liquid line pressure is approximately 25 bar.