Cheers to that!
An innovative brewery refrigeration system that uses natural CO2 gas has been conceived by engineers from the Ziemann Group in collaboration with Axima. This system, which will be of particular interest to large plants with extensive pipe networks and high energy requirements, uses CO2 instead of both a refrigerant and a refrigerating agent to cool fermentation and storage tanks. A compressor is used to liquefy the CO2, replacing the heat exchanger previously used. As an evaporating refrigerant, liquid CO2 can obtain temperatures as low as -10°C. Up until now, ammonia has been used as refrigerant in most breweries, cooling to a temperature of -6°C. The secondary fluid usually used is glycol, which is cooled by ammonia via a heat exchanger. With the CO2 system, evaporation takes place directly. CO2 offers numerous advantages including the fact that it is already used in the brewing process and thanks to its higher volumetric capacity, pipework, pumps and insulation can be designed with smaller cross-sections. It has no detrimental effect on the contents of the tank, the cooling process uses less energy use requires no safety engineering restrictions or approval procedures. Although CO2 requires a higher initial investment given its high operating pressure and high level of know-how, breweries seeking overall optimum efficiency in the long term are likely to be relying on CO2 refrigerating technology in the very near future.