This month METRO AG, a German multinational wholesale specialist, told R744.com it had opened its first CO2 transcritical store in Croatia.
The new Dubrovnik store uses a CO2 transcritical refrigeration system together with an ejector, confirming METRO AG’s commitment to using innovative CO2 technology in new locations.
The wholesaler has opened several CO2 transcritical stores in Russia, some of which have heat reclaim and parallel compression, and in Bulgarian capital Sofia, where it retrofitted an HFC system with an ejector-based CO2 transcritical system. Similarly, in China it has led the way in opening that country’s first CO2 transcritical food retail store. It will open two more CO2 transcritical stores, with one using an ejector and another using a parallel compression system, in China this year.
The new Croatian store uses a CO2 transcritical booster system from Italian manufacturer Enex, with three low-temperature, three medium-temperature and two parallel compressors provided by Italian compressor company Dorin. Three of the compressors employ inverter technology.
Installation and assembly were carried out by ZAGI-MONT, a local company.
The CO2 system uses two Danfoss multi-ejectors. One is a high-pressure lift gas ejector, which was used to take gas from the suction accumulator to the receiver that is then compressed by parallel compressors to the gas cooler. The other is a liquid ejector, which takes the liquid accumulated in the suction accumulator during the liquid superheat evaporator mode and lifts it to the receiver to be used again by the evaporators.
Electronic controllers and CO2 gas detectors by Danfoss were also used.
The system proves a total of 119 net/145 gross kW cooling capacity at -8°C and 25 kW at -30°C for the Dubrovnik store.