To provide an ammonia/CO2 refrigeration system capable of installing a refrigeration showcase or the like that is a cooler side of a CO2 cycle, in an optional place according to convenience of a customer.
This ammonia/ CO2 refrigeration system provided with an ammonia refrigerating cycle, a CO2 brine cooler 3 for cooling CO2 using evaporation latent heat of ammonia, and a liquid pump 5 for feeding liquefied CO2 to a heat exchanger (cooler) side of a cooling load has a liquid receiver 4 for receiving CO2 brine, the liquid pump formed of a feed liquid variable type forcible circulation pump, and a leading-up pipe 90 interposed between the liquid pump and a heat exchanger 6. In the refrigeration system, delivery pressure (forcibly driven flow rate) of the liquid pump is set to return the CO2 recovered from a cooler outlet in a load side to the brine cooler under a liquid or gas-liquid mixed condition (incomplete evaporation condition), and a leading-up level for the leading-up pipe is set in a level same to or higher than the maximum storage level of the CO2 brine.
TANIYAMA AKIRA
AKABOSHI SHINJIRO
TERAJIMA IWAO
Hisamaru Hanada