PURPOSE: To obtain a multistage refrigerator and a method for refrigerating in a multistage in which power consumption in the daytime, at night, etc., can be leveled and further the power consumption can be largely reduced.
CONSTITUTION: The multistage refrigerator comprises a plurality of compressors 20, 21 arranged in series, a cooling refrigerant tube 29 supplying the part of refrigerant as cooling refrigerant of an intermediate cooler 23 via a switching valve 27 to the refrigerant tube 26 of a refrigerating cycle having the cooler 23, a second condenser 30 provided between the valve and the intermediate cooler, expansion means 32 for cold thermal storage material cooler and cold thermal storage material cooler 33 arranged at a refrigerant tube, a cold thermal storage material cooling tube 34, a supply tube 37 for introducing cold thermal storage material into the second condenser provided between the cooler and the second condenser, a return tube 38 for introducing the material to the cooler, and cold thermal storage material feeding tube having a cold thermal storage material pump 39 for feeding the material.
HIRAMATSU MASAYOSHI
HIRANO MASAYOSHI
KAWAMURA KAZUSHIGE
AWAI EIJI
KINOSHITA AKIRA
CHIYODA CHEM ENG CONSTRUCT CO