REFRIGERANT CIRCULATION DEVICE, METHOD FOR CIRCULATING REFRIGERANT AND ACID SUPPRESSION METHOD

摘要

The purpose of the present invention is to provide a heat pump device and an organic Rankine cycle device, each of which is capable of maintaining a stable thermal cycle even if HFO is used as a refrigerant in an environment where the operating temperature thereof is high. This refrigerant circulation device (1) is filled with a refrigerant that contains a hydrofluoroolefin or hydrochlorofluoroolefin having a carbon-carbon double bond in each molecular structure, and this refrigerant circulation device (1) has a region where the operating temperature of the refrigerant is 175°C or more in the refrigerant circulation circuit. The region where the operating temperature of the refrigerant can be 175°C or more is provided with an acid suppression unit (6) for suppressing increase of the acid concentration in the refrigerant, and the acid suppression unit (6) contains an acid suppression material that is mainly composed of at least two materials selected from the group consisting of copper, iron, aluminum, SUS, nickel, titanium, silicon metal, silicon carbide, tin, magnesium and zinc.