Cryogenic transport medium or regenerator purification method, regeneration method, air conditioner maintenance method, refrigeration transport medium or regenerator purifier, regenerator, air conditioning system

摘要

PROBLEM TO BE SOLVED: To provide a purification method which suppresses precipitation of a water-soluble inorganic salt from a cold transfer medium or a cold storage material containing an aqueous quaternary ammonium salt solution as a main ingredient.SOLUTION: This method comprises: a concentration step of performing concentration by removing water from the cold transfer medium or the cold storage material containing the aqueous quaternary ammonium salt solution as the main ingredient; a two-layer-separating step of leaving the concentrated cold transfer medium or cold storage material at rest to be separated into a light solution layer with a low specific gravity containing a quaternary ammonium salt and a water layer with a high specific gravity containing a water-soluble inorganic sa and a water layer-removing step of removing the water layer from the cold transfer medium or the cold storage material separated into the two layers, wherein the two-layer-separating step includes a heating keeping step of keeping the temperature of the concentrated cold transfer medium or the cold storage material in a predetermined temperature range in which any water-soluble inorganic salt is not precipitated and any deterioration of the quaternary ammonium salt does not occur; and, in the concentration step, the cold transfer medium or the cold storage material is concentrated in a concentration range which is less than the concentration at which the water-soluble inorganic salt is precipitated in the predetermined temperature range.