Method for recycling argon

A method for reutilizing argon in an industrial process, in which argon kept in stock in the liquid state in a tank (pure argon) is taken from the tank, vaporized and fed in gaseous form to an industrial process, wherein:

• a. the gaseous argon which has been used in the industrial process (crude argon) is compressed in a compressor;
• b. the compressed crude argon is fed to a main heat exchanger and cooled there by indirect heat exchange with at least one first cooling medium;
• c. the compressed and cooled crude argon is fed to a separation device and cooled there by heat exchange with a second cooling medium to a temperature below the boiling point of argon at the pressure prevailing in the separation device, resulting in a gas phase composed of argon contaminated with low boilers and a liquid phase composed of argon which has been at least largely freed of low boilers (product argon) being formed;
• d. the gas phase is at least partly taken off from a head space of the separation device;
• e. the product argon is taken off in the liquid state from a bottom region of the separation device, depressurized and used in the main heat exchanger as cooling medium for cooling the crude argon, resulting in it vaporizing;
• f. the vaporized product argon is at least partly recirculated to the industrial process;
• g. where liquid pure argon is taken from the tank and brought into direct or indirect thermal contact with the crude argon in order to cool the crude argon in the separation device and/or during feeding of the crude argon to the separation device.