Method to convert excess liquid oxygen into liquid nitrogen

A method for exchanging heat between an excess liquid oxygen stream with a gaseous nitrogen stream to produce an additional liquid nitrogen stream, comprising:

• introducing a gaseous nitrogen stream into a main heat exchanger, therein indirectly exchanging heat with a vaporized oxygen stream, a vapor phase nitrogen steam, and a waste liquid nitrogen stream;
• thereby producing a cold gaseous nitrogen stream, a warm oxygen vent stream, a warm nitrogen vent steam, and a warm gaseous nitrogen waste stream,
• introducing the cold gaseous nitrogen stream into a secondary heat exchanger, therein indirectly exchanging heat with a liquid oxygen stream;
• thereby producing the vaporized oxygen stream and a cold liquid nitrogen stream,
• introducing the cold liquid nitrogen stream into a nitrogen pressure reduction valve thereby producing a two-phase nitrogen stream,
• introducing the two-phase nitrogen stream into a nitrogen flash vessel thereby producing a liquid phase nitrogen stream and the vapor phase nitrogen stream,
• wherein the method is performed in the absence of refrigerant turbo-expanders, refrigerant expansion turbines, or refrigerant compressors.