Making Liquid Air in Small, Economical Quantities

A mixing apparatus combines liquid oxygen and liquid nitrogen to make liquid air in small, convenient quantities. Heretofore, equipment used to make liquid air by mixing was incapable of making batches smaller than 600 gallons (2,300 L). The present mixing apparatus produces liquid air on demand in batches as small as 100 liters; a batch of this size is suitable for filling self-contained breathing apparatuses like those worn by firefighters and others working in hostile environments.