Nitrogen is a true
„all-rounder“ among gases. Thus, for example, it is used as an inert gas by the
chemical industry, in the food technology industry, and in metallurgy and, in
its cryogenic, liquefied form, it is employed tofreeze foods, to recycle
composite materials, to preserve biological materials, as a coolant in the
treatment of rheumatism, as a refrigerant for cryosurgery, and also for
tire filling. One could easily
list nearly a hundred applications for this gas alone. This profusion of
applications is based on the exploitation of two basic principles, either
individually or together: one makes use of either nitrogen’s low reactivity or
its cold in its cryogenic, liquefied form. As a so-called „protective gas“,
nitrogen displaces the oxygen in the air which can be damaging or even hazardous
to many processes. In its liquefied form (at a temperature of minus 196 °C)
nitrogen is a refrigerating agent with numerous applications.