| Blanketing and inerting |
Nitrogen is used to maintain a dry inert atmosphere over chemicals during storage,
reaction or processing. |
| Controlled atmospheres |
The atmosphere and ambient temperature surrounding naturally respiring products such
as fruit is actively controlled to provide optimum conditions for long-term storage. |
| Cryosurgery |
Nitrogen is used to safely remove skin lesions such as warts, tags and verrucas in both
humans and animals by the use of spray tips or probes attached to a cryogenic applicator. |
| Electronics |
Used in the inerting of printed circuit board reflow and wave ovens, to prevent oxidation
and facilitate the use of weaker fluxes that decompose more easily without leaving a residue. |
| Food freezing/chilling |
Liquid nitrogen freezes food quickly, producing a higher-quality product compared
to conventional refrigeration. |
| Food inerting |
Used in brewing, soft drinks and wine-making industries to exclude air from the product and de-aerate water. The nitrogen keeps oxygen from damaging stored foods, preventing fats' and other nutrients' decomposition. |
| Food packaging |
Used in modified atmosphere packaging, liquid nitrogen can increase the shelf-life
without the need for vacuum-packing, artificial preservatives or freezing. |
| Freeze-drying |
In the freeze-drying process, materials dissolved in water or organic solvents are
frozen into particles or droplets. A vacuum is applied to the freezing chamber along
with a controlled amount of heat sufficient to drive off moisture by sublimation. |
| Glass |
Nitrogen and hydrogen are used in the float glass process for manufacturing flat glass.
In this process, perfectly flat glass with a very high quality is achieved by floating liquid
glass on a bath of molten tin. |
| Heat treatment |
Pure nitrogen is used to protect some of the most reactive metals during heat treatment.
These metals readily form a protective oxide surface layer from the small amount of
oxygen in the nitrogen and need no further protection. |
| Lasers |
Nitrogen is used as an assist gas for laser cutting of stainless steel, aluminium
and non-metallic materials. |
| Metals |
Nitrogen is used in iron and steelworks applications for degassing and metal-stirring,
purging, cooling, slag splashing, gas knives and as a carrier gas for injecting desulphurising
compounds. It is also used for aluminium-extrusion inerting. |
| Pipe-freezing |
Repairs can be made to a pipe containing a liquid by using liquid nitrogen to freeze
a plug of liquid on each side of the section of pipe to be opened. |
| Purging |
Applications include inerting reactors and storage tanks, purging vessels and pipelines of
flammable or toxic gases and vapours, and the sparging and pressure transfer of liquids. |
| Shrink-fitting |
Liquid nitrogen is used to shrink components so they are small enough to be inserted
into another component. |
