Cryogenic liquids are produced in bulk quantities in large plants called air separating units (ASUs). After the air has been liquefied in the ASU process, the components of air ― nitrogen, oxygen, argon and xenon (optional) ― are separated by conventional distillation, albeit at extremely low temperatures (-325°F [-198°C]). LIN is most commonly manufactured offsite, transported in tank trailers to the user’s site, and stored in an insulated storage vessel. The LIN inventory can be managed remotely with automatic replenishment from the vendor. For large users, an ASU can be co-located at the use point.

LIN can produce severe tissue burns, so cryogenic systems must be insulated properly. When heated, LIN will expand to more than 600 times its original volume. Piping delivery systems therefore should be validated by a cryogenic specialist prior to design and commissioning.

Nitrogen gas is a simple asphyxiant, and adequate ventilation must be provided to prevent the ambient oxygen concentration from reaching dangerously low levels. However, unlike many other refrigerant chemicals, nitrogen is nontoxic and is not a greenhouse gas and therefore can be vented into the atmosphere with no negative consequences. This capability makes post-process handling relatively straightforward since no provisions for recovery of the nitrogen are required. The gas simply can be vented to a safe location.

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