A vacuum insulated evaporator (VIE) is a form of pressure vessel that allows the bulk storage of cryogenic liquids including oxygen, nitrogen and argon for industrial processes and medical applications.[1]

Diagram showing the components of a VIE system.
A photo showing a VIE system.

The purpose of the vacuum insulation is to prevent heat transfer between the inner shell, which holds the liquid, and surrounding atmosphere.[2] Without functioning insulation, the stored liquid will rapidly warm and undergo a phase transition to gas, increasing significantly in volume and potentially causing a catastrophic failure to the vessel due to an increase in pressure. To combat such an event, VIEs are installed with a pressure safety valve.

To remain a liquid, the vessel contents must be kept at or below its critical temperature. The critical temperature of oxygen is −118 °C; above this temperature, applying more pressure will not result in a liquid, but rather a supercritical fluid.[3]

References

Wikiwand in your browser!

Seamless Wikipedia browsing. On steroids.

Every time you click a link to Wikipedia, Wiktionary or Wikiquote in your browser's search results, it will show the modern Wikiwand interface.

Wikiwand extension is a five stars, simple, with minimum permission required to keep your browsing private, safe and transparent.