[SBE] Nitrogen

[Mike Langner]

Liquid carbon dioxide "boils" at standard pressure at -127.4 degrees F.

Liquid nitrogen "boils" at standard pressure at -195.8 degrees F.

Under pressure, of course, the boiling temperatures for both (indeed as far
as I know for all) liquids increases -- think about your mom's stovetop
pressure cooker. . .

Liquid nitrogen is lots harder to handle. . .

Liquid oxygen is even harder to handle (colder), but hospitals do it.

Still, compressed gas cylinders are sure easy to work with!

By the way -- as I'm sure you know -- dry nitrogen and "oil pump nitrogen"
are not interchangeable for many uses, including, according to nearly all
sources, transmission line pressurization.

Interesting, thought provoking stuff!

Mike/

Mike Langner, CPBE

Albuquerque, NM
_______________________________________

  -----Original Message-----
  From: sbe-bounces at sbe.org [mailto:sbe-bounces at sbe.org]On Behalf Of
Humphrey, Richard A
  Sent: Thursday, May 07, 2009 9:41 AM
  To: sbe at sbe.org
  Subject: Re: [SBE] Nitrogen


  There is a restaurant near one of my towers which gets CO2 for the soda
machine delivered in liquid form.  They have a cryogenic tank and gas
generator next to the road.  So if a pizza place can do this with CO2, there
should be off the shelf hardware available for storing liquid N2 and turning
it into gas as needed that would work for transmitter engineers.  The
semiconductor industry goes through a lot of nitrogen and other gasses.
This is how they do it.  But it's probably cheaper just to plug in a
dehydrator and use dry air.

  Richard Humphrey

  KMAX/KOVR-TV
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