Where to obtain a small amount of liquid nitrogen in north Seattle?

May 4, 2009 11:51 AM

Where to obtain a small amount of liquid nitrogen in north Seattle?

First off, yes I am aware that this stuff can be extremely dangerous if not handled properly. And no this is not going to be used for anything illegal or blatently stupid.

That said, I need a small amount (preferably less than a liter) of liquid nitrogen. It would be great if I could pick it up in north Seattle (U-District for preference). I do not have any university or student access.

Anyone know if this is possible? And if so, roughly how much it will cost?

posted by Riemann to shopping (7 comments total)

Not sure.

However, the NitroCream makes ice cream from liq-nit for you. It was profiled in Seattle Food Geek, so I'm guessing they're sold in Seattle.
posted by CaptKyle at 11:58 AM on May 4

You can check airgas, they sell welding supplies and other materials. The bigger expense is not the liquid nitrogen itself, priced per gallon it is less than milk, it is the transportation vessel so you can take it home with you.

If you just need a super chilled liquid, Seattle Mefite / Mad Scientist Bill Beaty may be able to give you some help.
posted by mrzarquon at 12:18 PM on May 4

Here is a reply from my friend Terence, who really knows about this kind of stuff:
==============================================================
Praxair
http://www.praxair.com/na/us/praxairSL.nsf/StoresLoc

Praxair Distribution, Inc.
215 NW 36th Street
Seattle, WA 98107
USA
Tel.: [phone]
Fax: [phone]

All their stores should carry it, but call ahead and check first.

a 10L dewar is about $60 to fill. due to evaporative losses, it's probably $30 to fill a 1L thermos. (Most of the cost in filling something small is the cost to cool the container down)

DO NOT USE ANYTHING BUT STAINLESS THERMOS!

Glass bulb thermos will implode due to thermal shock.
Plastics will form microscopic stress fractures, which allows the liquid nitrogen to seep through. This then builds up pressure inside the containment vessel and blows the two layers apart with enough force to shatter ceiling tiles.
i know both of this from experience. :-(

Stainless steel thermos - made by Aladdin, avail from Fred Meyer, is the way to go.
posted by matildaben at 12:21 PM on May 4 [1 favorite]

Of course a stainless steel thermos would work, I was always looking at the bigger vessels used in my science classes (and liquid nitrogen is actually pretty cheap, it is a byproduct of them making other liquid gases, the expense is in transportation and storage of it).
posted by mrzarquon at 12:27 PM on May 4

Many welding supply shops will have LN2 for sale. However, they *will not* sell it to you unless you have a proper container, which is a non-sealable dewar flask. They won't let you use a glass or steel vacuum flask with a screw-in stopper, because someone will screw it in, the pressure will build up, and it'll explode.

The question is "will they also rent the dewar?" In the trade, this is often referred to as "demurrage" in large volume situations, where the dewar stays on site and is filled from a truck on a regular basis.

I would call your local welding supply companies (at least, the ones that mention LN2 or Cryogen in their adverts) and ask "Hi. I'd like to make ice cream. Can I rent a 2 to 4 liter dewar and purchase that much LN2 from you?" In terms of cost-per-unit, this is very expensive, in terms of what you'd pay for the LN2, it'll be noise -- I doubt it'll cost $15 to fill a 4L Dewar.

As mentioned, Airgas is the biggest supplier, and they have a few locations in the Seattle Area. They'll almost certainly be near the big industrial areas.
posted by eriko at 12:36 PM on May 4

Depending on what you're trying to do, consider dropping dry ice into any mostly-pure alcohol e.g. ethanol, meths, (iso)propanol, etc. The alcohol will chill to the dry ice temp (-83 centigrade or lower) and stay liquid. This is quite a bit warmer than liquid N2, but still useful as a coolant, to snap-freeze stuff, etc. If you can use this instead, dry ice and an industrial alcohol are both considerably easier to buy and transport.
posted by metaBugs at 12:54 PM on May 4

A 10L dewar is about $60 to fill. due to evaporative losses, it's probably $30 to fill a 1L thermos.

Yikes. This might be a good time to make friends with a science grad student. The price is something like 16¢/liter at my university stockroom.
posted by halogen at 4:13 PM on May 4