This is an older thread, but people are keeping it alive, so I will put in some of my own experiences with ln2.
For every day use, yes you COULD set up a system to use ln2 on a daily basis... but Please use phase. It borders pants-on-head-retarded to go through the rigamarole to set up the distribution, and maitenence for an at home system.
I work in a lab, and we ln2 cool our equipment. We have two types of systems, one is a kind of infrared detector that we cool to liquid nitrogen temperatures, a typical fill will last about 14 hours, takes about 1-2 liters of ln2, and it does not matter if the tank gets ice in it, nor does it matter to the detector if it warms up.
There are other systems, and i suspect a ln2daily would work like this due to temp stresses on the processor, where you must keep the system cold at all costs. Such applications are like xray detectors with these crazy berylium detectors... if you warm them up the berylium migrates and the detector must be replaced. Things like this requires quite a bit of money.
In our lab, First we cool our microscopes with Ln2, then we displace the ln2 with liquid helium (4 kelvin baby), It requires huge tanks to be delivered on big trucks, you have to wheel those suckers around. We spend about $40,000 per year on cryogens, and we only have two cryogenic microscopes. Plus, the truck to deliver is coming to the campus anyway, and we have a loading dock to offload the tanks, and elevators to carry them between floors. This would be the minimum setup required for a daily system, unless you went to the trouble to build your own condenser.
Furthermore, every time you dispense lN2 you lose about twice the amount to evaporation as you actually collect in a vacuum dewar. It has to cool the pipes on the way to your dewar, it has to cool the dewar, etc. So you want a big dewar attached to the computer, so that you don't have to refill it three times a day.
Originally Posted by Reflexive
The ability to store liquid nitrogen at room temperature is at thousands of psi of pressure.
While technically true, typically ln2 is not delivered in its liquid state at room temperature. It comes in gigantic metal, low pressure tanks with lots of different gauges all over the side of them. They are held generally at about 2 psi over atmospheric pressure, and make a constant "hiss" as they slowly release ln2. If that gets blocked, there is a backup blowoff valve. It is scary to see a giant tank with 80 gallons of ln2 in it start to pressurize... like... evacuate that part of the building scary.
Even the gigantic ln2 tanks outside sci facilities or at theme parks or such hold thousands of gallons of ln2 at about +20 psi... its just not feasable to store liquid nitrogen at a higher temperature. You can keep it pressurized and let it warm up, but its going to explode.
And kill you.
Now that I think about it tho, if someone wants to do a 4 kelvin suicide run... ive got the equipment here in the lab....
Originally Posted by xapno
Then the dude falls in and freezez but ya
some space movie.
i believe it was one of the nonnery james bond movies. Huge open vats of liquid helium (no) and he falls in and the place explodes (also no)Edited by thiosk - 1/14/09 at 2:44pm