very low temperature inlet compressor 1

[nrgy]

I have searched the web to no avail to locate a small
(1 to 2 hp) compressor for compressing nitrogen at -150 C(-240F) with a compression ratio of about 4.
I would appreciate any information on compressor design limitations at very low temperatures.

Thanks for your help

 

[cryotechnic]

With help of Google, I found this supplier... :

http://www.rixindustries.com/

Maybe they can help you.

I was also thinking, do you really need the nitrogen at those low temperatures? If need, it's maybe cheaper to get it heat up in an air cooler and then compress it with a normal compressor instead of one capable for those cryo temperature's.

Or maybe, when possible depending on your Nitrogen source, it's possible to pump liquid nitrogen. Then you only need a centrifugal pump to pump it to the designated pressure and then leed it through a vaporiser. (

http://www.sefco.ch/Start/Index1024.htm)

Let me know what you have found.
Greetings
Cryotechnic

"Math is the ruler of your potential succes...."

 

[nrgy]

Thanks cryotechnic,

I e-mailed Rix . They can provide a compressor to handle only -100F.They did not say anything about specials, or if - 240 F is even possible.

I am trying to design a system with minimal compression work while economizing the liq N2.

I will e-mail a few more suppliers. Sanyo claims a very low temp compressor, but provide no details.

 

[cryotechnic]

So from what I understand in your last post, your source is liquid N2.

Well, if your only use small amounts, I really want to suggest to use a pump to pump the liquid and then vaporize it.
With some control loops (pressure,flow, frequence of the pump) you will be able to control the LIN on a good way.
It's a very commomnly used system.

Another option can be: If you have a LIN-tank from your suplier, ask them what the max operation pressure of the tank is. If you run the tank on a higher pressure (thus, with a higher setting of the pressurise vaporiser) you maybe solve all your problems.
Ofcourse it depends on the pressure you you need in your system.

What is the pressure(barg) and flowrate(Nm3/h) your looking for?

For more info (like tech support), take also a look at

http://www.linde.com

Good Luck,
Cryotechnic


"Math is the ruler of your potential succes...."

 

[Compositepro]

another possibility is to use a heat interchanger and do your compression at room temp. The cold, low-pressure N2 can cool the warm, high-pressure N2 after it has been compressed. You could use an inexpensive chiller to remove the heat of compression.

 

[nrgy]

Here is a simplified description of the system, which should clarify the need for a very low temperature compressor.

The system is for a liqN2 powered engine with vaporization of the liqN2 in an economizer by a secondary gas(N2 or air). The compressor is to pressurize the cooled secondary gas from 1 to 4 atm., thus economizing the liqN2 and using minimal compression work. Flow is about 6 cfm at compressor outlet.


Hope this makes sense

Steve

 

[Compositepro]

It sounds like a form of perpetual motion. Liquid N2 is a very poor source of energy but there could be unusual reasons to use it. But if a compressor is an option why would liquid N2 be used at all?

 

[nrgy]

lqN2 is poor energy source, but about 4 times more storage than electric batteries. See;

http://www.aa.washington.edu/AERP/CRYOCAR/Papers/sae99.pdf