Sciencemadness Discussion Board

What part should i try to remove and keep from a refrigerator that i found in the street?

El_Kod - 12-1-2006 at 18:48

i think the topic says it all....
i can't find the company that made it, but my bet is that it's about 5 years old max, not those from 1900.
i want the freezer cooler to make liquid O2 and liquid N2 :D

thanks for the help. (in advanced..)

Twospoons - 12-1-2006 at 20:39

The entire refrigeration circuit - thats the compressor, JT valve, evaporator, condensor and all the plumbing.

The_Davster - 12-1-2006 at 21:34

Yeah, definatly do what Twospoons suggested. Start with the big compressor at the bottom and remove all tubing, electronics, etc that is attached to it. Just leave a big insulated box.

El_Kod - 13-1-2006 at 12:18

thanks guys

bullstrode - 13-1-2006 at 15:44

There is some info on refrigeration compressors here:

http://www.belljar.net/refrig.htm
http://www.sas.org/E-Bulletin/2003-12-12/labNotesAS/index.ht...

There is also an article on liquifying gases using a compressor on the Amateur Scientist CD released by the Tinkerer's Guild. You might be able to get it through this very slow link (unless you get it directly through I2P):

http://sasquotch.i2p.tin0.de/archive/AmSci01/1969/11/1969-11...

watson.fawkes - 15-2-2011 at 06:02

Quote: Originally posted by El_Kod  
i want the freezer cooler to make liquid O2 and liquid N2 :D
Playing with a refrigeration circuit is definitely a good learning experience, but don't expect to get to liquid air temperatures; they just don't go that cold.

gsd - 15-2-2011 at 07:08

@watson.fawkes

I think that was a tongue-in-cheek comment (a flagged one at that).

It looks like El_Kod is well aware of the fact that working fluids of household refrigerators have solidification points way above the liquification temperature of air.

gsd

Contrabasso - 15-2-2011 at 07:35

Air is liquified by the expansion of compressed AIR after the removal of the CO2 content and the water content.

peach - 17-2-2011 at 22:25

[Topic merge this into the loooooooong fridge pump post?]

Quote: Originally posted by watson.fawkes  
Quote: Originally posted by El_Kod  
i want the freezer cooler to make liquid O2 and liquid N2 :D
Playing with a refrigeration circuit is definitely a good learning experience, but don't expect to get to liquid air temperatures; they just don't go that cold.


Well the freezer as is can't, but the process of liquefying air relies on compression and cooling.

You could squash CO2 enough with the compressor from a fridge and cool it enough in another freezer to drop it below it's critical temperature and turn into liquid CO2; just... I think.

The liquid CO2 will cool through expansion enough to then potentially liquefy N2 provided it's also compressed.

I began wondering about this after chief mentioned it a long time ago. I recall some fun being poked at him because you'd need a cylinder of CO2 or a fire as the source to begin with. But, standing out in the garage, I then realised I already have a continually burning, very efficient CO2 producing, fire in the house already. The combi boiler.

That is a huge amount of effort compared to simply grabbing a tank and a nozzle. And it is far from a safe. But, it does appear to be possible based on the critical temperatures and pressures the pumps can manage.

The gas need not actually liquefy in the pumps, it only needs compressing before hand if the output isn't going to recirculate.

I think that's what they're doing in this video. But I haven't tried any of this (beyond checking the pump pressures), I can't speak German and there aren't many details to begin with, other than it involving five cascade stages.

<iframe sandbox title="YouTube video player" width="480" height="390" src="http://www.youtube.com/embed/GHDZt1r4Ap8" frameborder="0" allowfullscreen></iframe>

[Edited on 18-2-2011 by peach]