I’m curious if anyone out there has ever used liquid nitrogen to chill columns or any sort of diamond miner contraption? We are always trying to figure out more efficient ways ways to get our temps down to -90/-100
Why liquid co2 and not liquid nitrogen? Are most systems not rated for this cold of temps? is it unsafe due to changing from liquid to gas and causing expansion? Can you use a valve to bleed it out? Are there ways to make it safe?
Any insight would be helpful.
need to make sure your gaskets are rated for that low of a temp.
Also make sure u have proper pressure relief valves setup just incase ur liquid nitrogen line gets clogged somehow
Mixing ln2 with methanol makes a -142 C slurry the methanol prevents clogging of lines deu to humidity
Prv s are crucial as a breaker plates
And all oversized
Damn that is icy!!! Have you done this before?
Yes there sa nice wiki page on cooling baths with many options of mixes
Haven’t found them yet but figure they should make gaskets rated at these temps. Have you ever experimented with using Ln2 in a jacket of some sort?
I used to work for a guy who used liquid CO2 to chill. The problems are high CO2 levels, and the CO2 needs to evaporate in order to chill the equipment so unless there is somewhere for it to go you will have it in the work area. It also would form dry ice in the jacket. This destroyed one of the solvent tanks because of excess pressure buildup and I guess the pressure release valves were frozen.
Liquid co2 can only exist under a pressure of around 75 psi reason I dislike it for jackets
Have you known anyone who has used LN2 for their jacket?
Freezing your butane is the main reason because it’s a pain in the ass to thaw it. Also, liquid nitrogen has a much higher vapor pressure than CO2, and while having a PRV could mitigate this, it would be less intrinsically safe because of the higher vapor pressure of nitrogen. PRVs have a habit of freezing even at dry ice temperatures.
Methanol can help like @Roguelab said; you could also use ethanol for -114C (likely colder) to limit the toxicity issue unless you can handle it. Most people don’t go below -80 for extraction because the color and wax content is minimal and you have an inert coolant instead of a flammable one, it’s intrinsically safer and it can’t freeze your solvent.
If you’re running propane or isobutane, that’s a different story
Also, at these temps and pressures, having a chiller ends up making less sense because everything freezes so it would be easier to just have the jacket of the column be the evaporator of the chiller instead because trying to pump lN2 alcohol slurry seems like a nightmare.
No I haven’t. All the Liquid nitrogen I used was in a tank with racks with handles sticking out of the tank. There are chillers for sale on Future4200 that get pretty cold and should be good enough.
Besides the dangers of working with a liquid with a temperature of almost -200C, the non-evident oxygen depletion in the air within an enclosed room a major concern.
Liquid N2is available in portable dewars that allow for liquid and vapor phase withdrawal. Pressure relief valves on the liquid units actuate at 22 psi. A new dewar with a good vacuum will have a boil-off of almost 3 liquid liters per day, worse or a lot worse for older units or units that have lost their vacuum.
The 3ish liters of boil off generate 75ish SCF of nitrogen gas per day. A 10 * 10 * 10 room has 1,000 SCF of air, which is generally considered to be 78% nitrogen and 21% oxygen. After a weekend sitting in the room venting, the air in the room would no longer be 78% N2 / 21% O2, rather is would be at 81% N2 / 18% O2. After a 3 day holiday weekend, even worse. OSHA preaches that O2 should be at least 19.5% to be breathable without causing problems.
Nobody wants to hear the thud of a body hitting the floor of a C1D1 room.
The danger of oxygen displacement and asphyxiation is another good one, barring if you have crazy high air exchanges (even then). Nitrogen not only mixed easier with air since nitrogen is most of it, and its also easier to asphyxiate on since you can’t feel it.
Many of us have taken a deep breath just above a bin full of dry ice, and that shit hurts. You’re nerves tell you when you have too much CO2 in your lungs not N2.
the response 
We go down to temps of -80 right now and don’t deal with butane freezing but would imagine the LN2 might have that effect.
I used to run LN2 on my material columns for years, I just had my output lines rigged up to the exhaust fan so it would all circulate outside, Like mentioned only issue was the potential of going too cold and LN2 loss can be a little high.
I was stupid one time and took a bong rip with dry ice in it.
I bugged out for about two hours thinking I was gonna die.
I personally have not, haven’t found a gasket rated for this yet.
Gylon gylon gylon… -268 to +260°C
We have various sizes on our website.
He spits hot fire 
