Hey there.
Lovin this forum so far. Just a quick question. I’m hating working with dry ice and am wondering if I could possibly wrap my collection chamber on my passive closed loop system with a coil and run liquid nitrogen through the coil to keep my system cold. Not sure if -300•f is too cold. Looking forward to hearing back.
300 F is way to cold your butane Will freeze up fir sure so Will Any other solvent we work with in this industry
But Yes a coil or solvent bath can be cooled with Ln2 but quiet hard do get a constant Reading for the time frame You Need iT for
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What about as a bath for the recovery tank? Is it too cold for the metal? Would it fatigue the metal? Seems like faster recovery time.
Steel gets stronger the colder it gets
IT Will freeze You butane and clogg all lines at best
All valves Will die at least get a hart attac
Your steel can handel iT
But your gaskets Will suffer
Mabe with cooling coils and high pressure needle valves a certain constant can be made
But i would then recomend working with a -150C Ln2 assist chest freezer and tubbing to connect No hoses
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No, even steel gets more brittle the colder you get. Look up “ductile-brittle transition temperature”…there is just not a very defined of a curve with austenitic steels, making them still fairly useful at such low temperatures.
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I’m 90% sure I’ve seen someone on here that injects liquid nitrogen Into a jacketed column. Of course I can never find the threads when I need to 
Bizzybee has used it instead of liquid co2
I believe they struggled with not freezing the solvent solid
Just use lco2 plenty cold enough, jacketed coil for solvent injection, pipe to collection base if passive, and a heat exchanger after collection vessel for max speeds
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