How can I chill ten lbs of biomass in ten minutes? I know many are chilling in a freezer first but i want to go from room temp to frozen very fast. Liquid Nitrogen? What do industrial large scale processes do?
If you have access to sufficient compressed air: freeze seal We used vortex air freeze seals to freeze reactor coolant lines that were 450F+ as an isolation barrier for removing valves on live systems.
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Thanks. I have used these to keep cameras cool and did not think of using them on biomass. Good idea.
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If that’s not practical, you could always try liquid nitrogen baths.
Pour 10gal of cold solvent on it…
The thermal capacity of cannabis is relatively low compared to that of ethanol. At least once you’ve pulled most of the water out of it. On the order 1/2 that of ethanol. (Link below suggests 1.3 to 2 kJ/kg K) compared to Ethanol at 2.57 kJ/kg K. May be lower based on moisture content.
Given that you’re using 6.8lb of ethanol for every lb of biomass, you’ve got at least a 10:1 advantage.
Is it perfect? No
But it seems to work well enough to get the job done.
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My understanding is that it is ideal to chill your biomass prior to soaking in solvent. The idea being the micro layer of solvent that gets warmed by the warm biomass momentarily will pull out chlorophyll and lipids if the biomass is not chilled. I also understand that is how you get around needing to do winterization I read about the big extraction operations doing this for that reason. Am i getting this wrong?
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No. But you may be trying too hard…
Freezing biomass to make size reduction easier is a definite win.
Freezing biomass before hitting it with solvent certainly has some solid theory behind it. However, do it wrong and get a layer of ice around the trichomes, and you’ve reduced your extraction efficiency.
And wrong can simply mean “forgot about it” for a couple of weeks…
How much water is pulled out of the air to coat your biomass in ice when mesh bags are just thrown in a walk in freezer?
Just not work the effort for hemp imo.
May well be worth it for high end thc input.
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I see. By doing it wrong I would think compressed air falls into that category as air has a lot of water in it. I would guess liquid nitrogen would be best because of the speed? What are ways to do it wrong and form ice besides freezing for too long?
Don’t know. Certainly those vortex tubes are a neat trick.
@Lincoln20XX I can haz?!?
Walk in freezers in OR seem quite likely to cause a “frosty coating”, but “too long” has been the primary issue I’ve seen.
Freeze seals use a jacket system, there’s no direct contact between the air and the product being frozen.
Would you get a higher yield if you froze your biomass for an hour prior to extracting? Im assuming it would allow the trichomes to break off easier into the solvent. It was something I was thinking about this morning .
Also with fresh frozen, if I am taking the material and grinding it in vaccum seal bags, than putting it in a micron sock back in the deep freezer for 1-2 days, is this forming a layer of ice around the trichomes and thus not getting as good of a yield?
@Photon_noir had a great post on why you shouldn’t freeze your biomass and how it warms your cryo extract
This is off the top do I could be butchering his own words
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We’ve noticed no difference in yield from prefreezing, however, we did up our concentration of our crude slightly by prefreezing.
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That sounds like me. I should probably be in this discussion.
I’ll talk to those who control the purse strings. We will see. But I like it.
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Never froze my bio mass, never dewaxed, never had problems. This is a small scale version. I’m having a feeling freezing large scale is more of a problem then just not doing it all. I agree what cyclopath said.
With bio mass and dry ice I never go below -40c
Liquid nitrogen is definitely the way to go. Then a -80°C freezer. Then a deep freezer with dry ice. Then a deep freezer(mine stays lower than -30°C). The less total cells you lyse, the less undesirables.
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I think that sounds like something I said, @BrotanicalMatt … I just cannot remember exactly how I came to that conclusion.
Your results could make sense, @Estokha, especially when there is a little too much water in the biomass OH! THAT WAS IT!
Pre-freezing could actually be “hotter” than simply using cracker dry room-temperature biomass, because pre-freezing inevitably draws moisture back into and onto the plant material when it is invariably exposed to normal humidity air!
Water has a higher heat capacity than the cellulosic plant matter, and water from the air is also bringing its airborne heat with it!
Therefore, totally dry biomass may actually have lower thermal energy than pre-frozen & humidity-re-moistened biomass!
Thanks for the refresher, guys! 
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