Designing multi solvent facility- question on freezers

Hello friends! hoping for a little advice. I am in the process of building our c1d1 extraction room and would like to have a walk in freezer (-40) be used to house the butane, ethanol, and glycol.

Is this feasible? The solvents/coolants will cycle through once an 8 hour shift, with 16 hour cooling time. 100lbs of butane and 50gallons of glycol and ethanol.

Regarding the butane, obviously the tanksnwould need a warming jacket or nitrogen assist in order to flow. I am hoping passive recovery works i hate pumps…

Any adice is appreciated! The pad is poured but everything else is still on paper.

Thanks!!

You’re going to have an easier time implementing some sort of solvent chilling loop/platform with jacketed vessels, heat exchangers and chillers. If you’re suggesting having a C1D1 walk in freezer you’re looking at spending like $100k on something you probably don’t need.

I might be misunderstanding what you’re attempting to do here. Presumably ethanol and butane are extraction solvents but part of separate systems - what exactly are you using this glycol for?

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Was just about to recommend chillers on jackets

Thanks for the reply. The freezer would be a c1d2 space i beleive, as at no point should hazardous gas be present per normal working conditions. our c1d1 workspace is adjacent to the freezer room. The glycol is used to chill a series of rotary evaporators and a short path distillation setup.

my thinking was the walk in freezer could kill several birds 1) provide coolant for roto etc, 2) chill the solvent and 3) provide the heat sink to recover passively.

edit. also the glycol is used to chill thenextraction columns

further edit. our extraction setup is such that we can select between butane or ethanol depending on the client request.

Coolant/heat transfer fluids for rotovaps, chilling jackets, various heat removal operations whatever should just reside within the chiller that is running those operations. No need to carry drums to and from your freezer - the chiller you’ve spec’d for your rotovap for instance should be able to chill its own reservoir down to the set value in a timely manner.

The butane also doesn’t really make sense to store cold. From a hazardous inventory safety standpoint (if this was much larger scale and a greater butane inventory, or liquified ammonia for instance) you might store refrigerated so that your (theoretically much larger) tanks aren’t under pressure because they’re stored below the content’s boiling point. But, in this case its overkill since you’ll be storing small quantities of not-in-use butane as inventory in vessels presumably capable of holding room temperature butane, which must be removed from the freezer and transferred into your hydrocarbon closed loop. Having your butane stored cold presents a problem with your transfer as you mentioned, and once its transferred you will likely have to again confront cooling the solvent further for a good extraction. In this case, you’re better off having a chilled solvent tank or a pre-material column heat exchanger to get your solvent down to temperature before solvent contacts the biomass.

As for storing the ethanol in kegs in the freezer, people do it. Its not elegant, or an effective use of space, electricity, time and ultimately money. Sometimes its necessary if you’ve got a configuration where you need to keep feeding and removing ethanol because you don’t have a true solvent makeup loop reconnecting recovered solvent to feed solvent. So if you’re flipping kegs around rather than (again) using jacketed vessels and heat exchangers (i.e. a solvent chilling platform) then the freezer sort of works. Heat exchange will be shitty since its just cold air and the floor touching the drums. I would suggest getting some sort of ethanol chilling platform like the delta or permacool or pinnacle depending on what fits your scale/budget. If you’re going to end up with a nice walk in freezer either way, use it to store fresh frozen and use more effective tools for chilling fluids.

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You know why you use glycol? Because circulating cold air through your rotovap condenser wouldn’t work near as well.

Even if you plan is to plumb your solvent and glycol in and out of your walk-in freezer, a walking is a terrible way of getting things cold in any sort of reasonable time frame. You also have very little control over your process temperatures with such terrible heat transfer characteristics.

The only reason to set up such a cold room would be to actually operate in it. Which is a game I believe @Roguelab may have played. I’ve certainly spent many hrs in one, but not while playing with volatile solvents or extracting cannabinoids.

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I indeed have but at the same time I could have as much solvent as I please on deck so
The time needed to cool was never in a hurry
To speed up the cooling process I use
Hotwater stainless steel boiler tanks Wich have coils in them and place series of car radiators in front of the fans and a small pump to pump the glycol around from the coils to the radiators and back speeding up the cooling process that is if your cooling power is up to the task

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copy that thanks. im gonna rethink some assumptions as i was planning to plumb everything into and out of the walk in freezer, but the consensus is thats a bad idea…

It is a commonly suggested strategy. Not a particularly good one. Makes some sense if it happens to be lying around already, and is a handy thing to have for storing or prepping biomass.

For chilling solvent, you want an insulated vessel, and good heat transfer via flow over your heat exchanger. For large volumes, that means pumping or stirring. You need to make yourself familiar with some basic concepts around heat exchange. Like how surface area, temperature differential (delta-t), and flow rate affect the process.

Or hire said knowledge…

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I think this kind of approach is only appropriate for small sizes such as the solvent can be stored in a vertical freezer. By the time you need a walk in, it’s better to go with a different approach.

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thanks for the replies. i appreciate the advice you all saved me a ton of money and time.

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Just wanted to say that’s awesome. I’m a single source farmer/solventless processor. I’d love to join a growing team. I have great experience to bring to the table…

can anyone recommend a chiller?something with a 5gal resevoir that can do -40ish? i really dont want to use pumps or have to be buying dry ice.

You should/need to hire a consultant.

But there are a few gems in here.

And a bunch of other chiller threads if you use the search bar.

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