Removing Residual Ethanol


Has anyone tried pulling a vacuum on a primary ethanol extraction vessel with bags of expended hemp to remove residual ethanol vs a centrifuge. eg using a 30 gallon steam jacketed vessel with say 30 pounds of hemp in nylon bags. remove initial ethanol extract, wash the hemp with fresh ethanol, and then pull a vacuum with some heat to dry/remove ethanol from the expended hemp. or conversely add some water and distill out water. i’m looking to put together a closed system that doesn’t involve a centrifuge that can scale up. in large scale vegetable oil extraction plants, you can use steam to strip the solvent but they use hexane which is non miscible with water.


From a purely theoretical physical/thermodynamics perspective, there’s no reason it shouldn’t work at least a bit. Pretty sure you would need to mix/agitate it or something, and I have serious doubts as to if it’s worth doing from an operational efficiency perspective.

Probably easiest to just get a centrifuge but if you’re dead set against spinning things in a circle you could try it. If you do so please report back with results/data.

1 Like

If you pull the remaining ethanol that way, what happens to the cannabinoids in that alcohol?

There are folks in Kansas not getting their cadabinoids, why would you toss 10% of yours out?


It just goes to show you that if we had put a damn wall up on the Kansas border we would not have to take THC out of good and decent American bongs to help their lazy asses! I vote we shut down the DEA until we can get the damn thing up before they start to sneak into America and make more anchor dope babies…
Just saying…

(Ad paid for by Beaker for POTUS dot org. Time for change.)


after the primary extraction, i would remove the ethanol with CBD and run fresh ethanol through the plant material to wash out the remaining cannabinoids. if i use the same volume of ethanol again, it should dilute the remaining cannabinoids left in the plant material from 10 pct to 1 pct. i would use the second wash as starting ethanol for the next batch. any idea how large the centrifuges being used are? i know there are large industrial centrifuges for other industries. i think the CUP 15 holds 10 pounds of plant material. i assume when saturated with ethanol, the weight is about 20 pounds. scaling that system up to handle 100 pounds would be a massively heavy machine to counterbalance the spinning basket. plus u would need a hoist to remove the bag of material and some support for the mesh bag. anyone though of using an ethanol slurry so the material could be pumped? I assume you would end up pulling a ton of chlorophyll but a slurry could be pumped around with a slurry pump in a more continuous process


Getting ~30lb in the BOCK right now.

approx 10% solvent gain over bucket

Not extracting in the fuge (yet).

Have you read the Washing Machine "Salad Spinner" tek thread yet?


Probably. Someone has thought of almost everything at this point in the game :wink:

…they might have been too high to remember that brilliant idea, or too poor to implement it, but there are enough folks looking at this that most of the obvious stuff has been tried at least a couple of times at this point. Imo


thanks for pics. yea i read the salad spinner thread and looked at some of those heartless dryers. those solutions don’t look like they are ready for prime time with large usage