Ethanol Extraction and Recovery

I’m currently operating 2 20L roto vaps and processing about 30 gallons ethanol in total through these two vaps in a 9-hour shift and getting about 6lbs of crude total from these two vaps. Is this about average or is there more that I can do to improve the distillation process. Thanks

We call the process “Solvent recovery”.
As distinct from cannabinoid distillation.

Because that makes searching more fruitful.

“Ethanol” will also work better around here, or “EtOH”

Have you read about Optimizing your RotoVap

Or Who is king of EToH Recovery?

Rotovaps are not the correct tool….Glass has lousy thermal transfer compared to stainless. You might should explore Ethanol recovery maths if you really want to understand the problem.

Some are Using moonshine still for evaporation

Others are going the [Open Source Design Project] - Falling Film Evaporator route.

Membranes are probably the most correct solution, but you’re not recovering enough solvent to make them economically viable.

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So what is your recovery rate in liters/hr?

math

3.75 x 30 / 9 ==> ~ 6.25liters/hr on each

Maybe you need the New summit research max rotovap 80 LPH!?!?!?

I think we finally got the FFE supporting four 840mm fuges into the 650l/hr range we need in the last month or so. It required tweaking ALL the things we could modify.

Can you list what those things were?

In order to solve this, you need to know them.
I suspect the open source FFE thread will list them all.

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thanks for the information and correct terminology.

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Chances are you’re also using too much solvent.

How much biomass are you running through that 30gal of ethanol.

My math suggests you’re at about a kg/gal. You can get away with lb/liter at -20C

The links above might well get you where you need to be.

There is also a “buy a clue” option available…

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Try Optimizing Processes with Engineering Fundamentals as well

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thanks,

42 lbs of biomass through 30 gal of ethanal.

So less than a kg/gal…

Washed thusly: It washes the cannabis and then it washes the cannabis some more you can get more cannabinoids with less solvent.

If you read through all the threads linked above and would still like help putting the pieces together, hit me up via DM.

No seriously…

That is a different chemical.
More commonly known as Acetaldehyde.

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:sweat_smile::stuck_out_tongue: Well fucking shit

50lb with 15 gal ethanol. At -40C. Without a decent pump.

Halving the solvent used would help no?!?

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how many times do you wash your biomass?

Have you not followed any of the links?

Wash and a rinse…

Have you calculated your extraction efficiency?

The rig pictured above was getting about 85% of available cannabinoids with ~12% TAC feedstock.

With the correct tooling you can manage considerably better

yes, I’ve reviewed the links provided. No, Have not calculated the extraction efficiency and not sure how htis is done.

42lb in 6lb out.
Brain dead “yield” is ~14%

Use potency on both input and output to see what you’re actually achieving… perform Mass Balance on your cannabinoids.

10kg biomass at 10% thc => 1kg of thc in your input.

1kg crude at 75% thc => 1000 x 0.75 = 750g in your output.

What was the efficiency of your cannabinoid recovery, expressed as a percent?

I suggest always using kg/g/mg for you cannabinoids, but given the way units cancel here, it doesn’t actually matter, so long as you use the SAME units for input and output.

Input mass x input potency
————————————— x 100
Output mass x output potency

Edit: and for continuity:

Follow the cannabinoids not the cadabinoids

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Can you describe the difference between your wash process and the wash @Lincoln20XX documents for us?

WHY does it require less solvent?

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Each 20 liter roto should be recovering 5 gallons an hr at proper temp and vacuum

I’m pretty close to that for about 4 hours of running, it tends to slow down as I start getting more crude oil collected in the fask. Thank you

notice anything you think might be worth implementing over in Optimizing your RotoVap ?

Things like prewarming your input, spraying into the evaporator? Emptying the evaporator without removing the flask?

Are your chillers slowing you down?
What could you do about that?