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larger scale ethanol extraction vs BHO. time, cost, and yields

I'm thinking about trying a larger (+5lbs) scale ethanol extraction but a partner of mine keeps trying to convince me that butane is the way to go and the ethanol is way more labor intensive/ expensive and ultimately is less efficient extraction method and we'll be leaving yields on the table.

Our goal is to after we have the oil to fraction later but in regards to extraction our plan is to have all materials sitting over night in a -30 deep freezer and take the dried frozen starting material an extract it in a large vessel which is also in the freezer using 190proof grain alcohol. Then filter inside the freezer using a Buchner and then rotovap distill the alcohol back

My question is;
Is anyone successfully making large scale extraction with ethanol? How are the yields compared to a bho setup of the same size? Is ethanol more labor intensive compared to butane blasting? Our alcohol was not cheap but neither is good grade butane. Is one process substantially cheaper than the other ?
 
U

usually

Sup, the other rules apply for that. You can balance the budget so it looks like you spend the same time/$ using/making both.
 

Gray Wolf

A Posse ad Esse. From Possibility to realization.
Mentor
ICMag Donor
Veteran
I'm thinking about trying a larger (+5lbs) scale ethanol extraction but a partner of mine keeps trying to convince me that butane is the way to go and the ethanol is way more labor intensive/ expensive and ultimately is less efficient extraction method and we'll be leaving yields on the table.

Our goal is to after we have the oil to fraction later but in regards to extraction our plan is to have all materials sitting over night in a -30 deep freezer and take the dried frozen starting material an extract it in a large vessel which is also in the freezer using 190proof grain alcohol. Then filter inside the freezer using a Buchner and then rotovap distill the alcohol back

My question is;
Is anyone successfully making large scale extraction with ethanol? How are the yields compared to a bho setup of the same size? Is ethanol more labor intensive compared to butane blasting? Our alcohol was not cheap but neither is good grade butane. Is one process substantially cheaper than the other ?

Closed loop BHO is typically the lowest cost per gram to extract, but if you are going to fractionally distill it afterwards, you will have to winterize it first, which typically involves alcohol.

Losses of highly taxed alcohol to the plant material, is the biggest cost, so some equipment development capable of reclaiming that, would reduce costs.

We typically extract with LPG, winterize with ethanol, and then fractionate.
 
Thanks GW

You're right I never took into consideration the alcohol loss associated with just saturated plant material. maybe some sort of press can be used. But it starting to sound more labor intensive.

Are you running closed loop LPG? Is the column any different then a closed loop Butane set up? Do you still have to use pharm grade propane if the plan is to winterized, followed by distillation?

In terms of yields? Where does ethanol extraction fall on the chart? Do you typically see alcohol pulling less oil out then the non-polar solvents? Can you pull +90% out on the first extraction? I know it's a fine line between temp and soak time to reduce chlorophyll but the labor goes way up if you need to dry, freeze again and run a second extraction. Any data out the study the temp vs time vS yields?
 

Gray Wolf

A Posse ad Esse. From Possibility to realization.
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ICMag Donor
Veteran
Thanks GW

You're right I never took into consideration the alcohol loss associated with just saturated plant material. maybe some sort of press can be used. But it starting to sound more labor intensive.

A press helps, but can't press it all out, and worse yet, by the time you get the material loaded, a large percent of the alcohol has evaporated to atmosphere.

Are you running closed loop LPG? Is the column any different then a closed loop Butane set up? Do you still have to use pharm grade propane if the plan is to winterized, followed by distillation?

We typically use a mixture of 99.5% Instrument grade butane and propane, which we distill to 99.99 before use.

In terms of yields? Where does ethanol extraction fall on the chart? Do you typically see alcohol pulling less oil out then the non-polar solvents?

If you exclude non target elements picked up through insufficient process control, yield is close to the same.

Polar solvents will pick up the water, chlorophyll, and water solubles, and non polar solvents will strip the plant waxes from the leaves.

Can you pull +90% out on the first extraction? I know it's a fine line between temp and soak time to reduce chlorophyll but the labor goes way up if you need to dry, freeze again and run a second extraction. Any data out the study the temp vs time vS yields?

I typically get most of it with the first pass, after experimenting with the material a bit. The second extract isn't as nice, once the material thaws once.

Another option is to do the first extraction using QWET, and the second using a non polar solvent like butane, which will mostly ignore the chlorophyll.


 

deadkndys

Member
Here's s large scale ethanol extractor. This one processes up to 200 lbs a time.
HItHzlR.jpg
 

PDX Dopesmoker

Active member
I'm thinking about trying a larger (+5lbs) scale ethanol extraction but a partner of mine keeps trying to convince me that butane is the way to go and the ethanol is way more labor intensive/ expensive and ultimately is less efficient extraction method and we'll be leaving yields on the table.

Our goal is to after we have the oil to fraction later but in regards to extraction our plan is to have all materials sitting over night in a -30 deep freezer and take the dried frozen starting material an extract it in a large vessel which is also in the freezer using 190proof grain alcohol. Then filter inside the freezer using a Buchner and then rotovap distill the alcohol back

My question is;
Is anyone successfully making large scale extraction with ethanol? How are the yields compared to a bho setup of the same size? Is ethanol more labor intensive compared to butane blasting? Our alcohol was not cheap but neither is good grade butane. Is one process substantially cheaper than the other ?

I don't know of anyone who does that on a large scale, I do it pretty much exactly like you described other than the large volume & the Buchner. I get about 15%-20% back on good flower, but mainly I use it for taking the remaining goods off of stuff that I've already dry sifted, get about 10%-15%. The points of loss seem to be alcohol that sticks in the flower (1g-2g of everclear per gram of material) and the coffee filter takes a fat dab for itself too. I press out my soaked material in a french press so I'm left with this puck of everclear soaked flower & as the alcohol evaporates it wicks to the top of the puck, leaving all of the cannabinoids you missed in the top layer as you can see in the picture, which is a cross section of the leftover puck.
pYURIYw.jpg
 

SkyHighLer

Got me a stone bad Mana
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Veteran
I don't know of anyone who does that on a large scale, I do it pretty much exactly like you described other than the large volume & the Buchner. I get about 15%-20% back on good flower, but mainly I use it for taking the remaining goods off of stuff that I've already dry sifted, get about 10%-15%. The points of loss seem to be alcohol that sticks in the flower (1g-2g of everclear per gram of material) and the coffee filter takes a fat dab for itself too. I press out my soaked material in a french press so I'm left with this puck of everclear soaked flower & as the alcohol evaporates it wicks to the top of the puck, leaving all of the cannabinoids you missed in the top layer as you can see in the picture, which is a cross section of the leftover puck.
View Image

It recently occurred to me a centrifugal fruit/vegetable juicer, specifically the Acme 6001 would provide far superior separation than a Buchner, or French press squeeze.

Here's the posts where I presented my idea:

https://www.icmag.com/ic/showpost.php?p=7630232&postcount=143

https://www.icmag.com/ic/showpost.php?p=7631360&postcount=144

https://www.icmag.com/ic/showpost.php?p=7631393&postcount=146

In this last one I delve into using it for the actual extraction, I didn't mention it, but you could also extract using butane with it, or use multiple solvents, one after another to get deeper broader cuts, no stopping to dry the material between solvents, nice huh?
https://www.icmag.com/ic/showpost.php?p=7631545&postcount=147
 
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Sky higher you just presented some great ideas. My first thought is to be nervous about the solvent sparking in the appliance. I hope there's a safe way to do that, it's surprisingly cheap. Next time I have some wet plant matter after filtering through my Buchner as usual.. I'm gonna toss it in a non-electric (manual) salad spinner and see if more everclear spins out. Neat concept.
 

SkyHighLer

Got me a stone bad Mana
ICMag Donor
Veteran
^ There's only the power switch to spark, spark less, cool running induction motor. Tape the switch in the on position, or go inside and completely bypass it.
 
It would be really interesting to see what happened if you put, say a half pound of dry trim in the centrifuge and added 1 cup of everclear.

I'd be very interested to see if a full cup spins out. That would be amazing for dialling in a quick wash and recovering alcohol.
 
I don't know of anyone who does that on a large scale, I do it pretty much exactly like you described other than the large volume & the Buchner. I get about 15%-20% back on good flower, but mainly I use it for taking the remaining goods off of stuff that I've already dry sifted, get about 10%-15%. The points of loss seem to be alcohol that sticks in the flower (1g-2g of everclear per gram of material) and the coffee filter takes a fat dab for itself too. I press out my soaked material in a french press so I'm left with this puck of everclear soaked flower & as the alcohol evaporates it wicks to the top of the puck, leaving all of the cannabinoids you missed in the top layer as you can see in the picture, which is a cross section of the leftover puck.
View Image



Yeah I lost about 2 gallons of 190proof grain alcohol running 10lbs of trim but we didn't have a press. Expensive mistake to make. need to find a better method, I like your French press idea. Do you have any idea on the total alcohol loss % even after you press it out...
 

SkyHighLer

Got me a stone bad Mana
ICMag Donor
Veteran
Trick out a washing machine as the extractor, rinse cycle even 'squirts' for you...

Lot of 'tricks' though, sparking electrical switches to cover down (newer machines should have way fewer, but still you'd need to be meticulous.) And the integrity of the plumbing, do the hose's leach, etc. I suppose you would place a filter (fine mesh SS screen) around the inside of the drum.

If you actually ran it like a a washing machine you could divert the wash/rinse cycle drains to different containers. A quick 'Pre-Wash Cycle' with icy ethanol (preferably no agitation - straight to spin rinse,) and then longer and more fervent washes with warmer and warmer alcohol, diabolical.
 
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PDX Dopesmoker

Active member
Yeah I lost about 2 gallons of 190proof grain alcohol running 10lbs of trim but we didn't have a press. Expensive mistake to make. need to find a better method, I like your French press idea. Do you have any idea on the total alcohol loss % even after you press it out...

Its not really a fixed % of the solvent that you lose, the amount lost would be a function of how much material was soaked & to some extent how long it was soaked & at what temperature. Your 2gallons/10lbs is in the same range as the 1-2g of solvent per g of material I mentioned so maybe you had something better than a french press or maybe the french press would perform better scaled up to your scale from mine. I'm pretty certain that my 7 square foot deep freeze would be challenged to hold 10lbs of trim & the french press I use is only about 1 liter.
Also other people's weirder ideas might be even better, I had never heard of salad spinner tek until this thread, sounds potentially awesome.
 
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