Centrifuge ethanol extraction efficiency

Sorry if this has been addressed, I promise I did use the search bar.

I’m increasingly skeptical of some of the extraction systems offering close to 99% extraction efficiency.

I have a Peony BB-30 centrifuge, it maxes out at 1800 RPM and there is a significant amount of ethanol still in the biomass after the spin is completed. My spin cycle is 12 minutes, 2 minutes at increasing speeds. I’ve weighed the centrifuge bags and the bag weighs up to 8 pounds more after the extraction. This is especially concerning considering everything I’ve extracted has been removed, so there is more than 1.5 gallons of ethanol lost per run, and the cannabinoids retained in the ethanol.

I’ve thought of two possible solutions to minimize this loss. The first is to overclock the motor so that it will go to higher speeds than 1800.

The second is to use some sort of press and to literally squeeze the rest of the ethanol out.

Does anybody have a solution for this issue? I’d rather not mess with the motor controller on the unit and a press seems like it would be low yield and high labor.

Thanks

Modify it to spray in more fresh solvent while it’s spinning once the majority is spun off. Then you’ll replace the saturated solvent with fresh.

You’d only be (likely) losing fresh ethanol, not cannabinoids.

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I have a bit of centrifuge experience though none with Peony units. What is 8 lbs worth of ethanol weight relative to how much biomass you’re fitting in a run?

I’m skeptical whenever anyone claims 99% efficiency on anything, but I feel like 90%+ ethanol removal should be very doable given enough spin time.

What is 2 minutes “at increasing speeds”? Is that ramping up to final spin speed?

I’ve got solid data on only the 10lb (25kg!!) peony unit.

I with 10lb biomass, and 15gal solvent, I was seeing 1 to 1.5lb of solvent retained.

Given a density of 6.8lb/gal, I’m using 102lb of solvent and loosing 1 to 1.5lb

Looks pretty close to 98% to me…

Is that the right way to look at it? Maybe.

Edit: I was seeing less than 1gal retention on 30lb in a 50kg fuge at 1000G. However, I don’t have enough personal run time on those units to give hard numbers.

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HI, have you looked into decanter centrifuges to remove your solvent from the biomass. We have had much success removing most of the solvent from the biomass.

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Go on…

We have had great success with decanter centrifuges extracting solvent from hemp. In a typical process there is approximately 50 % solids to 50% solvent. The model centrifuge used most frequently is capable of processing 10-15 GPM. With a full variable speed machine you are able to control the residence time of the slurry in the decanter allowing you to get your hemp as dry as you would like. Less than 5% solvent in the hemp is easily achievable. Unlike the basket centrifuge a decanter centrifuge does not require any bags or sleeves.

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This is from a test we completed using a decanter centrifuge to extract solvent from biomass.

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Don’t you sell decanter centrifuges?
If so , some data please.
Such as biomass throughput, max solvent recovery per hour,
Percentage residual solvent. That may sell a centrifuge or 3.
Oh and of course cost.

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You could try less weight in the BB-30. Spreading the biomass a little thinner might allow the ethanol on the inner layer to escape more easily. Washing with fresh EtOH would help push out the cannabinoinds but you might not be able to recollect that fresh. I wouldn’t advise overclocking especially if there is a warranty, but you could also try doing a second cycle? When we make RSO in the extraction lab we have a big pot with a ball valve drainage pipe at the bottom. Place a stainless steel rack at the bottom 2-3 inches high and set the biomass on top of that in a mesh bag. Drain every so often and pull off dried material from the top to replace with more saturated herb. Allow gravity to do the work. If you cant get the last bit of ethanol out of that… Back to the BB-30!

Want to get 99+% of your ethanol back?
Use a rotary drier/decarb/ethanol recovery unit like the little one I’m finishing.
Toss in the spent biomass and heat it until the ethanol stops condensing.
Bone dry feedstock and bone dry extracted biomass is what I want for my process.
Rotary vacuum driers are a standard unit operation especially when processing natural feeds.


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Pics of of your decanter or it didn’t happen.

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Post deleted.

@DaKine would love to have that option affordably at the scale I’m at (1200 lbs/day)

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When we use the pandas, we do a 2x spin. The biomass is bone dry when removing from the bubble bags. Spin 1 dine, open bag, hand mix boimass up. spin again.

But still has a wee bit of etoh odor. But is bone dry when grabbing a handfull.

Well, you could start with an old cement mixer, then ………
Why pay a lot of experts to fuck something up when you can do it yourself?

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I’m interested in seeing the decanter fuge as well @CentrifugeGirl

Yes, we do sell decanter centrifuges. There are a variety of different size decanters that we can customize to our clients’ needs. In this particular test we used 14” bowl size. We were able to process around 10-15 GPM of a slurry consisting of 50% solids (hemp) and 50% liquid (solvent). With this decanter you can recover about 350-400 gallons of solvent per hour. With a variable speed decanter, you are able to optimize your process with results of less than 5% residual solvent in your hemp biomass. Again, decanters vary and size and can be larger or smaller depending on our clients needs. Cost also varies depending on how we customize each decanter. Ballpark 75k-100k.

CBD

CBD

Please let me know if you would like any additional information.