I know that Summit Research’s carbon scrub comes with a SOP on the side of the container.
Look at the thread on Cbleach. Has enough info to get started.
Mod Edit: CBleach Scrub and Internal Journal: Future's Pesticide Remediation Tek
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I like Auber. they make a PID controller with a timer function built in.
however, bucket tek requires no temperature controller.
monitoring temps to maintain -45C to -50C is advised.
if above controller could chuck more dry ice in the booze auto-magically, it would be a win.
as far as budget controllers from Auber go. This one is less expensive, but not quite so plug and play.
and then there is the cheap version…
https://www.amazon.com/Lerway-Thermostat-All-Purpose-Temperature-Controller/dp/B07CBQQMDW
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I’m usually a hydrocarbon guy, but I have always been curious about using ethanol for large batches. Since this is the budget ethanol conversation, I wanted to see who has used a moonshine still for recovery? If I remember correctly, @Future mentioned using one back in the day on ig.
Do you have any tips on accomplishing this, or recommendations on a still size or design? Aside from burning the crude, what issues should we be aware of?
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been there, done that. ethanol is way easier to scale. Stills are well developed tek. Rainier knows stills and cannabis.
got a 100gal vac assist still I’m working on spinning up. started at 5 gal and worked my way up.
I guess technically I started with 2" of 1/4" copper tube bent in a U that I picked up and used as a condenser on the vent hole of a rice cooker lid when we were making RSO many moons ago. the proof of concept lasted until the copper exceeded my pain threshold at around 70C and I dropped it 
For a while I had a condenser soldered to a mason jar lid, and could recover solvent at several different scales, from 4oz to 64oz using a rice-cooker as a double boiler.
My current 26 gal still was probably $2500 in parts. All off the shelf except for the boiler and it’s controller. the boiler uses a ~3gal tank salvaged from a commercial chiller…it came with level senders, thermocouple, temp and pressure reliefs etc. Grabbed the SSR’s to drive the heater as well. I threw a 5500 watt water heater element in there, and use a cheap PID controller to keep it just under a boil.
The big one was less than $20k for two 100 jacketed vessels, still head, condenser, vac pump, and air powered agitator. $40k if you add the heater and chiller.
100 gal keeps me under the 120gal Ethanol in a CLS limit in my juristiction. Your mileage may vary.
I suggested the spray-vap, or a falling film rig, but the price of admission was deemed too high.
It was supposed to be installed as part of a hemp processing operation, ON the farm, where I could have reused well water for cooling, and then to water the plants. It was relocated to the city, where we’re going to have to pay for electrickery to cool the condenser rather than throw water down the drain.
Vac assist requires agitation, once I have the big still up I’ll probably try adding agitation to the smaller still as well. Although if I can find an off the shelf 8" product shot-gun for the right price, I might add a recirculation pump & try a DIY falling film.
As far as burning crude goes, I stop early and finish in a rotovap so I can control the product. It’s pretty difficult to burn anything if you’re using hot water to heat. And you should be. you really don’t want direct heat, or any electrickery around your 190.
My 100gal still has a 10" manway at the bottom, to allow the operator to get a spatula in there to move product out the drain hole if they accidentally “finish” in there. This was suggested by the supplier, who was heating their prototype with steam, and had a major problem with removing too much solvent.
The 26 gal one is based on a jacketed conical fermenter, and does a great job of delivering the goods into my 5l rotovap flask when it’s done. 26gal still is driven with 96C water & takes about 12hrs to recover 15gal. Product is fully decarbed at end of run. loading less than 7gal results in a partially decarbed product. Haven’t looked hard at losses to thermal degradation, but have not seen CBN showing up on my 3rd party testing (ask a stranger) or in-house analytics.
With the 100gal version, I’m running vac and aiming at 35C in the boiling vessel, theoretically I can hit 25C if I suck harder. no clue what recovery times are going to be. hoping I can get THCA out of it. would be nice if I could also get decarbed by running at the right vac level.
I was concerned that scaling would lead to long dwell times at temp, but pulling a vac solves that problem. not sure an off the shelf 500gal still is going to take 25in Hg. I did propose it at one point. as a solution to the 500lb of accumulated cannabis in the corner. “I can process that in one day!”. I don’t remember the exact numbers, but it was something in the range of $200k including solvent.
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Thanks for the info here, lots of solid points.
From rice cooker to 100 gal is quite the come up! Between the bucket tek and a DIY still, ethanol is sounding more and more feasible for large batch budget extraction. I’m going to have to research some still plans.
That 26 gallon unit sounds perfect, do you have any pics?
No pictures of the actual unit.
essentially this still head
mounted on one of these
I dislike throwing water down the drain, so I’m using a 50’ ss coil with fans as the condenser these days. Using a couple of 1/4HP hydroponic chillers (craigslist) in parallel wasn’t quite enough cooling to allow recirculation. budget constraints keep me from pursuing that option further.
the still pictured sells for $700. but uses direct heat. you want to go with jacketed or bain marie style heating.
Rainer probably has everything you need.
Yep. EtOH is budget tek for sure. you can even make your own solvent…
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For sure wasn’t recommending the temp controller for the bucket tek lol, I was inquiring if that controller would be an economical option for applications requiring temp control. I appreciate the Amazon recommendation. I grabbed one of these Briskheats off the shelf. Amazon.com
I looked into making my own solvent, and legally, you need a federal permit to do anything. I’m not sure anyone in the cannabis industry would apply for that permit.
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yeah. looking into that too.
was hoping to feed my spent biomass to edible mushrooms, and use the mushrooms to make ethanol.
I put a couple of interns on the problem, and one of them got their sterile technique to the point where they could actually get lions mane growing on post hydrocarbon biomass before we stopped producing it.
Post ethanol biomass was more problematic. I may try again now that my CUP has landed. although I suspect I’ll still need to do something about the last bit of solvent.
You can also apply to the Feds to get the all but 1$/ gal of the “beverage” tax on your extraction solvent back…if you’re up for telling them you’re using it for extraction…I left a link around here somewhere.
mod edit: https://www.ttb.gov/applications/manufacturer_nonbeverage_products_packet.shtml
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Do a butter or cooking oil extraction, cheese cloth is super cheap and will work for straining in a pinch although it does suck up some oil. Then do three or fours water washes in a sep funnel (or mason jar), taste will be vastly improved.
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so I’m not high on glue?
one can use saline washes to clean up a cooking oil based extraction…
I’ve never done brine washes on cooking oil, but I don’t see why not. Several washes with pH 7 water does a good job of deodorizing the cannabutter. You could probably even A/B extract THCA out of cannabutter, provided you managed to not decarb it all. Would probably be difficult to perform a thorough extraction with butter without getting to decarb temps, it could probably be pulled off with canola or similar. Then you’d just need a small amount of solvent for recrystallization!
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Does anyone extract with anhydrous alcohol? It seems easy to remove the water from the azeotrope with a molecular seive, if that pulled over less chlorophyll it would be worth setting up I would think.
You would need to work in an air free manner, etoh will pull moisture from the atmosphere and become well…hydrated. Absolutely you can dry etoh, keeping it that way is hard. Most dry chemistry is performed on a shlenk line, solvents are all freshly distilled and dehydrated.Glassware is dehydrated under vacuum with a heatgun, reagents are kept in a glove box under dry inert gas, chemicals are added through septa or valves. Considering most extract at quite a low temperature with etoh to avoid lipid pickup, I would say most water soluble compounds are locked up.
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Lots of companies are willing sell you 200proof ethanol to perform your extractions. Some will swear it’s better. I picked up some because it was cheaper than the organic 190 I usually use. I made sure it was manufactured in an appropriate manner (last of the water pulled with sieves rather than eg benzene).
I did not split a pile of biomass and run side-by-side extractions.
I did get great results, but I put in high end flowers, and ran at -80C, so I was expecting great results. after recovery, it was at 190 proof (no surprise). Second extraction seemed on par with first, but I made no attempt to actually quantify things like extraction efficiency, color, terpene profile etc.
While both extractions were the same strain, they were different runs, and differences in input would likely have confounded attempts to quantify 200 vs 190…all I can really conclude is that it was not obviously inferior to using 190 proof.
@Photon_noir has stated a couple of times that the azeotrope is almost perfect for our particular extraction (if performed at the correct temp).
My take is that if you don’t have your material & solvent cold enough to lock up the majority of your water solubles, 200 proof will pick them up, along with some water, and be at 190 (or less) moments after it hits your material. It loves water!!
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You are absolutely correct! It loves water, and getting it cold makes water condense into it, driving it to the azeotrope that much faster. My point is that if 200 proof is more expensive (over 5% more expensive), it isn’t worth it, mainly because it goes to azeotrope in no time… and if by some very careful procedures, you did keep it 200 proof, you would pull stuff you do not want (see plot posted by @gratefulhearted (sp?)). Also, just in case, you did right to make sure it was made properly, though they rarely use Benzene anymore because it is toxic to workers.
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Bueller…?
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Can you elaborate on how the thca would crash out? Wouldn’t he just be making hash by washing trim/flower with high ph water? Would the thca crash out of the trichome heads when phd down?