Rising film for decarb?

If you’re using a falling film for solvent recovery, why can’t you use a rising film to decarb immediately after that?

You can control the residence time and the heat applied. If you want, you should be able to adjust your decarb based on the flow rates and how hot you crank up the jacket, to make sure you’re getting every last mg out of it, but without just cooking the shit out of it forever to make sure it’s done.

You could just decarb it in your falling film, but then you’re eating into your solvent recovery system’s capacity.

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I don’t know much about a rising film evaporator, but it seems like it works like a thermosiphon where the expansion of the liquid is what pushes it up the column (correct me if I’m wrong). If it is pumped, cannabis oil, even at high temperature is fairly thick and dense, meaning you’d need a little bit of heft to that pump, making for a more costly piece of machinery. But would this only work if the coefficient of expansion for cannabis oil is similar for something like ethanol or water? My experience with the oil is that it does not have expansion properties in that same vein. Maybe someone else could speak to this better than I.

Short residence time and continuous process both seem like wins to me

@Photon_noir?

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couldn’t you just find a way to do it in a wfe? Maybe not scrape as close to the glass to increase residence time? Done at relatively high vacuum for wfe to protect against degradation?

That’s what I was thinking. Cooked up the idea with someone who should know what they’re talking about, they said it was a good one.

I could, yes. But a WFE is expensive. A rising film is cheap, and has fewer moving parts, and thus less maintenance and total lifetime cost. And I can keep my wipers running happily making distillate instead, and making more money.

I could also do it on hotplates in beakers, but when we’re talking 40-80L/hr that starts to get a bit ridiculous.

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You’re close. In this case it would be the CO2 generated by the decarb process that would be providing the motive force pushing the liquid along.

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Might still be too complicated…why not run a Horizontal pool heat exchanger and a peristaltic pump?

Edit: CO2 up. Got it!!

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Not a terrible idea, but the rising film gives us way more tunablity… and while I’m not entirely certain what the regulator may have to say about pool heat exchangers in a GMP process, but I doubt it’s complimentary.

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Raising film is more efficient then a falling

Yeah that makes sense. Would be a cool thing to try.

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horizontal agitated film evaporators are a viable option, could try scraped surface heat exchangers, but may need modification to create a vapor body to handle the vapor load.

My big question concerns the temps for a continuous decarb, know the reaction is energy dependent and we will run HOT but at what speed and what are the caveats? I’d imagine if theres alot of sugars and other foulants in the feed that could pose some issue for both rising film and agitated thin film/scraped surfaceHEX.
I think both Rising film has enough potential to trial on a small scale and check it out, way cheaper R/D that could have a huge impact

Edit to clarify

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We’re thinking a single digit minute residence time along with a reasonable but not extreme heat level should be good.

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I’d be concerned that even 120-130c for less than an hour isn’t going to get the job done. If it’s a continuous feed your resulting oil isn’t going to be at a decarb temperature for nearly long enough.

Though I suppose if it’s in a thin enough film you could get the time down considerably?

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Horizontal heat exchanger with a breather on the return bell maybe?

Not to mention if youre decarbing that fast the expansion of CO2 will mess with your vacuum on the FFE part

Youd need 2 seperate zones with seperate vacuums

Meh. We don’t need to lower the boiling point for decarb, so no strict need for vac.

A CO2 atmosphere should be oxygen free enough to not wreck the cadabinoids.

Makes sense to suck on it. Doesn’t need to do more that keep up with CO2 generation.

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He said immediately after which is why I was talking about vacuum

@cyclopath

Any oxygen in there when you’re trying to decarb that fast and hot will cause degradation, pressure and high temps can cause isomerization to d8 so running under vacuum is definely a good idea.

Shit you could even terpene strip if you set it up right

Agreed.

I saw sequential rather than fusing the devices quite that intimately (still stuck in batch mode).

Terp strip can happen a little further up stream once you can achieve full suck

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Why not use a rising film for solvent strip then falling film for decarb? This way you have more push from liquid expansion then decarb on the way down? If you use a heated distributor plate to even oil flow on FF residence time might be less of an issue

FFE is not gonna be good for decarb IMO due to the evolution of co2 from thin falling film causing splashing/nucleate like bubbling/boiling (i know decarb isnt technically “boiling” but co2 bubbles will pop, splash and create tube wetting issues which could be an issue in regards to efficiency and fouling of tube surface).

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