Troubleshooting 3 Stage KDT10

Man, I ran a terp strip yesterday at 158-165C, feed at 10 - 12 Hz, Condenser at 40-45C, Cold Trap at -50C–my terpene fraction seemed to be lighter (in terms of density) than usual. I still had a little blow through to my cold trap of even lighter terpenes when I kicked up the evaporator–I continued to push it back and forth so that the rate of cold trap condensables was low (a drip every few seconds).

Ah, and my vacuum was sitting between 6e-1 and 8e-1 (600 to 800 micron).

I see that your condenser temperature at terp strip is considerably lower.

What is the quality and consistency of the fraction coming off during your strip?

Thanks,
Phil

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This is what a Terpene stripping stage is for. Your wasting time and ALOT of energy by trying to remove volatiles without significant agitation, a vacuum isn’t enough. The KDT units are designed for this express task, and perform it very well & very fast. There is no better option, at an equal cost, for removing volatiles that a WFE in my opinion.

The quality of the terpene fraction is fair to “not bad”. Sometimes even reusable for reintroduction; after a quick short path refinement to separate nasties.
The consistency is liquid with very low viscosity, basically water like. The color is a clear yellow, not gold but bright yellow. The smell depends alot on how it was decarbed, but when vaped the taste is decent.
I found this temperature works best for CBD, although I use very similar methods for THC. My emphasis is to not burn off any desirables in this stage, and I’ve found that 142 - 145C under a 300 - 500 micron vac is the limit before isotope conversion, potency loss, or degradation.

Have you ever had your terpenes tested? It would be interesting to know if there are cannabinoids in there

Interesting, the terps I’m getting vary greatly from batch-to-batch. In some cases they’re lighter in color but more viscous, in other cases they’re darker and less viscous. For the most part, they’re slightly more viscous than water, they’ve got the texture of oil at a minimum.

If it were the case that there were cannabinoids in the terpene fraction, I think it would be minimal–I’m getting about 10% of my crude weight in “terpenes” out of the mixture. If i’m losing even a minimal amount of cannabinoids (primarily THC) then i’m okay with it considering the upsides.

I find that if I go slightly harder on the first pass, the vacuum on the second pass is acceptable.

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My 50L reactor is agitated. I get contamination and poor separation running 40-60L crude batches if I don’t make sure its thoroughly decarbed. Major vac fluxes and an uneven separation of Terps from all the material going through at different vac levels.

And my crude never loses more than a percent or possibly 2 at the very most . That’s cooking a tiny sample for hours. I’d rather have my d9 lower from isomers anyways tbh for one of our clients

Also…ethanol denatured with heptane for extraction, no nitrogen blankets so maybe some water from positive pressure displacements. Recycled alcohol so a lil Terps maybe.

My thinking also includes protecting my pump. If your vac level is bumping, it’s because something is interfering with the vacuum pump. These contaminates can really do some damage over time. I run the low Evap temp for Terp stripping so as not to overwhelm the pump by releasing too much at once for the system to handle. I agree that a good decarb will eliminate most light volatiles, but it’s the heavier ones that really cause issues. I think it’s best to release them in stages rather than all at once. When I run my 3rd pass, my cold trap catches about 5 - 10% of volume as these heavy terps, so they are separated later rather than the first strip.
I should also mention that I am a firm believer in keeping temps as low as possible, always. Heat can be a friend, but too much burns and consuming burnt materials is really not good for health.
I also have a technique for keeping CBD in liquid form using this quick, low temp distillation.

I love it bro we have the same tek

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When you say it “burns” do you have quantitative evidence of this? Or are you just pulling higher levels of oxidized cannabinoids and assuming that it’s because of high temps.

I’m much less afraid of high temps given the extremely short residence time.

You have no idea how much this helped me this morning. Thanks for your insight!

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Happy to help! We are making medicine that goes into peoples bodies, so we all need to make as clean and pure of a product as possible. Feel free to reach out in the future

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I agree that the short residence time in WFE basically eliminates the damage of prolonged heat, but I came from the SPD game first working with all sorts of botanicals and residence time was typically an enemy, so I’m a bit paranoid.
I say “burn” in place of isomerization via heat & oxidation like you say. These isomers react differently and create azeotropes and variations of cannabinoids that I don’t believe have enough research behind them, so I proceed wearily. I have heard of studies investigating liver damage from CBD products, and I have a feeling it might be the consumption of “burnt” CBD molecules (or CBDV, CBC, etc…). I know some processors who go very high with their temps in an attempt to squeeze out every last drop of cannabinoids, and I feel this might be creating harmful compounds.
I know of a few ways to transform terpenes into corrosive or neurological damaging compounds, and it doesn’t require much input. This, in my mind, means the same may be true for cannabinoids but we just aren’t scientifically aware yet.
I can’t provide my own quantitative evidence to back this concern, but I have been qualitatively studying this for a few years with more plants than just cannabis. i.e. If you “burn” a lavender oil extraction, the oil you produced contains compounds that attack the endocrine system if vapor-inhaled or ingested. In medicine making, I believe caution is king.

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do you think of the “mean free path” when approaching your temps
In physics, the mean free path is the average distance travelled by a moving particle (such as an atom, a molecule, a photon) between successive impacts (collisions),[1] which modify its direction or energy or other particle properties.

I operate a mini-5 unit, and the cold trap chiller drops temp the more water dilutes the EtOH bath. Changing the EtOH bath will get the temp down to high -40s, and -50 C. The more pure the EtOH the better.

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