Consensus on wiped film distillation parameters

So, believe me when I say I’ve read every thread on distillate parameters but I have a specific situation that I would like some input on.
Our unit is a precision CDU, all glass, pulls a great vac (7.5 x 10-4) see photo…

I have 20 liters of mixed distillate that would likely test out at around 80-85% d9, 85-90% total cannabinoids. Naturally I’d like it to be over 90% in all categories.

Do I
A) Go high temp (170 C), and push through fast
B) Go low temp (158 C) , and go a bit slower
C) somewhere in between.

I have been inclined in the past to go the B route but I’m open to recommendations.
I’ve pretty much got one shot at this as we have no in house analytics and for the life of me I haven’t found a suitable carrier solvent for a little TLC for guidance!

thumbnail_IMG_0239

4 Likes

Out of curiosity, was your 20L of starting material ran through this same wiper?

The unfortunate truth is that there isn’t a magic temperature that gets you an ultra-high potency of cannabinoids, especially when you’re already starting with some pretty damn good distillate. High TAC numbers depend a lot more on starting material quality. Unless you’re doing some kind of filtering or LLE to change the material so that there are less impurities that co-distill, I don’t think you’re going to get an appreciable increase in TAC from running it again. EDIT: If you do get a higher TAC, you’re for sure going to lose a bunch of material to lower yield. There’s no free lunch.

Source: Ran a dual-stage KDT-6 and experimented extensively on temperature effects on TAC and yields.

6 Likes

Yup. And I think you’re on the money with that but the boss wants to try so…

1 Like

My 2 cents: If we both agree that running it again isn’t going to accomplish much, run it hot and fast and that way you waste less time on this little experiment :rofl:

But real talk, some of the folks on here getting high 90% TAC disty out of a wiper swear by running hot and fast, so your results might end up being surprising.

5 Likes

Funny, that’s EXACTLY why I posted this! Fast and hot is not my usual MO but I’m leaning in that direction…

Any one else…?

1 Like

Too hot and you’ll spatter the oleo on the condensing coil…

2 Likes

how bout condenser temps? Feed temps?

1 Like

What about running the condenser hotter as well? To push off some of those oils that may condense under normal operating temperatures (condenser normally between 65-85C), but may not condense at say, 120C for the condenser? This may require a wall temperature of 180 or higher but your whole THC fraction should still condense at 120.

2 Likes

My standard runs go like this. This is BHO winterized/decarbed crude.

lights/volatiles run
Feed, 75C
Evap., 150C
Residue 110C
Condensor 20C
Vac. 1.0 X 10-1 torr

Polish, Final run

Feed, 80C
Evap. 162C
Residue. 110
Cond. 70C
Vac. 7.5 X 10-4 torr

Color varies although I’ve learned that color does not necessarily relate to purity.

I love the glass aspect of the unit as I can see the color and flow rate of the residue and adjust accordingly.

These are very close to the parameters in the original SOP’s from Precision

3 Likes

That is quite low-and-slow indeed, especially for a glass wiper (not that there’s anything wrong with that).

I’ve had good results (>90% TAC) running CBD on stainless steel:

Feed: 80C
Evap: 170C
Residue: 120C
Condenser: 90C

IIRC CBD distills a little hotter than THC, but I’m not 100%. Maybe with the heat loss from glass, those temps will put you right in the ballpark.

5 Likes

Bump! I’m going to fire up tomorrow let’s keeps those ideas rolling!

There is no one size fits all here, but would you expect your impurity to be lights (residual terpenes, smell, etc) or heavies (pigments, etc)?
If lights, run the same temp and bump up your internal condenser 10-30 degrees.
If heavies, turn down the evap temp 10-20 degrees and slow your feed accordingly.
Or try doing both. Either approach should improve your color somewhat.

That won’t be a big issue starting with distillate.

1 Like

Well, it’s distillate so lights aren’t an issue, it’s the “unknowns”, the non-cannabinoids, the what-the-fucks?!
I know that some of this came from cleaning a shitload of jars after the product (budder, sugar, terps etc.) were jarred and I’ve always wondered if the residual glue from the stickers that soaked off in EtOH might leave some residue in the final product but, of course, it’s not something that is tested for. I sure wouldn’t want folks to smoke it!
Thanks for your input.

Thanks to all who put in their $.02 !

Here’s what I decided…

I started at:

Feed, 85C
Evap., 160C
Cond. 80C
Residue 120C

I ran 1/2 hr @ a feed rate of just over 1l/hr , and a wiper speed of 450 rpm (maxes out around 600)
Collected 24g residue and 493g Disty (nice color, light amberr, I’ve seen better, want better) 4.6% residue.

Keeping all other parameters the same, I raised the Evap temp to 165C.
Ran for 1/2 hr, collected 17g residue, 511g disty, same color, 3.2% residue.

Well now i figue if I’m going to “clean” this, I’m going to need a higher residue %.

So I dropped the Evap temp to 155C (keep in mind Bp for THC is 157 @ STP )
Ran 1/2 hr and collected 114g residue 408g disty, 21% residue (much nicer color, straw yellow)

I’m shooting for 10% residue so I have raise the temp to 158.25C and fingers crossed!