Hello All,
Looking for some advice on the KDT-6 SP parameters. I have experience with the VTA but none on the KDT-6. I am running the following parameters on CO2 Resin that was stripped of terpenes.
Evap: 160c
Residue: 100c
Feed: 100c
CT: -30c
Condenser: 74c
Vac: 0.0619TORR
Feed: 150 RPM
Wiper: 400 RPM
I am getting a slow drop of darker coloured distillate. The raffinate side fills up pretty quick so I know My temperatures arent efficient.
Any suggestions? Thanks!
0.0619torr is pretty poor vacuum for a WFE system of that size, what are you using for a vacuum chain and have you looked for leaks?
Also 160c should be totally sufficient on a KDT-6 for evap
Edit: For reference I usually get WFE units of that size down to about 0.0003torr or lower when running distillations at similar parameters
You can also run your wipers a little faster than that for some extra residence time, just make sure your basket is trued up nice and straight so you dont put added force on the evaporator body.
We arent using the turbo pumps. It’s for a large operation and I have to turn it a fool proof way for people with no background. I know… not my decision.
Then buy a bypass kit from chemtech and make turning the turbo on foolproof.
If the feedstock is stripped of volatiles then what’s the fear over using the turbo? Does your employer understand they’re shooting themselves in the foot?
I would tell you to have them switch it out for a diffusion pump since the pumps dont usually get destroyed just the oil, but I’ve seen enough people bleed air into them piping hot (even with training) to know that diffusion pump oil replacement is costly on it’s own.
Feel free to tell whoever made that decision that someone with years of experience in various chemtec units is telling you that without a booster pump they’ve decided to own a 6 figure paper weight. In my experience it takes 3-6 weeks of shaadow/1 on 1 training to get someone with no experience to be able to run a chemtec WFE of that size, they’re beautifully simple to operate. You do not need to be a trained chemist or engineer to operate one of these, just dont literally hire someone brain dead with no work ethic.
Make sure the feedstock is stripped of light volatiles & decarboxylated, use LN2 in your cold trap system, and use the booster and you should have very few issues, if they hire someone who can screw it up from there then they need to rethink their qualifications for lab staff…
Looking at your vacuum level you’ll likely need a bigger pump and to crank the evap up, what is on it now? I believe CTS usually rigs KDT6/KDL6 with a leybold D8B.
But, even if you get it to work properly that way your throughput (L/hr) will suffer as well and you might as well just use a couple SPDs. Im very serious when I tell you that under the same parameters you’re running you can do excellent distillations if they just use the fucking booster pump they paid for and the engineers who designed the thing told them to use.
Sorry for the agro response, I’ve had plenty of experience with higher ups making absolutely asinine decisions that makes 0 sense and it gives me PTSD.
Late reply! I ended up pushing them to use the turbo and we have flow. I also had to fight with them to winterize the damn crude to increase potency. We are pushing about 80% THC without doing a terpene pass on crude that is between 60-70%. Distillate is a nice light yellow and clarity is beautiful. How many passes do you usually run before calling it a day and what’s your ratio or raffinate to distillate? We are doing about 3 cannabinoid passes of the raffinate before exhausting that run. The next problem I had to face with management was giving the operators a stopping point. They don’t understand its run dependant so I told them to take the potency of the crude and multiply it by the weight and stop when they reach that amount in distillate. I know they’re leaving a ton of target cannabinoids behind in doing this, but my hands are tied once again. Do you mind sharing your parameters and technique so I can compare? I plan on revisiting a terpene strip, but when I first trialed one, there was no large difference between performing a strip vs not. The management team decided they rather not waste the time on one. What is your throughput rate, potencies before and after and yield?
If you did a terpene pass you should be able to 85%+ potencies, some runs surpassing 90%. You are likely close to hitting your potency cap without a terpene cut. All those terps are going somewhere (hopefully, in this case, your distillate or cold traps), however I’ve found that the KD cold trap systems are not the most efficient in the world. All this to say, you don’t want to damage your turbo or any pump for that matter with all those terps. I’d do an oil change on the Turbo and make sure it is not too terpy before you continue to run as you described. Also, make sure there aren’t any terps building up and potentially damaging your main roughing pump.
If the terpene amount in your oil is non-existent, and your pumps are completely fine, then there may be benefits to not doing a terp cut. While you will be limited with potency, you will have more heavy terps in the distillate. Which may be appealing for certain products that want a more complex terpene-distillate profile.
I developed the SOP and helped run/train folks on a dual-stage KDT-6 at my old job. Feel free to DM me with questions and I’ll do my best to help.
IMO the terpene/heads pass is much more valuable to protect your downstream pumps than it is as a potency/efficiency optimizing step (although it does have that added benefit). Having light compounds in your crude during a main run will manifest in two ways:
Both of these can lead to serious problems with your turbo pump, aside from also negatively affecting the quality of your distillation. I can understand the value of time savings when you’re just getting a less pure product or lower yields, but how much time would you have to save to make it worth replacing/repairing your turbo and whatever downtime is associated with that?
So my CT is efficient at catching the terpenes, some are definitely getting into the distillate. I check the vacuum catch regularly and have very little if any oil recovered. I requested them to schedule me time on optimization early January where I will re-visit the terpene cut. On final pass our vacuum gets down to 0.0006Torr with use of turbo pump. I have been tasked to create consistent distillate but what my management team doesn’t realise is that the output will be as consistent as the input material provided (nothing biological will be consistent). I am hoping playing with some new process parameters and the terpene cut will help me achieve as much consistency as possible but its doubtful.
Vacuum is pretty stable, we get down to 0.0006Torr on final pass with feed speed at 200RPM. Our cold trap is set to -30c and as long as the 50/50 glycol water solution doesn’t get diluted, it maintains temp with no fluctuation.
This is also the problems I face. As their extraction isolation technologist (scientist more like it), I have to find middle ground for quality vs throughput. I obviously want the highest purest quality I can make, but operations want the product out the door as fast and consistent as possible. Its a constant battle lol.
Out of curiosity, what does 200RPM translate to in terms of L/hr of feed? Our pumps were adjusted based on Hz instead of RPM and I don’t remember what Hz we used but I do remember our feed rate during main body runs was about 1-1.5 L/hr.
The rule of thumb for production environments is that the quality just has to be “good enough”. In your case I think a much more important parameter to look at would be the distillation efficiency of your runs. In other words, how many cannabinoids are you putting in vs how much are getting out in your distillate?
For example:
2kg of Crude at 60% potency = 1.2kg of THC
yields
1kg of Distillate at 80% potency = 0.8kg of THC
0.8kg Output divided by 1.2kg Input = ~66% Efficiency
If your higher ups are really focused on throughput and don’t seem all that interested in high potency distillate (I assume this is all going into some kinds of finished products, so they don’t care), this efficiency number might be more compelling to them. However, optimizing efficiency requires nailing down minimum quality standards on their end.
feel free to dm me for an sop
Just throw it up here in the thread that way you can share it with everyone, and be able to help others that haven’t posted a request yet. Just saying…
KDT6 is a great machine! We’ve got the 90i turbo, and just ordered the LN2 insert. I love stainless and once you use it - you probably won’t go back to glass.
Getting great results with the parameters already listed here, give or take a few degrees based on my vacuum depth and feedstock.
On second pass I am achieving <2e-03 on average with turbo engaged. Not the deepest but I’ll take it. I’m sure after a rebuild it’ll be humming. Keeping wipe speed in check and column appropriately saturated, while not flinging solids - I want to push my process faster.
With the feed gearbox @ 25-28 (dart controller) on my 1st pass, wiping at 440, I am only getting about 1L per hour. Evap 170-180, condenser 100. Excellent separation, color, and ratio. Raffinate production is firm and dark. 2nd pass is marginally faster. I know it’s capable of more.
Any hotter on evap and I run into discoloration issues with the current feedstock I am running. Any faster on wipe and I fling solids into my distillate stream during first pass. We do not have discharge pumps, so dumping said discoloration back into feed flask during a run is not an option.
I am hoping the LN2 / deeper vac will allow me to run faster. If anyone could speak to this who has the insert, I would be grateful.