see that blue sliver? thats a huge rotary vane vacuum pump and the other thing is a diffusion pump
so yes vacuum. but two pumps.
I figured that out seconds after asking
recognized the sensors on the diffusion pump, and recognized the blue sliver. asked.
remembered what a diffusion pump looked like. and how much suck was going to be required.
Hi All…I’m totally new to this forum, and am already a big fan! I have been doing thin-film distillation for quite some time. My gear has included:
Home-brew (well, glassblower built!) falling film still, based on the design in old Kontes catalogs, but upsized about 3x. Welch duo-seal, air-cooled diffusion pump, mercury-filled tilting McLeod gauge for vac sensing (and got ~25 mTorr). ca 1979.
ca 2016: 2" Pope and ~4" Leybold-Hereaus WF units. Both of these are at least 35 years old. 1" bore vacuum manifolding with Varian M-2 diffusion pump, Alcatel and Savant roughing pumps, vac sensing with Kurt Lesker convection gauges, data logging via LabVIEW. Pretty flexible setup that allowed either still to be high pressure (terp stripping) or low (3-8 mTorr for cannabinoids).
…after which I graduated to these two 4" Popes, mostly doing terpene stripping in front of a ChemTech KDL-6.
…which brings me to my comment regarding vacuum. Earlier in this thread mention was made of turbo pumps vs diffusion pumps. I’ve worked with turbos a fair bit, but only in ‘dry’ systems (mass spectrometers, gas sampling systems), and I really don’t think they work for distillation systems. Mainly because their controllers almost always shut down the turbo if there’s a pressure pulse, which can be relatively small. Then, the controller will not allow a restart until the vanes have come down to a slow speed, then they can rev back up. That would considerably bollocks a distillation! Moreover, servicing or rebuilding these things is a shop visit. I’ve seen turbo pumps in the salvage yard of my previous employer that had failed…the vanes had turned into something that looked like steel wool pitched into a blender! Besides…the things are expensive…
Turbo Pumps vs Diffusion Pumps
700L distillate a month contract
Oh shit…REAL Chemist!
the circa 1979 pics are great. pity @circus_animal took down their toaster oven/rotovap kugelrohr pic… I reckon you would have appreciated it.
Well sheeit. That’s some setup!
Sorry about the duped pictures…don’t know why that happened!
I’m currently running a 6ft pfaudler from 1965. We have re-engineered it 4 times. Basically. I have two super low high precision chillers. one running tertiary condenser. and another running two liquid cooled vapor traps. I have two decently sized alcatel vacuum pumps and a diffusion pump. Honestly I’ve extracted 53kg of cbd dist post Degas in 24hrs.
Actual vs Potential Yield expectations
Numbers game: is your WFE a goer?
beautiful set up
so literally a ton of biomass?
Yes. It gets the job done for sure. Still have some things to dial in as always.
Worked with a stainless CTS KDL-6 for the better part of 2 years.
-Quality Build in USA
-stainless models allow faster wiper speeds and in turn lower viscosity feed stock mixtures
- stainless doesn’t usually end up in a $15k+ “uh oh”
-Jualbo chillers and wiper motor (love these)
-very modular for modification
-Customer Service can be a bit hit or miss, however John Hart is pretty amicable with cannabis. Cannabis has risen sharply from the 15% of their business in prior years
-Not a huge fan of their default cold trap setup. Usually just one trap between turbo/diffusion pumps and roughing pumps
-Very pricey IMO
-Feed pump is an expensive European gear pump that can be damaged easily on metal-metal vacuum exposed surfaces by operator mishandling. Definitely want to keep this pump well maintained and do not let a rookie rebuild one.
I’ve had great success with their products in conjunction with some basic sample prep, however ensure your feed rate and wiper speed is effective for your feed viscosity, and definitely degass and strip high volitals (although that’s true of any WFD really.
Hope this helps.
I agree, I love the Edwards RV28 and their 10iC dry scroll pump. Both do great on their own. I especially like the 10ic for things that have solvent or terps in them, as it is a chemical-duty pump.
We also had some startup grief with our ChemTech. I agree their cold finger leaves a bit to be desired…the feed lines (from the chiller) broke…had them replaced with lines with ball joints, and at a 45° angle from the top of the trap, to lessen the chance of strain. Also had the standard taper replaced with a RotaVis, with the expectation of having the female side modified with a mating Rotavis. With the present design there’s enough pressure from the chiller pump to ‘push’ the feed line joint open and leaking!
Moreover, the main O-ring at the top of the glass body does tend to ‘take a shape’ and potentially leak. I busted the top flange on ours by over-torquing the mounting plate. Good to have spare rings, and replace them at intervals, like every 4 months or so.
I really prefer the glass bodies, as some of our distillates produce gummy/tarry residues, and the visual feedback can avert disasters. But if you’re going with glass…be nice with your local glassblower!
Oh yes I forgot about the o-ring issue we had! But that can happen with any o-ring made of that material no? Overall I really liked the Chemtech we had, if only because it was so easy to use. I feel like I spent a lot of time maintaining the Pope, the chemtech not so much.
No argument. Big price differential, though.
Oh yes, huge price difference. Lots of people like that sparkly clean stainless look! At this point Ive managed too make the pope run as well as the chemtech or VTA with my dosing pump
Oh, the Equipment!
Is that the pump that pushes more into the feed?
what did that cost you?