I have built and run systems utilizing all the following methods, but I’m curious what most processors are doing. Theoretically the best option would be heater and chiller, but even with a powerful 3-phase chiller it takes my system about 90 minutes to go from hot to cold. I’m currently connected to a heater only and pulling a vacuum on the jacket when passing solvent.
For those running a chiller only or using no jacket, are you running a hot loop to recover some of the solvent, or are you just accepting solvent loss?
It’s been a few years since I extracted with gas, but when I did it, it was an open jacket. After setting up my material column with a filter cake at the end of it and loading it up with flowers, I would vacuum it thoroughly and throw it in the freezer overnight. When I’m ready to extract I will connect my tube to my receiving tank, fill up the jacket with dry ice and alcohol then I would force flood my tube with liquid gas that was appropriately cold with a centrifugal pump and open the valve to my receiving tank. This will give me short residence time and sufficient amount liquid solvent running through the system. After this phase of the extraction process was done I drain the alcohol from the jacket and start running hot water through it to help facilitate evaporation and recuperation of gas trapped in it.
Pulling a vacuum on your jacket is also an option, if the goal is to keep the MatCol cold.
Edit: and I haven’t tried it but I’m curious about shooting hot air thru the jackets when I need to recover, then just pulling back to vac when I need to extract. Seems like a lot less work than pumping liters of liquid thru a column. I’m sure there’s the concern of oxygen in the lab but, if it can be contained to the jacket I don’t see a problem. Wonder what I could use to get the job done?
I did a change up to my BZB columns recently, I used to use Co2 in the jackets but then wanted to reclaim as much tane as I could from the dry runs, so I plumbed in a Tee to the bottom of the jacket port for both hot water from the heater and cold tap water, having this has made a giant difference in recovery
Separate loop for material column jacket with a simple heat exchanger like a power steering cooler from Napa. Drop the pwr steering cooler into your slurry for the cold cold. Then transfer to your reservoir of collection vessel for the heat. This was the best solution for Personel meds shed. Although you should upgrade the plastic output nipple on your pond pump to brass to avoid pumping hot ethanol all over your lab
I understand how to plumb fluid thru my jacket, my point is I want to avoid doing that because I hate dealing with liquid more than I have to, if I can use hot air in the jacket and evacuate it when I need to, it seems like a much simpler heat exchange than passing and draining liquid thru the jacket.
Yeah I could do that but I want to avoid rinsing the material with hot solvent vapor, I’d rather heat the column externally. I could probably just loop nitrogen thru a hot coil and blow thru the jacket, but that’d be a waste of N2.
Anyway, I understand all the conventional methods of recovery. I just wanted to share my thought, I assumed it’d be interesting. If you pass hot air thru your JACKET lmk.
Edit: I also think chilling your material column is pointless. As long as the solvent is sufficiently cold it doesn’t matter.
You can easily just push the liquid and not get the garbage with a manifold. I run continuously so nitro isnt really an option for me and i don’t like it anyway.
Yeah, I had my sleeved column jacketed because I didn’t enjoy having to wait for the material column to be clear of the d.i. before I could start recovering solvent from the column.
I also agree that if your solvent is cold enough and already a liquid in the tank and you’re passing it through the material column anyways as a freezing cold solvent that’s literally pushed from a tank kept on dry ice then I think you don’t need a dewaxing column as your material column.
Though, I still think dewaxing columns as separate columns to further dewax isn’t bad.
I love warm water recovery for the material column afterwards.
TBH, I think that if people got a very small sleeved column and put it on top of their material column that would be probably be a good enough heat exchanger to turn warm solvent into a cold solvent going over your material.
Pumping hot air around the jacket might be dangerous…surrounding the bombs w perfect source for ignition if ever a leak probably not good. The cold alcohol doesn’t ignote6