Quite a few companies
I’ve spent alot of money experimenting with a ton of different membranes, shits not cheap
can you show us pics of the end product?
I’m more referring to butane and propane in-line, I know there are some that can handle heptane, but kinda defeats the purpose anytime you have to switch solvent systems during production.
This same membrane works with butane or propane.
Butane and propane are even smaller then heptane in size so it would run faster through the membrane also
Youll get a true dewax with a membrane which no one can do by cold crashing in a hydrocarbon, there’s no need for 2 solvents
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which one told you its suitable for butane? evonik?
These are not Evonik membranes
Once you get into membranes with gasses you are better off with
Solid membranes made from minerals and polymers than the evonik types wich are basicly a cloth
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What VFD are you using for your corken? I picked a T91 up yesterday and need to pick out a VFD before I wire this bad boy up.
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SO lowering ph will allow for shatter easier?
Yes but we do this by passing treu acid activated clays not tirtrating with acid drops
Makes sense I’ll try the b81 supreme
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Can you further explain how “it is fairly evident the gas leaving a collection pot is above its boiling point”? Have you measured this?
Unless you have a secondary heat exchanger setup to specifically add superheat to the vapor I don’t think it occurs.
Is the steam leaving a pot of boiling water superheated? No, not even if the hot plate is set well above the BP. It won’t happen unless there is a secondary heat exchanger setup to specifically add superheat to the steam.
I don’t think there is any real argument to be made that very much, if any, superheating would take place in our collection pots unless the pot was setup in a very inefficient way and even then it would be hard to imagine.
The variables you have listed are important to heat transfer rate but not necessarily superheating.
For a given collection pot that is operating at a boiling point determined by it’s pressure/temp curve any heat exchanger surface in contact with the liquid will transfer heat as latent heat which will convert liquid at the BP into vapor at the same temperature.
It happens like this even if the heat exchanger surface temp is much higher (within reason) than the current BP of the liquid. All that will happen with higher temps is heat will transfer more rapidly, more vapor will be generated and the liquid will be boiled off faster, but it will still boil off at the temperature indicated by the pressure/temp curve. That’s how latent heat works.
Think about what happens if you boil water on the stove with the burner on high versus medium. Boiling on high can result in violent bubbling and boil over from all the vapor being generated. Boiling on medium is much calmer with less bubbling and less vapor being generated per unit time. Both boiling situations will have occurred at the exact same temperature for both the liquid and vapor, which is whatever the BP for water is at your particular elevation but the situation with a higher delta T resulted in much more vapor generation and much faster overall boil off of the water.
What I am suggesting is to run your collection pot on “high” when it’s full and/or dilution rate is high (lots of solvent) and then turn it to low/medium to finish. Just like the pot of water on the stove, it will all happen at the same temp, just different vapor generation rates.
Now let’s say you’re operating an inefficient collection pot that’s tall and skinny with a jacket as the only means of heat exchange.
As the liquid level drops during recovery there will be an increasing amount of “heat exchanger” (jacketed vessel walls) in contact with the vapor as opposed to the liquid. This amount of exposed surface area could, in theory, contribute to superheating of the vapor if the heat exchanger temp is up high enough (would need to be REALLY high) past the boiling point.
I really don’t think any real superheating would happen in the above scenario because the overall heat exchange (contact time) that happens as the vapor is rushing out of the vessel is not efficient enough to impart any real superheat into it, even at the modest over-temperatures we’re talking about (I use up to 120F, 50C with propane).
Furthermore, if a minuscule amount of superheating did occur in the above scenario it wouldn’t really matter because it would only be a fraction of a degree and the extract is in the liquid fraction which is always at the indicated boiling point and wouldn’t be effected by any superheat.
This touches on my other opinion that tall, skinny, jacketed vessels are generally not very good collection pots and internal exchangers on wider pots are the way to go for larger volumes of solvent. If you had a vessel with an internal coil placed down low where it’s in contact with liquid for most of the time and then you turn down the heat when the liquid level approaches the exchanger, the chances for superheating would be pretty much zero IMO.
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I’m using an AC Lenze VFD. I emailed Marshall Wolf Automation and they set me up.
I use a 50ft 1/2" coil in DI slurry. Not sure on recovery rate because it changes so much during a run and is mostly dependent on conditions in the collection pot.
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So, it’s quite simple. If you have a collection vessel that is closed—the liquid heats until it reaches its boiling point.
After the phase change occurs, any additional residence time in the chamber is additional time for the gas to pick up heat from the walls of the collection vessel, which are heated above its boiling point.
Additionally if it’s travelling through a molecular sieve and a pump it will also be heated beyond its boiling point.
Pretty standard, straight forward thermo.
Edit: Molecular Sieve Heat = Heat of Adsorption
Pump Heat = Heat of Compression.
There’s no question superheating occurs in closed loop systems—the amount of superheating May be negligible for whatever calculations/design work you’re doing, but ignoring it totally from a theoretical standpoint will snowball into larger inaccuracies at larger scale.
Just something I’ve picked up from other industries and design work.
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Should be able to measure these data points and chart ones process on a molier diagram.
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I can officially confirm that the T-91 is quite a beast.
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The term “superheated” is very misleading…
So pretty much any time you boil or compress gas it becomes superheated (to a variable extent) as it exits the liquid phase or compressor outlet it is in a non-condenseable state; ie cannot return to a liquid until some of the excess heat is first removed. If it were in a condensable state, you would withdraw liquid or a liquid-vapor mixture from the outlets.
With compressors, the amount of superheat is determined by the inlet pressure to outlet pressure differential. The lower the inlet and higher the outlet the more heat will be gained from the action. Take a quick look at a fugacity chart, it will tell you everything you could ever want to know.
During recovery, equilibrium in a tank will take place once the tank cools, the excess pressure will condense back into a liquid. From there, you can further lower its internal pressure by continuing to condense the vapor into liquid by decreasing the internal temperature.
Technically, solvent boiling out of a basin is a very mild superheated vapor (dry steam) otherwise it would remain a liquid-vapor mixture (wet steam) as it enters the compressor inlet.
For those who would like to calculate and verify states:
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Dont forget Raoults Law;
“When an ideal mixture of two miscible liquids is heated to boiling, the solution boils at a temperature between the boiling points of each component. If these liquids have very different boiling points , when the mixture starts to boil, the vapor is rich with the molecules of the more volatile component.”
Such as how people distill Limonene in a water:limonene mixture to lower the BP. The BP of a water:limonene mixture can be under 100c!
This has always confused me with regards to our systems and terpene preservation/losses.
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Vapor pressure is what allows for the terpenes to co-distill with the water… this also happens pretty much with all solvents to a varying degree. Some much more so than others.
You can even use steam to distill cannabinoids. As you increase the temperature / pressure, the heavier weight products can then become part of the superheated vapor stream and co-distill out.
Vacuum or nitrogen can also be used to assist in various ways, such as adjusting the overall vapor pressure total or by reducing the overall boiling points thus preserving the volatile terpenes.
Pyrolysis is also a possibility but the requirements are pretty high… 180c under a 10 micron vacuum.
Now under increased pressure, boiling point elevation comes into play… At which point it is a bit of a combined effort between vapor pressure and boiling point elevation/depression that determines the products that are co-distilled.
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