In my circumstance I had tried pushing a crc column that had stopped flowing with 50 Psi. I went to walk my dog and came back to 350 psi. I closed my eyes flinched and opened the valve lol. It wasn’t that crazy of an offgas but my material lid Gauge was maxed out. I’m not sure what happened in there maybe an exothermic reaction with water and alumina heated my nitrogen. IDK all I know is I almost had a heart attack looking at that gauge.
This was nitrogen gas with a regulator. I closed the nitrogen feed before I left
I’d suggest that initially there was a very small headspace (relative to liquid volume) at 50PSI, and that your liquid solvent warmed up in the 30min you were away and made that volume very, very, small.
that would be consistent with
I’m only guessing that your solvent went in cold, and your column was uninsulated…those are requirements for this explanation to work.
I would additionally posit that the CRC in question could theoretically have been filled to 100% with liquid. Which I suspect is a flaw with many implementations.
is 350PSI the appropriate panic point for the bits you’re using?
is your space setup to handle a PRV letting loose?
I like the plumbable PVR’s, you can route them to the exhaust vents, “outside”, or even to an evacuated tank. a manual override is also a nice feature. especially when N2 is in play.
you can see one of those on the dual CRC I’ve posted around here somewhere. The other one was pirated for another project before I got the picture.
So I’ve had this thought experiment a few times @cyclopath and I always thought it was similar to a propane tank in the desert. The propane stays liquid at 100°f because it’s under pressure and at some point the force of the solvent in gas form in the head space applies enough pressure to keep the solvent liquid.
Say you’re running a bottom fill system and a 70 30 n butane/ propane mix. The system is designed to “over flow” into collection at which time the material column could be isolated for a soak. On a scale of 1 to 10 how dangerous is it to implement long soak times without temperature control at the column itself? And assuming the 80% rule for a vessels max fill, doesn’t a “soak time” break this rule?
At 80% fill, you can soak at room temp all day long, provided your system is designed to handle the pressures of said solvent at room temp. The 20% head space is enough to maintain safe pressures.
Which is my point/ question. Trying to run the math on a ~100% full column filled with -30c 70/30 solvent that’s warmed to say 15c, or even just to 0°C. I’ve been wary of practices and dont want to make waves but as an operator I’m 100% certain this is an unsafe practice. Regardless of “counter pressure” that the gas in head space supplies. I expressed said concern and I have been reassured it’s safe by an employee, but said employee also said an MK IV is rated to 1000 psi. Which I also know to be a total crock pot of horse manure… so as a family man with saftey in mind, I want to ensure safe operating procedures.
I understand what you mean now. I personally would never allow solvent at 100% capacity to warm up. You may not experience an exploding vessel; however, your seals will almost definitely begin leaking liquid out of the column.
U left ur nitogen running while u walked ur dog? I only pump mine a few seconds till my pressure is above 30 on my dewaxing columns. Never had a Clog w that method. Even w a crc
But a regulator set at the appropriate psi wouldnt allow the excess 300 psi. I dont have a gauge on my columns, and would never expect these pressures unless one is actively warming a vessel, or supplying unwarranted nitrogen gas… the former which is not uncommon for crc.
I added 50 psi closed valve and waited for the liquid to go through column. Figured Id take the opportunity to let my security squad go potty lol I was wrong
I was not actively heating. Just read what @cyclopath said… It’s like he had something similar happen to him or something. Or maybe he’s a god dang genius… I mean he just won the @beaker award
Are you using an injection coil?
How i do it is after i inject i take the coil out of the slurry and put it in a bucketof warm water. The liquid turns to gas dumping over half of the column. Then you can hot loop
After you’ve added your propane to your column and everything settles into the collection pot. Do you recover the propane? Or burp it off like you would with n2? Since it will boil off first before n tane or iso butane…correct?