I do know about the glow plug part. While some hydrocarbon/air mixtures can ignite in the absence of a hot point, the pressures typically needed far exceeds that of the pressure a typical refrigerant recovery pump (I used the oil-less CMEP) can attain.
I agree with you on this, butane extracts makes far better distillate than ethanol extracts.
Debatable. Neither one of these should happen and they are both equally as easy to prevent.
Thank you for reminding me. Haha I need more of both
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haven’t noticed that one. will have to pay more attention…
how many did you get through 
seems like this one might have relevance to the argon vs nitrogen crowd.
https://pubs.acs.org/doi/abs/10.1021/je00058a015
I haven’t made it past the paywall yet, but there does seem to be a difference…
https://sci-hubtw.hkvisa.net/10.1021/je00058a015
edit: past the paywall and still befuddled… oh well. maybe someone with more physical chemistry than myself can give us the take home? Time for me to get to work…
Air in your system….maybe your not pulling a full vac on one of your columns?
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believe it or not! that is the one I read…answer 1.
I thought the pressures were all too high to be relevent here…
but if you note my comment on someone doing an experiment of
mixing/over pressuring butane liquid with N2 at -50 C and letting things come to equilibrium
room temp in a Parr style reactor…thus measuring the absolute pressure the system might obtain. (split tank observation)…only…
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Butane dissolves quite a bit of water but once saturated with water, a heavier aqueous layer will form in the tank.
That layer can be expelled from a recovery cylinder by setting it upside down and opening the gas port of the cylinder.
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There’s a big difference between air and N2 in your closed loop. That 20+% of O2 gives the air a lot of punch and it certainly isn’t inert; it’s an oxidizer. If your closed loop system allows atmosphere in, it ain’t closed. Close it.
Whenever a liquid is stored in a sealed system there needs to be head space in the cylinder to permit enough room for thermal expansion of the liquid without rupturing the container. That head space can be occupied with any vapor and can be pressurized to the extent allowed by the characteristics of the vapor.
C3 & C4 hydrocarbons are filled as liquids. Let’s talk about a blend of butane and propane that has a vapor pressure of exactly100 psig, (lower than 108 if pure propane). As soon as the liquid fill starts, the blend boils and generates vapor at 100 psi. As the cylinder gets filled, the rising liquid compresses the vapor to a higher pressure and it drops back to liquid phase until the pressure of the vapor pushing down reaches the vapor pressure of the liquid pushing up @ 100 psi. Cool, we all get this.
If you add 200 psi nitrogen into the head space in the full cylinder, the vapor phase blend will liquefy to the point where it’s diluted pressure reaches equilibrium with the liquid below. Because the liquid has a 100 psi vapor pressure, the volume of the 200 psi nitrogen in the head space can hold 50% of the solvent, balanced with 50% nitrogen. The % level of the solvent blend in the vapor will increase as the pressure in the head space decreases. When enough liquid is removed to double the volume of the head space, the pressure of the vapor will be halved to 100 psi and the nitrogen will no longer have any effect on the liquid below. The N2 will not push the liquid out of the tank - the 100 psi of the liquid will and the liquid solvent will maintain the head space at 100 psi.
Here’s where the problem with air in the system comes into play. The LEL and UEL if propane in air is 2.1% & 9.5%, respectively. There may well be enough air / atmosphere in the system to get the solvent in the air in the head space within that range. If it does, the vapor in the head space is explosive. All it needs is a source of ignition.
That’s why you need to make sure your systems have no air in them. Even a pinhole leak can bring air into your system. If your system leaks, fix it. Vacuum your system every time it’s open to atmosphere.
While you’re at it, replace those shitty cheap valves that come on refrigerant recovery cylinders because they have cheap rubber gaskets and seals in them and they are not designed to be exposed to flammable solvents.
Be safe out there.
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not sure if this is the thread to be asking but I didn’t want to start a new thread… for those using N2 assist, what is the most pressure you have had to apply (no CRC in the system this run)
I have a clogged up filter somewhere and I want to blow it out without blowing up. I hate to tear down with out a full dump to collections
Please post pics
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just looking to hear what is the most pressure peeps have had to use in pushing through clogs.
I have charged my tank up to 120psi when I got a clog…I don’t like doing it though lol
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I’d be wary of any gasket filters. You can potentially blow out the gasket as well
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I am very aware of that and I do have gasket filters. That is exactly why I am asking what is the max peeps have used. I pressure test the system with N2 at 100psi before ever running but I have never run a N2 assist above 45psi
Problem solved… pushed the psi up to 70 and got a good flow going now. I love this place!!!
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Yeah I start at 30psi and work my way up to between 60-80 (until my desired flow rate is hit) So that doesn’t sound out of the norm tbh
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Can nitrogen, be added to a Butane tank, with the intent of increasing the PSI, in the Butane tank?
This was the closest post I could find to this subject, yes it’s pushing rather than blending, but is in the ballpark. I’m guessing at least one of you, is an expert on the subject.
Thanks in advance.
What other option(s) can you give for what might happen if nitrogen was introduced in this manner?
What is your goal? (Other than more pressure?)
Using this to get cold solvent out of the tank (zero head pressure or even vacuum if you’ve done it right)?!?
Then search on THAT Eg: Question about Nitro Push
If not, and you don’t yet have an answer, tell us more of your goals…
Yes 
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Fed for a day…
…and there is more to using N2 to aid solvent injection that “can I use N2 to increase pressure in a tank”