70/30 n-butane/propane VS. 50/50 n-butane/propane. Pressure LIMITS

Using 70%n-butane/30%propane.
150 psi rated loop
What’s the most propane I can mix with the n-butane?!

Is 50/50 to much?

My method I’m using now is-
Solvent tank in dry ice isopropyl bath (cold cold cold)
Chilled column with live flash frozen material (the good stuff lol😎)
Using nitrogen to push the butane into column
30 minute soak
Run more butane through
Nitrogen push in column/tank/honeypot have been maintained to 60psi on gauges. The nitrogen is burped out do solvent tank and honeypot to prevent the gas from getting between the honeypot and solvent tank particularly (during recovery). Solvent tank gets burped also to prevent pressure/mixing after running more butane following soak.
Getting rad results, but maybe a little more propane could continue consistent results. Maybe more propane could even improve quality even more?

Bumping for interest

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We have made blends of 80% propane, 10% Nbut and 10% Isobut. I’ve found that many “chefs” in the industry experiment with different formulas to achieve their targeted output.

Good idea to always burp out the nitrogen. Nitrogen will dissolve in the liquids and create problems as it bubbles out through the whole system. We never use nitrogen at our gas plant - we transfer with liquid pumps or by heating the donor cylinder to raise the vapor pressure of the hydrocarbon for batter transfer to the target cylinder.

Years ago I had a customer who kept a constant pressure of 150 psi nitrogen in his pure Nbut tank to push the liquid phase gas through his distribution system for introduction to his processing equipment. Just like beer that has CO2/N2 gas blend dissolved into it, the gases will bubble out if the flow is disturbed by angles in the distribution line or if it experiences temperature variances along the line.

Regards, Jim


This all depends om your temp.

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Bump. My friend gave me a free tank of 50/50 and im a little concerened about the pressure as well as ive never ran this high mix of propane before…

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I run all propane and rarely see over 100-110 psi, no dry ice mon chilled tank only using regular ice to recover. I also dont use nitrogen sonif you do or plan on it just be careful.

i mean i was considering running N but the pressure had me concerned. appreaciate the input ill pressure test my machine prerun with nitrogen at 150 to make sure its solid. appreciate the quick input. 100psi isnt bad though im hoping for nothing more than 90psi with this mix.

Just make sure all your clamps are high pressure and 6” or less, i let my big collection get to 125 so i can push through crc, biggest clamp is 4” on the end of the 24” bfe. Once your use to it, its not as intimidating. That said if running blends you will recover the propane first so your pressure will be higher at the beginning vs mid way to the end. Not sure on the size of your set up but i use to add even a lil propane back in the day to run crude for vapor pushes etc. They all have there plus’s and minuses just depends on your experience and product being made. Iso is like the middle of the road, ill never run straight ntane again, way to slow

I was thinking about getting an 8"x48" material column. Bad idea?

Hope you like spending an arm and a leg on screened gaskets, lol.

I don’t mind that, I was just curious from a safety standpoint