If it’s going to residue it’s not fractionating anywhere it’s just draining by gravity.
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oh, ok. so what can i do to change that? so im not losing good product
Is your evaporator temp the wall the wipers are wiping against?
yes it is
Seems about 30 degrees too low for that vacuum level.
I have a generic wiper and a vacuum pump in need of an oil change that pulls 40-60 milli torr and my final pass is at 185 evap 100 internal condenser.
ok, thank you. ill try inputting these numbers, run em, and see if that helps.
how fast should i run my feed pump with these settings?
That’s going to vary system by system, but I don’t really change mine from pass to pass. But then again I’m not squeezing liters out every day.
i was just curious. ill just feed like i normally do and make adjustments along the way.
If you want to actually understand what you’re doing during this process I’d encourage you to do some reading on the relationship of boiling point and vacuum, at a bare minimum know the boiling point at the operational pressure of your system.
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ive been trying, but i just cant seem to wrap my head around a pressure-temperature nomograph or how to use it.
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Mechoulam found a bp of 155 at 50 millitorr. Can you trace that green line?
The center crossing point doesn’t change. Find your pressure 60 millitorr on the right. Connect that point through the center point and it should intersect at your bp.
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Bonus points for understanding the statistical nature of the boiling point as a statistical range.
At a substances boiling point more than 50% of the molecules will have enough kinetic energy to break the liquid-liquid surface tension and become vapor. Held at that point for enough time and it will all evaporate. Your wiper has a set, much shorter residency time however, and you want 100% of your target to be able to evaporate, especially on the last run. You are likely going to want to overshoot that bp a bit in practice.
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if it starts out working at those parameters, and then (sometimes) doesn’t.
the issue is likely to be found INSIDE imo.
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with that fancy looking software why doesnt it make those calculations and show in simple terms like a bar from red to green. Germans would do that. It should be simple like setting the parameters and then a guage that reads live and shows red/greeen various pressure/temps and stuff
honestly, i couldnt answer that. i really dont know
are you really just getting that?
does that mean you don’t know what the inside of your wiper physically looks like?!?
you need to solve that.
…and chances are it needs you to see what it looks like in there too.
hopefully the contact @Miles-Beyond shared will get you though this. I’d tend to talk to them first, because although everything @anon64373531 says is on point, the fact that you ARE getting evaporation/distillation early, and then it ceases suggests to me you’ve got something else going on.
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ya, i just recently started working here and its been really busy. but i will make a point to open everything up and do an overhaul.
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