I’m looking for a solution to a immediate problem which is pumping my winterized crude from the cryogenic freezers through the lenticular filter. I have a pneumatic pump but it only goes to -20 degrees and I need to find one that is rated from -50 degrees to -80 degrees if anyone has any advice that would be amazing.
inert gas pressure?
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That’s a good idea
what gas would you recommend?
That’s my favorite pump! But sometimes slightly impractical…
You’re likely gonna need a sealless centrifugal pump (though I’m sure certain seals could pull it off). Something like these might or at least steer you in the right direction:
Hermetic Pump
Sanwa Pump
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Doing research this looks very promising thank you for the leads.
nitrogen or co2
one can also go to the other end of the hose and suck 
ie vacuum is another safe way of moving -80 ethanol.
I prefer it to using N2 or CO2, primarily because it doesn’t run out if somebody gets distracted and forgets that they were transferring solvent (never happens right?).
I blow on the hose only when transferring into or out of soda kegs. they don’t do vac, and won’t seal without pressure.
I’ve also pressurized soda kegs with N2 and used those as “sure, go ahead and empty it” reservoirs when vac wasn’t practical.
Speaking of going to the other end of the hose…
I just filled this keg using vacuum, and emptied it with pressure, and used the same pump 
Note: Welsh diaphragm vacuum pump being used for positive displacement…
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I second this. transfer via pump suction is viable but might not be great for tall vertical transfers.
The inline filter seems worth sharing too. 710snob parts. Takes a 5 or 1 micron sock filter.
The real pump being tested here is also visible. At the moment I’m not convinced. It does seem to be getting better the colder we get our solvent.
Note the CBD infused theraputic cement
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Do you think a pump is better after in-line filter or between vessel and filter?
The sock filters are better pushed through than pulled through imo. You can get cavitation if the pump is down stream of the filter, especially as it starts to cake.
That said, I have socks upstream of the pumps, to keep the biomass out of the pump gears should a bag break.
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