[Gray Wolf]

Originally Posted by Old Gold

I somehow got away with 1/4 HP, and it offers 35 ft of head while operating at 14.2 PSI. We are able to push it through two 50 ft cooling coils and two jacketed 12"x30" cylinders simultaneously (inlet at the bottom of jackets). For any seriously large application, surely a 1/2 HP or greater would be minimum.

Thanks, I'll take a look at the smaller pumps.

A foot of head is 0.4332 psi (0.0361lbs/in2 X 12") and for the pump to reach that pressure, requires that much back pressure.

Back pressure is a function of flow, so the pressure required will depend on how much liquid is being pumped through what resistance. As the pump size and flow goes up, so does the pressure and horsepower requirements.

[Alister.Frazzle]

As an extractor hoping to change from room-temp to subzero extractions I find this post to be quite useful in my creative process! With dry ice in the solvent tank what extraction temperature do you think would be realistic? And how long would you expect to recirculate alcohol before beginning to pick up polar compounds? Perhaps a cryogenic centrifuge or a filter press of sorts could be implemented in the extraction vessel for maximum solvent recovery.

[GNYC]

most of what you would press out would be a green chlorophyll soup

[Gray Wolf]

Originally Posted by Alister.Frazzle

As an extractor hoping to change from room-temp to subzero extractions I find this post to be quite useful in my creative process! With dry ice in the solvent tank what extraction temperature do you think would be realistic? And how long would you expect to recirculate alcohol before beginning to pick up polar compounds? Perhaps a cryogenic centrifuge or a filter press of sorts could be implemented in the extraction vessel for maximum solvent recovery.

Between -50 & -70C.

5 minutes or so.

A centrifuge would probably work better than pressing it, but the recovered alcohol would be of different quality and should ostensibly be processed separately.

You could also heat the material while pulling a vacuum, and pull off the alcohol as a clean vapor, followed by condensing it back to a liquid.

[mobin]

Originally Posted by Gray Wolf

but the recovered alcohol would be of different quality and should ostensibly be processed separately.

You could also heat the material while pulling a vacuum, and pull off the alcohol as a clean vapor, followed by condensing it back to a liquid.

even under vac i end up with some azeotroping stank on initially recovered alcos.

50-80mmHg/torr at around 55*c, zero visible reflux/vapor trail, and only seeing condensation once in the trap.

[SkyHighLer]

Originally Posted by Gray Wolf

Between -50 & -70C.

5 minutes or so.

A centrifuge would probably work better than pressing it, but the recovered alcohol would be of different quality and should ostensibly be processed separately.

You could also heat the material while pulling a vacuum, and pull off the alcohol as a clean vapor, followed by condensing it back to a liquid.

On the centrifuge idea, how about first spinning up the dry material at high speed to pack it, and then hitting it with with sprays of cold solvent, gradually ramping up the rpm's, and taking factions as you go?

As to vacuuming off solvent, once most of the solvent's gone, transferring heat evenly through the material might be a problem.

[G.O. Joe]

Originally Posted by SkyHighLer

As to vacuuming off solvent, once most of the solvent's gone, transferring heat evenly through the material might be a problem.

Heat the bottom, make the vessel short and fat chemical industry style instead of tall and narrow supersized BHO style. Instead of pressing or centrifuging, then distilling to recover gunkage and ethanol, why not heat the cake left after after vacuum or pressure filtration, condense the solvent, and leave the crap in the cake and the money spent for the sludge dryer and filter press or centrifuge somewhere else? There are already shiny and fully compliant devices along these lines as fancy as you could want. Such extraction can be mostly done in the insulated and cooled slurry mixer for the pressurized filter with heater, cake stirrer and washer, with washing of the cake until satisfied.

[Gray Wolf]

Originally Posted by G.O. Joe

Heat the bottom, make the vessel short and fat chemical industry style instead of tall and narrow supersized BHO style. Instead of pressing or centrifuging, then distilling to recover gunkage and ethanol, why not heat the cake left after after vacuum or pressure filtration, condense the solvent, and leave the crap in the cake and the money spent for the sludge dryer and filter press or centrifuge somewhere else? There are already shiny and fully compliant devices along these lines as fancy as you could want. Such extraction can be mostly done in the insulated and cooled slurry mixer for the pressurized filter with heater, cake stirrer and washer, with washing of the cake until satisfied.

No reason to reinvent the widget!

[G.O. Joe]

What if stirring a slurry, filtering, and washing gives better more even extraction faster than a column, for the cost of a second tank and mixer that would be nice to have.

Unless it has been/is being arranged for OR law to read BHO technique is mandatory? Stirrer blades and jet pumps are safety hazards, improper engineering, and certainly not best practices eh?

If a legit chemical company was extracting pot with SDA, they probably wouldn't try very hard to recover it - the nutsche cake would just be blown through until dry enough for the landfill, as EPA smiles and waves.

[Pastelero]

What do you guys think about the delta separation CUP device?