Questions on switching cls from active to passive.

Hi there! I am currently running my cls via active, I want to move away from that. I have my eyes set on switching it to a passive monster. I would like to know what it takes to make a quick recovering machine passively. I’m assuming something like keeping the solvent tank in a strong iso and dry ice mixture, using only 3/8ths hoses on the recovering side and using a coil submerged in dry ice and iso after the collection base. I do have another question, will I have issues keeping the base warm and pushing cold solvent out of the material columns with n2? Thank you I’m advance for any input you share!

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Bump bump

Why would you possibly want to run passive? Don’t you want a fast active recovery?

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I think it’s been proven over and over that passive can yield very fast recovery times, if you’re willing to use large amounts of consumables

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yes, if you dont have a seporate tank to receive the vapor your system will stall, adding more n2 might compound the problem with high pressures/ slow recovery.
Most people will cool the recovery base and boost with n2, chill off the recovery base and burp the n2 before recovery. This keeps the gas/liquid moving tward the cold recovery base.

If you choose to heat the collection pot during injection you will need a chilled second tank to receive the vapor from the process, we use a recovery pump to recover the n2 gas and butane.
From there we run the system in reverse, we use three way valves on the injection. We reuse the same n2 charge all day long. At the end of the day we do a chilldown and burp.

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Wow that’s incredible. I like that.

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We run passivly for 90% of the process, the recovery pump is just used to move everything back to the chilled receiving tank, which then becomes the next “injection” tank and vise versa. by the time your ready to load the next column the chilller is at least -75*c. The flow of coolent is then directed to the next “receiving” tank. The injection tank coolent is left valved off, we complete injection in 12 min or so. The cold receiving side sits at a vacuum and rises to 15 psi after the n2 comes over.

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I was worried about the pressure stalling the recovery maybe if I drain into a chilled base and then with a recovery pump pull the n2 charge from the base into another tank that’d solve the problem. Is that similar to what you are describing?

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I’m not active I’m passive but that’s how I would use a recovery pump, just dumping the butane off into the recovery tank. 'Cause the extraction process itself doesn’t seem like it would need a recovery pump but moving the butane from the base to the tank seems like it would be easier with a pump.

yes, but you wont be able to seporate the n2 and the butane untill you chill the base. That is why we recover the n2 and the butane into the same tank.

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So the nitrogen doesn’t hurt the butane right? Like you could keep and reuse nitrogen-laden butane inside of a recovery tank and it would be okay and you could reuse the butane for another extraction, right? Also would a double.injection port on the top of a cls help the n2 to enter the extractor…well be easier?

As a vapor they will combine together, upon condensation the butane will return to a liquid and the nitro will stay a vapor. Inert gasses won’t change phase as easily

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Is it safe to do an extraction with the recovered butane if it still contains n2?

It won’t have any in it, when it turns back into a liquid the butane separates and they aren’t together anymore. So, yes it is perfectly safe. All of my butane has been a vapor with nitro, turned back into a liquid, reused until its gone.

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wont effect the butaine

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yes, it is preffered!

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Your running the nitro thru your pump? I’ve all ways just used hot vapor to push my system it would have been very hard to push with nitro and the hot vapor empties a column in seconds with no added gas to recover just by simply using the previous columns vapor as soon as the liquid stops I open one of the recovery valve and it basically “puts the brakes on it” and then I isolate just the hot column and it’s recovered to zero in less than a min and on goes the next. I like the way yours sounds definitely one of those systems I’d like to see in person

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Heres a pic of a hybrid passive unit.
The n2 stays in the headspace of the injection tank like a spring to move the liquid, after injection and recovery of 90%of the liquid the recovery pump is turned on to scavange any remaining gas. All is returned to one of the tanks, then re injected with the next column.

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So let me ask you this, would it be a good idea to have a double injection port at the top of an extraction unit, like this.

Like one for butane one for the n2 push