Could I push nitro into the headspace of my tank, have the cold liquid butane go through and land in my collection, then open the valve between the collection and my tank to start recovery, then vent from my tank once all of the nitrogen + some of the butane is inside?
I see in the OSS Nitropush vid they vented from the top of the material column but I don’t think it would be a good fit as I’m trying to avoid submerging the collection pot in dry ice for efficiency purposes.
are you running passive or active? I typically vent my nitrogen from the collection pot before I start recovery and it’s still cold. I get slower rates if I let the N2 go back into the recovery tank.
I vent off the recovery port on my collection base prior to recovery for passive. Before addin the line. But I also dont hook up recover lines till I’m ready to recover
Active u can take the nitro charge with the solvent and reuse both ,passive u cant
Are your solvent tank and recovery tank one and the same?
yes they are
i’m running passive,
if you let the n2 get into the recovery tank couldn’t you then vent it from the recovery tank?
You can vent from your solvent tank, yes.
Nitro in solvent tank, fill column, nitro in column(depending on setup) to push through crc, vent isolated solvent tank, recover while collecting, when recovery stalls vent solvent tank again, finish recovery.
Absolutely. Because Nitrogen is generally inert, and it is lighter than butane you are able to evacuate the n2 from your tank easily.
I am assuming you have already bled your recovery tank to 0psi if you are at the recovery stage.
If you care about solvent loss I would recommend opening the collection to recovery, then closing the pathway back off after roughly 5 seconds (system dependent). After that bleed your solvent tank down to the working/recovery pressure your used to seeing.
For even more assurance bleed your tank lower and watch for pressure buildup of your tank. IF you see the pressure rise after you bleed, the n2 is out of your tank
Hope this helps!
yeah definitely, you can vent it from anywhere really. The reason why I vent before starting recovery is to remove any added pressure from the system that can cause recovery to slow down.
If I don’t burp my collection pot, I will be sitting around 50psi in my collection. When I open the recovery port, the pressure equalizes between the pot and recovery tank. From here let’s say the recovery tank is at 40psi. Once you start to recover, you’re fighting against 40psi in your tank which will slow down recovery.
If you vent before recovery, then place your tank in a dry ice slurry, it will pull vac on itself and pull the vapors over much quicker. You don’t really need the N2 for recovery at all, so getting rid of it early on prevents it from causing any problems later down the run.
That’s just how I operate. Everyone has their own preferred way of doing things and there are many ways to skin a cat.
Hey Clouds,
When do you introduce N2 into the system then? Are you able to still run your solvent through coils to chill it?
Get a manifold connecting to different parts of your system so that you and inject where ever you need and vent where ever you need. @bhogart has a sick manifold called the FFP. Its an excellent to to have on a closed loop system
That’s usually why people run n2. To get super cold solvent moving through their coils and system 
Some people induce nitrogen to their solvent tank before pushing fluid so that the solvent pushes first and is then is followed by a nitrogen flush. Some people do it to the top of their column to push the resin and solvent through to collection if they have jacketed columns and are having trouble get the liquid to dump. Its up to you, and depending upon what you are using it for there are several ways to do it.
Think of the nitrogen as a plunger. You push from the top of tank forcing the solvent out of the liquid side into the column. Id imagine that if your full on butane in your solvent/recovery tank, all that nitrogen would stay inside that vessel.
Thanks for the quick reply! Thats what I have seen!
It just seemed inefficient to me that one would inject N2 into the headspace of the solvent tank, only to have to chill all that solvent back down to safely vent the N2. It seems easier to vent it from collection, before recovery since there would be less solvent in the collection than the solvent tank, thus easier to cool, correct?
I was just unaware if there was a way to vent N2 from recovery, that was introduced to a system to quicken solvent flow through coils. Or if the only way to quicken solvent flow through coils was to inject N2 into the headspace.
Sick manifold… that they sell for $500
HFS has the same thing for a fraction of the price
Yeah if the spool is jacketed and has a slurry around it, the solvent tank is chilled and your injecting through a coil in a slurry, Id imagine there are flow issues. In that theoretical set up where would the best place to inject N2 be?
Just vent the nitro outside. Even with room temp solvent, you can do simple math to figure out when your nitro is evacuated. Hell, I go by sound. You can hear the difference of nitro venting vs LPG
Both. I have quick connect fittings on my holding tank and my material tubes, so you can swap as you go. Push solvent into tubes, then flush the tubes.
As long as your not having flow issues or problems actually filling the column with solvent, then simply push the nitro from the top of the material column once you are ready to dump. If you are having flow issues, then nitro push through your solvent tank. This only works if your solvent tank has the amount of solvent you want to run, otherwise you will run the entire tank. You obviously have to push through the vapor line and pull from the liquid line.