Nitrogen assist dangers?

If your using a basic 2000psi nitrogen tank that regulator will work fine. Just always be sure to keep an eye on it and always close the main valve to the nitrogen tank before stepping away from it. I’ve had a regulator fail and send my tank to 200 psi, scary stuff man. Just add your nitro to the top of your tank, use the pressure to push your solvent into the column then use vapor assist to push it out of the column and into the collection. After you get all your solvent into your collection you can either bleed off the N2 or close the valve between your material column and collection vessel, recover all your solvent and then recover the N2 last. What kind of system are you using now?

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Whoa!! Doesn’t look good to me

We recover through the liquid line of the solvent tank. This way the recovered liquid hits a condensing coil, chilling it before it reaches the tank. On the gas side of the tank we keep a c1d1 air compressor driven vac running to constantly scrub out the head space which is where your nitrogen is building up. This generates a flow going into your solvent tank which eliminates the use for a recovery pump. Just make sure your pressures are higher in the collection pot then in the solvent tank before opening to recovery. With that vacuum running it should create a vacuum in the solvent tank. How cold you can get that solvent tank dictates what solvent you can use without boiling it off from the vacuum. While doing this you need to keep in mind how cold the tank is vs temp that your solvent boils off at vs vacuum pressure. Obviously Butane is going to work best with this if you can’t get your temps that cold. We use isobutane for now but are currently building out upgrades to switch to propane. We rock PRVs everywhere that can be locked down with pressure inside, all manifolds, material columns, solvent tanks, collection pot… Working in 502 in Washington means that if you wanna make changes to your extractor means you have to apply for the change with the LCB, submit your plans to be approved by and engineer. Then after your plans are approved by the engineer you have to schedule an inspection before operating with the changes. Makes upgrading way more expensive having to get that engineer stamp of approval and takes a lot longer having to wait for the approval and the inspection.

The reason I bring that up is that a lot of people seem to think that if something has an engineers stamp of approval that it’s inherently safe which is absolutely wrong. While working in a heavily regulated market like 502 I’ve seen countless examples of dangerous equipment being approved for use by engineers, fire marshals, LCB agents… Its pretty apparent that at this point regulation causes all these hoops to jump through not for the safety of the business but for another way to generate income for the state.

Remember, Safety first… then teamwork.

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Since @Killa12345 appointed me as Saftey Marshal I felt it was important that I comment on this thread. :joy:

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I fucking love it. :heart::heart::heart: @WarrenB

And awesome post :clap::clap::clap:

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Could you tell us what pump you rock on your solvent tank?

Unfortunately I’m about 6 dabs deep and home setting up a pool so I can’t for the life of me remember lol. I’ll text my lab partner and see if he’s sober enough to remember otherwise I’ll get back to you on Monday when I’m at the lab.

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After I drain my material column I always charge it up to 100psi and let it sit for 2 hours to squeeze out any butane soaked into the material Which I have always done this but now reading this post I’m scratching my head wondering if I’m the only person who does this.
I feel it is safe, my 8inch clamps are rated for 350psi I do get my column down to -50 to -80 usually

Anyone wanna challenge me here? Or is this okay lol?

I fucked up bad the other week. Injection was going painfully slow (I don’t charge my tank, I just push the solvent through the column with n2 if my vapor assist doesn’t have enough psi). Well i stupidly accidentally left my injection open and started running n2 into my column. Didn’t see anything happening so I bumped up the n2 pressure. Finally started seeing some dripping into the collection but the psi was way lower than it should have been. Luckily I glanced over at my solvent tank and it was at 175psi. I’ve never had it past 120. The n2 was feeding into the solvent tank through the injection port. Luckily I caught it in time. But I think that’s the closest call I’ve ever had.

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what was your regulator set to? Set it to that of the desired pressure for inject. if your reg is set to 60 psi, your tank wont get over 60 psi.

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So I just got a new system that has 150# prv and gauges everywhere(Dewan, material, collection, tank) and got n2 to try.
Just a quick phone conversation for pointers on how to do it.
I add n2 to solvent tank, run ~6:1 solvent:material then add n2 to push the rest of the solvent thru material.
I generally just add 20-30 psi.
I bleed off the tank and collection to keep shit flowing, and I figured it would be N2 but yesterday I seemed to have lost solvent… shouldn’t the n2 be on the top of solvent vapors?? Or, was some of the pressure released obviously solvent???

a nitrogen push alone is not 100% recovery from material

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when you released gas you released both gasses. your collection needs to be dry ice cold when you burp the n2 after full inject. Anything less and you are loosing gas.

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Dank you, berry much!
problem solved, mostly

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you can also burp from a cold recovery tank and use it as a cold trap, but stall the gas out in the tank momentarily before burping so it has time to liquefy and fall to the bottom.

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I thought these things were a lot stronger like others i am sure

Easy to see why the EGG shape is the safest for pressure vessels

Love this! Been doing it and its so helpful. The stall is clutch. Needle valve is helpful too to throttle… Thanks @Soxhlet, for bringing it up!

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Why would you ever need more than 60-100 psi with nitro? I don’t care how cold you are running… if you can’t get the solvent to move with 60ish PSI there is an issue that pressure will only make worse.

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@The_Lone_Stiller ok it’s Monday, I’m back at the lab with a sunburn after a weekend in the pool. So the manufacturer of our c1d1 air driven vac is Piab.
I have yet to see anyone else use these vacuums in this industry but after using it for about 8 months I highly recommend them! Anyone else run one of these pumps?