Thanks that was very helpful !
Only question I have is about this
Wouldn’t this cause there to be remaining solvent in my material column if I don’t push N2 threw it? Thanks again 
Look up Raoult’s Law - the vapor pressure is way higher for N2, therefore it will occupy the headspace mostly
1 Like
I don’t have a real lab . I’m just some one using a little 1 pound cls on my front porch . But I’m trying to get my license for a lab next year so I’m in the process of trying to learn and perfect a system that I can then scale up for my future licensed lab . But I don’t see myself having the capital to pay anyone for professional help even once I get my license . But eventually if I get the money I can definitely see having a professional on staff being a huge help . That’s the goal , but seems like it’s years away at best . I definitely understand where ur coming from tho
1 Like
depends on how you play the rest of the game.
you can certainly get most of the solvent out. either actively or passively. I’d prefer to save pumps for active column recovery only. haven’t had the opportunity to run that way yet.
you can get more out if you heat the columns.
or cool the collection.
if you want to push N2 all the way through to collection, you’re going to have to cool the collection to vent, or recover and then vent. that last option gets dangerous if you add pumps.
2 Likes
Thank you that was a tremendous help
Just because you’ve vented all available n2 pressure from the tank, doesn’t mean you vented all of the n2
N2 is heavy and will sit in your vessels unless a vacuum is pulled
3 Likes
Absolutely true, AND, doesn’t make a huge difference when you’re playing with small volumes of butane in a non-production environment (I’ve played this with high propane blends, and it definitely slows recovery, just not enough that I’d be willing to use a rotary vane on it & the air-Venturi pump never showed 
)
1 Like
Thanks I wasn’t aware of that. How do you pull a vacuum on a tank with butane in it?
Free MIT courses ! This is amazing!
2 Likes
Venturi vacuum
4 Likes
Remember when you showed up and some motherfucker suggested you read?
There is a huge wealth of information here, and it used to be a lot easier to find…
11 Likes
With some common sense and a set of balls…
11 Likes
Their linear algebra and Lie Groups are also worth while.
2 Likes
44North: Do you have a certified Organic Farm?
Curious
I know that the n2 , even though it’s inert, will bond with hydrocarbons and you will vent out hydrocarbons when venting n2.
We switched to argon, more expensive but way more inert.
Don’t know about n2 switching phase of hydrocarbons.
Start at 2:25
Edit: I thought you posted how do I pull a vacuum on a butane tank.
Ummm yeah I’d say a venturi vacuum pump/water based vacuum pump to pull a vacuum on a tank with tane but I don’t see why you’d really need to.
Final edit: watch the video anyways it’s good for knowledge
2 Likes
I’m not sure exactly what you mean about the N2 bonding to the hydrocarbons. That doesn’t make any sense to me but I am open to learn.
1 Like
Follow the 80% rule and use correctly rated pressure vessels (containing PRV’s but even without PRV’s…) and this will never happen. Ever.
There are not many systems on the market that utilize an n2 assist with an operating pressure that high, and again if they are the equipment should be spec’d to avoid the exact situation described.
1 Like