Running n2 without di on collection?

I want to run n2 on my cls. I have a 6x48 column and 12x28 collection pot that is jacketed. And a dewax column and crc column.
My question is can i run n2 without having my rather large collection on dry ice?
Was thinking if its coming straight out of the dewax column it will be cold enough to vent the n2.
But what if i place the crc between the dewax and collection? Any advice?

I don’t chill my collection. I push it in with n2, the solvent being at dry ice temp, helps cool down the collection as the solvent comes in. My collection stays at 0psi until the n2 gets there.

Screw dry icing the collection

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Even with the crc?

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Yes no need for cold collection with n2
I would recomend prv s on the rig thou

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So to clarify all you do is blast solvent out of dewax through crc into collection and vent? Hmm go figure. Id assume the solvent would warm up since the cls is pretty big.

Well a can Now almost dunk solvent treu crc i have half of my crc powder
(B80) at the botom of biomass tube
And the other half on botom of dewax unit i open valves al the way
I dunk 60 liters of solvent like this

I should have clarified that its mounted on a wall. So the column dewax column and crc column are all seperated. Like slabby i would think the sovent would warm up going from the dewax through crc to collection. I just want to be safe haha. I run about 45 lbs of solvent

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Your cold collection is not chilling your crc is it ?

Im confused by the question. We currently run no dry ice on the collection(active)

I plan on running through an injection coil into my column. Then from there route to dewax. From dewax to crc. Crc to collection.

So yes the crc is technically going to be cold but its not being chilled

Exactly you wish to.chill collection to have the least of pressure there correct ?

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I would like to avoid chilling if possible. Im just unsure if the solvent will warm up and create pressure since its not dumping straight into the collection pot from dewax column

A collection pot chilled can create no lower pressure than -29hg or -15psi
So Since cooling your collection does not help cooling your crc
You can yust push solvent treu with N2
Your solvent when cold will be still
Less than -0.8 C when ariving in collection most likely and if not the expected max pressure is 2.3bar 38psi
In the collection tank
Pushing with N2 at any pressure above this will make your solvent flow towards the collection pot
Don t know what recovery unit you use
But some don t like high pressure swings so watch out for that Reason i use warm vapor push my unit can handel the swings so i can keep recovering

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Awesome great info. Thanks.
So are you saying i should cool the crc column as well?
Sorry im tired lol.
I have a cmep.
Also using a 40:40:20 blend. Iso n pro

Depends on the speed your solvent comes treu and the cold absorbed by your crc column
I don t care if it warms up it s already dewaxed and the pressure of N2 or warm vapor pushes it towards the collection pot any ways

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Now im confused again. If you dont care that its warming up after/during crc then how are you bleeding the n2 off? Assuming the solvent warmed enough to create even a small amount of psi in the collection pot? Or by it warming up do you mean its warmer then coming out of dewax, but still cold enough to be at 0psi

There is a phisics law called in Dutch the law of comunicating barrels
If the pressure behind the solvent is higher than the pressure before the solvent the solvent will move in the direction of the lower pressure
Untill the barrels can comunicate and reach equilibrium in pressure
Thus as long as your push is higher in pressure than the receiving pressure the solvent will move in the direction you want
Yes butane will boil under pressure at diffrent temps so this gives room for bleeding if nessesary

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Boiling point is saturation temp
1bar = 15psi

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I see the disconnect. I was not concerened about having dry ice on collection for pulling in solvent like running passive. I get the n2 pushes the solvent through the system.
My concern is the solvent warming up in my collection pot before im able to vent the n2 before recovery.

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That’s. Where the trick is
If butane is under pressure at room temp it’s boiling point is
way higher around 20C so the n2 making even more pressure is pushing the butane down in the tank then when bleeding the nitro the butane will start to boil and yes some butane will be lost but far less then the price of dry ice :grin:

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Oh no way?!
So when the butane starts boiling close the bleed valve?
Its that simple? Thanks for the info brother!

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