I would think it would be cheaper because IMO if you’re running a bunch of 1,500$ - 5,000$ pumps it would just amount to the same as running a bunch of chillers and heaters… But honestly I guess it really just matters on preference. I suppose if a company wants to put the money down to run a larger passive system then so be it.
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I chiller for a small larger system is around 20k
Your thinking small scale.
By that i mean a 100lb solvent tank (filled 100lbs)
20k to get a capable reliabe chiller
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Yeah… Okay I see what you mean now. Because if you’re running a bunch of 4×48 columns into a base and have to recover and then do another column dump right after then you’re gonna want to move the solvent quicker and cheaper.
Think a bunch of 6x48 or 8x48s and you got the idea
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Jeez man yeah may as well just get a pump. I’d say passive with chillers is for the 3×48 columns max
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Thats the point where passive gets to be more expensive then active
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Cause I didn’t even factor in the coolant for the chiller, the heating fluid, the delivery of coolant and heating fluid, storage and the cost of running everything. Where as I’m guessing all you gotta worry about with pumps are leaks and the cost of running them
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You still use some dry ice on your coil(injection and recovery)
But you dont have to get anything else cold. Its significantly less dry ice as long as your not using a trs21 lol. But thats small scale.
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That’s not the max at all…
All I’m saying.
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No. 4x48s are easy peasy with chillers. Even a single column 6x48 but prices start going up from there
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The only reason i know this is because the last facilty i worked at i set up their large system.
I wanted to make it passive but the owners said theres no way with the prices of the chillers.
I did tons of research and shopping and couldnt find a price that worked
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Active and passive both require the same heat exchanges per unit solvent. The difference is active dP changes the temp at which solvent will vaporize and condense. The more solvent you can vaporize the faster it can transfer.
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@randy is right and our local gas expert @downtheterphole gave several hints
If pressure is raised treu heat so does the condensation point
60 psi on collection and 30 psi on solvent tank will already create condensation
No need for cryo chillers at those pressures -20C chillers will suffice
With 1" lines and coils or deplegmators
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Yes if you can get cheap di then disregard
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Beautiful!
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@Dred_pirate
is this considered a form of Entropy? As i’m trying to understand thermodynamics with just a brief search passive seems like the way to go so far!!
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Entropy happens inside the system. Which I believe is what’s happening when the solvent expands into a gas, before it starts recondense(sp?) and turning back into a liquid.
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I see ,Right on! It becomes way more fun and interesting when trying to understand what ,why and how everything is working on a molecular level, thus saving time and expenses!! I guess i’m going down right rabbit hole lol
It’s a much faster rabbit hole, I might add
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