Stretch your condenser out so the coils don’t touch each other. That will give better heat transfer to the slurry.
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It’s definitely the nitrogen creating pressure in the tank
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I think that is problem more than half the problem but i am also running my gas warm I need to cool that shit down, and purge my nitrogen more completely and ill be smashing thru it.
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If you have half inch recovery lines with at least 3kw of heat energy you should be recovering like 1lb a minute, at least 1/2lb per minute. You might consider adding a small solvent tank vapor draw off vessel as mentioned by @Saucyslabz if you aren’t going to cool your solvent tank any further. I’ll actually be looking into something similar but vacuuming down the jackets instead of running them with ice water and using a draw off tank on dry ice.
If I remember right BHOGart uses a recycling line of sorts from their solvent tank(not cooled) back to their evaporation ‘tower’ which then gets sent back through the coil and into the tank again as liquid or something.
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Thank you to everyone who Responded to this thread I’ve got a few good leads on how to accomplish the recovery faster.
The Cold Loop! I’ve been running a Bhogart for years now I love it. It works very well on my 5lb system. But still that will only work assuming that I’ve purged off all the residual Nitrogen in the solvent tank.
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What happens to a normal submersible pond pump when you pull a dry ice/iso slurry into it? Will it fail or seize up?
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There’s a way to do that, but not with dry ice in the solution.
You can use an eco 633 pump. And have that move a cold solution. Externally chilled by a dry ice/alcohol slurry
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Place the pump in a large boiling pot, fill with alcohol of choice (no heptane or hexane or acetone) and let pump fill whatever jacket you need to fill. Return line, back into the pot. Have pot already (makes it waaay easier) in a large cooler. Now fill cooler with dry ice slurry. Put a lid on the pot so you don’t get dry ice in there. And you can get sub -50c if you have everything insulated and keep it going.
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Switch to acetone for your recovery tank.
I imagine that the slurry would work best going thru the pump if its a has more iso then dry ice. Would you agree with that? Or will that pump handle little chucks of ice?
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More likely to use iso 99% or denatured alcohol even im sure it cheaper. Also id like to no have that gnarley acetone smell in my immediate environment
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Don’t send the slurry through the pump. It’s a magnetic impeller driven motor. The cold alcohol is just fine. The dry ice is not. I’ve done this plenty of times and broken the pumps too. Jus sayin
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Understood. Thanks again im gonna search my local hydroshops or amazon it if nothing else
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Amazon has em for sure. They make larger models too.
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21$/gallon if you bought a bunch of 6oz containers from the dollar tree if there’s one near you. But I get it for the smell, it is pungent and not so great to be around
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Update: Ive been over purging on the nitrogen after filling my collection pot so maybe im losing butane vapor faster but im removing more nitrogen,
Also I’ve bumped up the iso ratio in my condenser to have more of a slurry rather than mainly dry ice.
Just doing those two things improved the speed of recovery. On the next run im gonna take @Dred_pirate up on his advice and drop the fuckin tank temp down to well below the boiling point and if that goes well ill have tripled my starting recovery rates 
May the blessing of zeus shower upon you fine folks
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Because the goal here would be to just use the isoalcohol for sending it thru a jacket, Would freezing down the isoalcohol in like a stainless 5 gallon bucket and filter the dry ice using a 190 micron bubble bag and pouring the freezing isoalcohol into a different bucket or use an igloo cooler with a spout and use the spout to pour out freezing cold isoalcohol to be pumped work easier and cause less damage to a pump? Would a magnetic driven fish tank pump with a stainless housing help maintain the cool more?
put the dry ice in the bubble bag, the pump and dry ice can be in the same bucket.
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