New Pot Huffing on Cool Down

Simple pot still distillation and construction with or without a thumper.

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eternalfrost
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New Pot Huffing on Cool Down

Post by eternalfrost » Thu Apr 30, 2009 5:58 pm

I just finished my first alcohol run on a new potstill i made. it was a stripping run and went fine. the new libig was able to knock down all 5500W into a nice even stream.

but when i shut down the power i noticed a "chug-a-chug-a" noise near the output when i was cleaning up the jars. nothing loud but easily noticable when your heads close. putting my hand in front of it there is a pretty sizable poof of air coming out on each "chug". sounds like its sucking in and out, about 2 times a second.

im not too worried about it as the run itself went flawlessly just wondering whats going on as ive never heard of this and this it the first time ive run a legitimate pot still not a detuned column

Dnderhead
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Re: New Pot Huffing on Cool Down

Post by Dnderhead » Thu Apr 30, 2009 6:03 pm

Cooling and creating a partial vacuum?

Hack
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Re: New Pot Huffing on Cool Down

Post by Hack » Thu Apr 30, 2009 9:53 pm

I'll bet you're getting a vacuum like Dnderhead said. On my setup with a thumper I need to crack the seal on the column immediately after killing the heat or the vacuum will siphon the juice from the thumper back into the boiler.

Hawke
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Re: New Pot Huffing on Cool Down

Post by Hawke » Fri May 01, 2009 3:54 am

I think, if I was to add a thumper, I'd also add a ball valve somewhere on the pot or riser to break the vacuum. Not fond of slip joints and flour paste anymore, so my parts are easy to break down, just not quick to do.
It is the very things that we think we know, that keep us from learning what we should know.
Valved Reflux, 3"x54" Bok 'mini', 2 liebig based pots and the 'Blockhead' 60K btu propane heat

eternalfrost
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Re: New Pot Huffing on Cool Down

Post by eternalfrost » Fri May 01, 2009 6:01 am

I know its a vacuum effect...

im just wondering whats causing the oscillations. because its just a simple keg to 2" reduced to 1/2" to a liebig, all open.

because its fairly intense, about like if you purse your lips and hyperventilate haha

rad14701
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Re: New Pot Huffing on Cool Down

Post by rad14701 » Fri May 01, 2009 6:16 am

Was your liebig drained when this happened or was there still water in the jacket...??? Also, was the rig positioned to where it could get hit by drafts of cool air...???

eternalfrost
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Re: New Pot Huffing on Cool Down

Post by eternalfrost » Fri May 01, 2009 9:52 am

rad14701 wrote:Was your liebig drained when this happened or was there still water in the jacket...??? Also, was the rig positioned to where it could get hit by drafts of cool air...???
there was still water in the liebig shell but not flowing. no air drafts.

FarSideStill
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Re: New Pot Huffing on Cool Down

Post by FarSideStill » Fri May 01, 2009 2:22 pm

pot is cooling, air rushes in to fill vacuum.
new cool air in pot heats up, expands, and blows out.
That's the best i've got...

punkin
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Re: New Pot Huffing on Cool Down

Post by punkin » Fri May 01, 2009 2:26 pm

You could either open the refill port or leave the water running till the vapour stops flowing ...5-10mins...

eternalfrost
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Re: New Pot Huffing on Cool Down

Post by eternalfrost » Fri May 01, 2009 2:28 pm

its not causing any problems just an interesting and unexpected behavior.

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