Pulsating stream on LP pot still

LP, NG, gas burners of all types. Wood, coal or Steam equipment.

Moderator: Site Moderator

Post Reply
1965 wite
Swill Maker
Posts: 253
Joined: Tue Feb 11, 2014 10:52 am

Pulsating stream on LP pot still

Post by 1965 wite » Mon Sep 29, 2014 6:11 pm

So I'm running a full size keg, 2" 3' long column, 3' long Liebig condenser, and propane for heat. I've built a box around the burner to keep the wind from blowing on the flame. I'm getting a pulsing flow no matter what I do. The heat is as consistent as I can get it. Wondering if this is just how propane heat is. Will electric heat produce a more consistent output flow? I've read here and there that you want a consistent flow of 2-4 drops per second for spirit runs. Can a pulsing flow affect the flavor or affect the cut process?

goose eye
Master Distiller
Posts: 2799
Joined: Wed Oct 25, 2006 3:19 am

Re: Pulsating stream on LP pot still

Post by goose eye » Mon Sep 29, 2014 6:18 pm

Suckin air. Worm aint right. Shock coolin.I'd be checkin for leaks
it don't matter the heat

So I'm tole

Andy Capp
Swill Maker
Posts: 337
Joined: Fri Mar 23, 2012 10:32 pm
Location: Australia's rude bit

Re: Pulsating stream on LP pot still

Post by Andy Capp » Mon Sep 29, 2014 7:46 pm

I've had this happen when my liebig didn't have enough fall. Needs at least 45` angle so the spirit can fall away quickly without being pushed by incoming vapor. Can also get it from cooling the liebig too much. Needs to feel hot at the top and cool at the bottom with a warm touch halfway.
A hangover is when you open your eyes in the morning and wish you hadn't.

User avatar
Tokoroa_Shiner
Distiller
Posts: 1321
Joined: Mon Jan 06, 2014 3:02 am

Re: Pulsating stream on LP pot still

Post by Tokoroa_Shiner » Tue Sep 30, 2014 12:14 am

Pot still output should be more then drops per second. Crank the heat up till its a small pencil lead sized stream.
Must read topics for new members

The Rules By Which We Live By
Safety And Related Issues
New Distillers Reading Lounge

Have Fun, Keep Safe and Shine On

BentJar
Site Donor
Site Donor
Posts: 419
Joined: Sat Jan 12, 2013 8:54 am
Location: Carolina,s

Re: Pulsating stream on LP pot still

Post by BentJar » Tue Sep 30, 2014 12:42 am

Take pictures of your rig and we can help you nail that puppy. As stated, more output might correct the pulse. Fast drips to small stream for potstill.
OLD MAN IN THE SHED

User avatar
still_stirrin
Master Distiller
Posts: 8003
Joined: Tue Mar 18, 2014 7:01 am
Location: where the buffalo roam, and the deer & antelope play

Re: Pulsating stream on LP pot still

Post by still_stirrin » Tue Sep 30, 2014 4:36 am

1965,
Is this the strip or the spirit run?

2 to 4 drops / second is for a reflux spirit. Your strip should be faster (pencil stream). You can turn up the heat. And like suggested, make sure you have a gradient on your condenser water temperature.

Finally, with a 2" diameter x 36" long column, you could insulate it to keep the heat in it as the vapor rises. There may be some reflux happening while you're trying to run it as a potstill. That isn't causing the pulsing, but could be slowing your take off speed.

ss
Attention new distillers: Cranky's spoon feed info
My LM/VM & Potstill: My build thread
My 5-grain Bourbon recipe: Special K

rad14701
Master Distiller
Posts: 20866
Joined: Wed Dec 19, 2007 4:46 pm
Location: New York, USA

Re: Pulsating stream on LP pot still

Post by rad14701 » Tue Sep 30, 2014 12:47 pm

still_stirrin wrote:2 to 4 drops / second is for a reflux spirit. Your strip should be faster (pencil stream). You can turn up the heat.
Since when...??? There's no such thing as drips per second for any pot still, whether stripping run or spirit run... Stripping run is as fast as your product condenser can adequately handle... Spirit run is a broken to twisted stream...

Let's not be clouding the issue by giving inaccurate information to novices... Or, another way of putting it, we don't need the blind leading the blind... This has all been covered here in these forums as well as on the parent site so when in doubt, research it to make sure you're doing, or advising, fundamentals correctly... Not pointing any fingers, just stating the facts...

I do see where still_stirrin has mentioned reflux, but that just further clouds the issue here...

Post Reply