Surging Potstill

[libertyesq]

I am running a pot still, about 6 gallon capacity. In my last couple of runs of UJSM, instead of having a nice smooth stream from the condensor, I am getting surges, where it almost spits, followed by streams of output, followed by little to no drips. This pattern repeats every minute or so. Any thoughts on what is happening? I am heating the boiler at a slow rate, not fast. I have four pieces of ceramic from a broken coffee cup in the boiler as boiling chips which have worked well. It appears that pressure may be building up too when it does this, (a serious concern) although there are no obstructions in the worm or the lyne arm. I'd appreciate any advice.

[Hawke]

Sounds like you have an upward slope in the worm somewhere. Distillate is pooling in the low spot until it blocks the worm, then pushes it out.

[libertyesq]

That's something I considered too, that it was being held up somehow, but the slope is downward throughout. I'm baffled.

[Usge]

Hmm...might help if you describe your still a little more too....ie..does it have a column on it. Lots of people call just about anything that doesn't have an internal coil a "pot still".
Number one is make sure your output from condenser is open to the atmosphere. (ie..not buried in liquid or sealed up in anyway)
Could need a good cleaning. You never know. Something could be gunked up somewhere.
A vapor leak can sometimes cause a similar behavior that you describe.
Having your water to condenser hooked up backwards can do something similar too (ie..cold water at top...hot water at bottom).
Could it be your still is puking on your a little? (ie..you are getting foam up that's blocking the top)? Was the pot filled higher than before? etc.,


But, since you seem to be suggesting it just "started" doing this....ie..didn't do it before...the bigger question would be what has changed?

[BW Redneck]

What are you running it on? An electric hotplate cycles on and off and creates surges. If you hadn't already said that you've had more consistent results before this started happening, I would have said that.

[libertyesq]

My still is a rather traditional type pot still, no column, with a lyne arm on top, with about 18 inches of copper tubing running into the worm box condensor. I heat it with propane.

[goose eye]

chek for leaks. aint gotta be much to make it lope. sniff

so im tole

[Usge]

goose is on it....vapor leak. But, it could be too..that your wash is puking (clogging up the head). You getting any discolored distillate?
Sometimes runnin a wash that ain't done....can make a lot of foam.

It sure sounds like something is clogging up something somewhere for some reason. That ain't good.

Besides smelling...look for any tell tale sings of drippage stains on your pot. The other is...to turn off all the lights and use a flash light.
(that's what the fire dept does when they are looking for vapor smoke).

[mbasketcase13]

Sometimes i just sprinkle a little flour on the joints to check for leaks

[Usge]

They say dish soap works good too (ie..bubbles)

[The Chemist]

Try some new boiling chips, also. Don't know any good scientific reason why they should 'go bad'...but I've seen it too many times to say it doesn't happen...

[libertyesq]

Thanx guys,

It looks like I had a small leak in one of my lyne arm joints. I fixed her up and I'm trying her out right now. Hopefully that's it. I also took some of the mash out so it's not so full.

[Usge]

Follow up and post how it goes Liberty. People search out these kinda threads for similar problems...and it will be good information to know what solved it.

[goinbroke2]

My first run with water/vinigar was surging quite a bit, spurting even. The coil had (has) a slight up grade some place. When I ran off a wine concoction it went very smooth until the tails where it started again.

Since it's only mild and there is no real pressure build up I'm going to leave it.

(wow I contributed to a thread speaking from experience!?! How cool is that for a newby???)

[libertyesq]

Sealing up the vapor leak didn't work. I thought for sure that would be it, but still surging. I checked the condensor for any upward slope, but there doesn't appear to be one. Also, when it spurts, the distillate is not discolored at all. Thanks for everything so far, any other suggestions?

[Hawke]

Don't know if it works for a worm, but putting a small bit of copper scrubber in the output end stops surging with a liebeg. (mine almost sounded like a grandfather clock)

[goose eye]

get flashlite an look an see if any solder is is bilt up on botom to stop flow.
put a pitch on the botom of condencer out.
have you put level on condencer out of coolin barel before. depends on how it put together if botom is same as top. ole boys i no when they make one they put 1 inch drop from in to out on botom but keep top level. comes in handy on ruff banks.

so im tole

[Dnderhead]

If I can explain -- Vapors condensed filling the lower part of condenser tube these would normally run out ---BUT new vapor coming into condenser
collapses ( turning to liquid ) causes a vacuum holding liquid in condenser , until still builds up enough presser to expel its content just to repeat
this can be cured in a couple different ways --- have the condenser so it does not fill with distillate - 1) big enough in diameter so it can not fill up
2) just the right lenght so vapors are condensed at very end
3) a" vacuum brake "

[goose eye]

dunder wouldnt you be seein vaper bein pushed out to

so im tole

[Dnderhead]

Goose Depending how hard you are are running the still and how bad the condition is ,as most describe nothing comes out then a "spurt" followed
by a "spit " similar to a kid blowing his juice out of a straw (at his sister?) HE holds juice in the straw ( the vacuum) blows it out (the presser) and if he keeps blowing the "spit"
and I thank that you will fiend this happens more with small diameter tubing ---(compared to the size of the still ) - I thought that Id add
that the old worms was a continual part of the lyne arm witch carried the dstillerant out of the still room out side to the worm witch mite be several
stories high the worm continued to taper from 6-8 " down to two? being taperd it gave the vapor a chance to "collapse" with out creating a vacuum
"