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Reduced Pressure Cornelius Potstill for 1-Pot AG

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Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Mon Jun 10, 2013 10:11 pm

I made a vacuum still mostly because I didn't know any better. I had heard about stills, but never actually seen one. I didn't know anyone who had a still or had ever run one. I did some research. At the time it seemed to me like a lot of research. Most of what I found was what I now recognize as a CM with the coolant lines run through the column, which didn't make a lot of sense to me. I avoided chemistry classes in high school and college, so I didn't know that chemists only use vacuum distillation for substances with very high boiling points. A buddy gave me a Cornelius keg. I didn't have a sufficient heat source readily available, but I knew that boiling points vary with pressure, so I thought I could save a lot of power by running under vacuum. [Of course real distillers knew that you can't change the latent heat of evaporation, so the only savings are in the warm up.] And I really wanted to try to make some absinthe. And after all, if I waited untill I knew everything about our fine hobby to start building, I would still be buying liquor frrom the state. So I started tinkering, and because I didn't know any better, it eventually looked kinda like this, and booze came out.

The purpose of this post is to describe the vacuum potstill that has served me so well for the entire 18 months of my vast distilling career, and maybe spark some interest and discussion. There must be a million configurations that would work better than this. Somebody needs to think 'em up.

I feel obliged to note that there is a large group of home distillers, all intelligent people with much more experience than me, who believe that any form of vacuum distillation is far too dangerous to be practiced at the hobby level. There is another group who think that any use of glass is a certain recipe for disaster. For my part, I try to recognize all the safety issues and take appropriate measures to minimize the risks. It's a hobby for adults only. Just like investing, everyone has to determine their own risk tolerance.

Sorry for the photo quality. I suck at pics.


cap tube.jpg

Looking down at the top of the Corney boiler. Poppets are removed from the pressure ports. The 1/4 inch copper tube is crimped off at the bottom to form a capilary tube to stop bumping. This is essential equipment. On an early run it bumped so hard it would have jumped off the stove except for the safety tie. The tube is flared at the top. It goes in one of the pressure ports, the plug screws down on top of it, and a temperature probe wrapped with PTFE tape goes in the plug hole to seal it. When it starts to bump I loosen the probe. 1/2 inch copper pipe is soldered to the other plug for vapor exit.

The yellow muck in the boiler is all grain bourbon, ready to run. [This is why you might care.] I cook the corn, mash, and ferment in the Corney. After the run I take it out to the garden and rinse it out with a hose. I love it.


stillin 036.jpg

The Corney lid gets flipped over and wrapped with PTFE tape. Vacuum sucks it down to seal. This also makes a safety valve. If the pot should ever pressurize, it is free to pop off.


pot and thumper.jpg

The boiler sits on its original rubber base in a 10 quart stock pot oil bath with a safety wire tied around the "lynn arm." The black band around the middle is 11 ga. steel, soldered full width to the pot, to make sure it stays round. Its predecessor suddenly becamed square one day in the middle of a run at 28+ inHg. It sounded like a 30.06 went off. I no longer suck it down past 27 inHg.

The thumper is a one gallon glass jug with an EPDM stopper. Vapor in is 3/8 copper unrestricted at the bottom. Trying to disperse the vapor caused extra pressure drop.


collection.jpg

A vacuum gauge hangs on the worm bucket. The collection vessel doubles as vacuum trap. The product tube extends a couple of inches into the bottle so the liquid dosen't get sucked into the vacuum port. There is a needle valve after the worm that I close to preserve vacuum while swapping bottles. I have plans for a manifold and isolation valves [a "cow"] to allow changing bottles without interrupting collection. It just hasn't made it to the top of the projects list yet.


asp.jpg

Vacuum aspirator, $35 online, screws onto a garden hose. The black hose is the vacuum supply. It takes about 3 gallons per minute to get maximum suckage. I don't see any reason why it wouldn't work on a recirculating coolant pump. I tryed using a mechanical vacuum pump but I couldn't stand the racket.

I run the rig between 25 and 26.5 inHg. [90-125 torr]. Pressure drop across a thumper is about 1 inHg. depending on the liquid level. At 25 inHg water boils at 135f so there is no problem with condensing at room temps.

There should be a video on YouTube that I made when I was experimenting with multiple thumpers. It would never come up in YouTube search. If I can find it I will post a link.

Thanks for your attention.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Mon Jun 10, 2013 10:44 pm

I suck at videos too.
http://youtu.be/gG4AxBNLv10
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Sun May 04, 2014 7:38 pm

I just cannot believe what I just saw, and read! SKOW!!! I had no idea you were completely BAT SHIT CRAZY! :lol:

Never in a million years would I have thought all of that insanity could come from your mind. I mean this in the best of all ways it can be received. For a fella that just had an urge to make some hootch you managed to create the perfect example of one of those old 1950's propaganda high school films like "Death on the Highway" or Reefer Madness". And one other thing... I have NEVER heard any adult use the phrase "maximum suckage" NEVER! :lol: :lol: :lol: :lol:

Skow, I love the insights, and words of wisdom/kindness you share on the forums but, REALLY? :-o I have to re-examine everyone, and everything I thought I knew. :crying-yellow:

I'm just floored. :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling:

I'm gonna have to revisit the horizontal column concept now :think:

I hope you take this in the good humor I intend it, and I really respect the fact you created that death trap on your own. I give you credit just for surviving it.

I also cant believe no one responded to that post. It's like a car crash. :lol:
I love ya man PLEASE don't be pissed. :bow-blue:

I may need to be "put down" soon.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Tue May 06, 2014 6:38 pm

Hell, Zombie, that's the most complementary response I've ever had.

You must be pretty bored to dredge this up. Doesn't that old wooden boat of yours need some more wax?

I still use this rig on a regular basis and I still love it. I am a big believer in vacuum assisted distillation on the hobby level, but it has never caught any interest, as you can see from this thread. So I just keep on doing my reduced pressure thing, making absinthe and distilling whiskey on the grain with never a concern about scorching. I would post again if I make any great inovations, but I have hit a limit that i probably won't push. I can run at a stable 28 inHg with great results, but if I suck it down below that the collection vessel boils at room temperature. Now there's a strange thing to see.

Thanks for the kind words, Zombie. It's nice to know somebody cares, even if they are just trying to steal brains to eat.
Distilling at 120f and 100 torr
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Tue May 06, 2014 11:24 pm

I'm so glad you have taken no offense. None is meant. :grin:
I have only seen perhaps 2-3 threads that even talk about vacuum distillation, and only one other that is actually running in this manor.. Credit where credit is due. :bow-blue:

There is something here that completely eludes me... How does the boiler vessel maintain a vacuum when by the very nature of "boiling" you are creating a positive pressure? Where do you initiate the vacuum? :think:

Those may be the reasons more people don't take an interest in the whole concept. I think comprehending pressure is instilled in us all from an early age because it is all around us in most everything but vacuum is a rare bird.
It's easy to see the advantages tho. There are quite a few that even a brain suckin' zombie can see.

I appreciate ya Skow! Thanks!! :handgestures-thumbupright: Maybe today I will Un-wax the boat s I can wax it if I ever get that bored again. :grin:

I may need to be "put down" soon.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Wed May 07, 2014 11:07 am

I got nothin' but love for ya, brother Zombie. And I knew you would be curious, and ask good questions. Better watch out or you will be the next guy to suck down a still! [Insert joke here.]

I pull vacuum at the collection vessel. The advantage being that the product is totally liquid at that point, so there is less danger of sucking it into the vacuum source, at which point it would disappear from our universe forever. The disadvantage is that is the farthest point from the boiler, so we have to manage the pressure drop in between. I figure I lose 0.5 - 1 inHg without the thumper and 1 - 1.5 with it. Everything is a tradeoff.

Zombie wrote: How does the boiler vessel maintain a vacuum when by the very nature of "boiling" you are creating a positive pressure?

An excellent question! I've seen guys totally convince themselves that vacuum distillation is impossible just for that reason.

Consider that after a very short period at the start of the boil you reach a steady state where the expansion in the boiler is ballanced by the contraction in the condenser, so the net effect is zero. It's like one of those conservation-of-something-or-other laws where everything has to even out. Or that's how it would work in a perfect world. In reality you have to keep the vacuum source active (a process technically referred to as "suckage") pretty much all the time. The aspirator's output varies with the water flow through it so I can tune it for current conditions. In my case that mostly depends on how much extra suckage I need to overcome my leakage. [Insert really juvenile joke here.]

On my last run the corney started boiling at 108f. The thumper started boiling and distillation began at 114f. You would think there would be a noticable pressure increase during that period from 108 to 114 but it never shows up. That is just one of the interesting artifacts of vacuum stilling that I can't explain. There are better ones.

Are you old enough to remember carburetion, Zombie? Vacuum was critical to that process! A naturally aspirated engine would run with manifold vacuum of 21 inHg, so that is sort of my standard reference level. I tend to think of anything over 21 as good vacuum, 25 starts hi vacuum, and past 28 is scary-assed vacuum. The curve becomes very nonlinear around there, and the amount of force generated is shocking, considering it can't posibly excede 15 psi. 28 inHg turns out to be a kind of a magic number, being right at the knee of the curve, and also the point where the product of a stiripping run, around 40-45 ABV, starts to boil in the collection jar at room temp, which wreaks havoc with your yield calculations.

bp X vac 10%.png

You might notice that I really love talking about this shit, but nobody else gets into it. I don't understand what is wrong with everyone else!

BTW I'm a big fan of Cris-Craft.

Skol,
skow
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Wed May 07, 2014 4:44 pm

I had the thought the "maximum suckage" (are you f'in w/ me?) would be at the collection point.
The way you explain this (much like Myles) is clear, and easy to follow. In fact you make it seem soo easy to build, and actually work that I don't really understand why it is not the accepted "norm"!

I assume the real key to this method is finding/fabricating the components that can tolerate the external pressure while under vacuum. You already have me thinking of an X bracing type design inside a boiler to support the pressure. (actually you had me at "maximum suckage" :shhh: ). I mean I already can see an isolated/insulated vacuum pump (noise control) being monitored, and controlled electronically to automatically maintain a given set point. Truth of the matter is I can understand this concept far easier that the idea of designing a column.

While I have never had any reason to look into anything operating in a created vacuum it almost seems to go hand in hand with distillation. Do you have any insights why this is not the preferred method? Really the advantages in energy/coolant savings are right up front here, and looking at it from an engineering point of view it actually (IMHO) sounds like a much safer method.
I had to let this soak in a bit to realize I would MUCH rather experience an implosion of 104ish degree liquid, and almost instantly condensing vapor than an explosion of 200*liquid, and rapidly expanding vapor. :shock:

Perhaps my initial reaction to your thread on this is the overall conception most people have. But then why didn't any of the smart fellas chime in after 1000 views???

I have a million thoughts flying around like Fireflies. Distillation/vacuum... Peanut butter /jelly. It seems natural.
Once I have a chance to get my pea brain wrapped around this I believe I may have a few worth while questions for you.

Most of all Skow I very much appreciate your good nature, and your Not responding to me with "go boil some water". :roll:

I am honestly intrigued, and most likely won't get much sleep tonight. My quest for Vodka has taken me down some unexpected roads in the past 8 months, and I am VERY grateful to you fellas that have directly, and indirectly helped me understand just some of what you all know.

You're on my Xmas card list Skow! Thanks! :handgestures-thumbupright:

I may need to be "put down" soon.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby RefluxEd » Wed May 07, 2014 5:19 pm

A Great post skow.
I am wondering how much vacuum a 50 litre beer keg can cope with? :confusion-confused:
Also, what cfm rating does the pump need to be?
On looking at your system it appears that it won't take much extra plumbing to convert my still to vacuum.
What appeals is the saving in gas I use to heat up (carbon footprint and all) and the safety factor of working with lower temperatures.
On eBay there are plenty of vacuum pumps that can be got quite cheaply, so it may not take long to offset the cost of the pump against the gas saved.
:handgestures-thumbupright:
2 inch BOKA/LM/VM
Bubbler with 14 4x3x4 inch tees and 15 bubble plates under a 4 inch section under the dephlagmator (RC).
2 inch Pot still.
2 inch to 4 inch Gin head.
2x 1.2 mtre Leibig condensors.
2 inch x 800 mm shotgun condenser.
Love it!
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Wed May 07, 2014 5:50 pm

LOL! Already on it!

http://siba.co.uk/wp-content/uploads/20 ... ns9.12.pdf

That's the spec sheets on kegs. It lists Max sustained. pressure, and Failure Pressure. I'm looking for methods to translate to vacuum or negative pressure (if something exists).

I have a feeling Skow is going to become quite popular here. Bring a bottle, and a few packs of smokes.

I may need to be "put down" soon.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Wed May 07, 2014 5:59 pm

Copy pasted. 14.7 psi being normal atmosphereic

"The cylinder a thin walled vessel so the hoop stress in the cylinder can be found by:-

σ= P*D/(2*t)

for your case if the vessel internal pressure was 10psi
then:-
P= 10-14.7 psi = 4.7psi

σ= 4.7 * 20/(2*0.25) = 188 psi

because the end of the vessels are capped there will be a longitudinal stress this is typically half the hoop stress.

This of course is not the full story because the end caps need stressing and I am not familiar with the Lexan material, the stressing in the end caps will depend on the shape whether flat or spherical etc.
You would be wise to look at ASME 8 or PD5500 which are both pressure vessel codes and should cover vessels under vacuum."

Yup! Google ROCKS!

I may need to be "put down" soon.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby RefluxEd » Wed May 07, 2014 8:14 pm

Wow, thanks Zombie, :text-goodpost:
I'll have to put my science hat on and drag out the ol' HP45 calculator and work out what pressure I can go down to.
I have a keg that has a dented connector, so I'll use that for a sacrificial test to see where it collapses.
Wacko, let the fun begin!
2 inch BOKA/LM/VM
Bubbler with 14 4x3x4 inch tees and 15 bubble plates under a 4 inch section under the dephlagmator (RC).
2 inch Pot still.
2 inch to 4 inch Gin head.
2x 1.2 mtre Leibig condensors.
2 inch x 800 mm shotgun condenser.
Love it!
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Wed May 07, 2014 11:56 pm

Brantoken runs a sanke keg under vacuum, says it works fine. It's a good shape. Not easily crushable. Shape matters a lot for vacuum. Think bell jar. Round things are best. Contours are good. Long straight surfaces are bad.

I don't know that copper pipe has ever been tested for strength. The biggest I use is 1/2 in. There are reports of stainless up to 4" working.

As for mechanical pumps, I think any one I've ever seen would work. Or salvage one out of a refrigerator. Some are louder than others.

21 inHg ~ 225 torr ~ 4.5 psi.
25 inHg ~ 125 torr ~ 2.5 psi.
28 inHg ~ 50 torr ~ 1 psi.

Remember, guys, we can't change the latent heat of evaporation so it costs the same as always to vaporize an ounce of wash. The only heat savings are in the warmup.

Zombie, you're starting to make me nervous. I'm not sure it's fair to advertise anything here as a safety feature.

But it is pretty cool to see some interest in vacuum stillin!
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Thu May 08, 2014 9:57 am

In a hobby where everything involved can/will kill you Including the end product... Advertising is the last word I would use, and I understand your point.

What are the numbers you posted here:
21 inHg ~ 225 torr ~ 4.5 psi.
25 inHg ~ 125 torr ~ 2.5 psi.
28 inHg ~ 50 torr ~ 1 psi.

Latent heat of evaporation... Meaning the time consumed to evaporate is constant regardless of the temp. or the energy consumed is constant relative to time/temp. ie: it takes one ounce of fuel to distill one ounce of ethanol regardless of time or temp.

I'm really impressed with how simple your rig is compared to one I saw on (some other site) that had computers/solenoids/tubes, and hoses/flux capacitors everywhere, and hes was distilling at something like 2-3inHG in an attempt to maintain a stable, and repeatable distillation system. He had also stated approx 4G's in the rig.
Seeing your simple set up is what sparked my interest. I couldn't care less when I saw all the doo-dads, and thingamabobs on the 4G rig because after all you don't NEED a Bently to go buy milk.

How would Vacuum effect a Plated or tray column? Do you know of any work or examples there?
I'm in grave danger of becoming too smart. I hope there is an end to all this.

I may need to be "put down" soon.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Fri May 09, 2014 4:59 pm

Hey Zombie!
I love your enthiusiasm. But do me a favgor and read this: http://www.erowid.org/archive/rhodium/chemistry/equipment/distillation4dummies.html. Especially the section on vacuum distillation, and make note of the discussion of bumping. Also reasons why you apply vacuum before heat. I just don't want to be the guy who led you down the primrose path when you blow your shit to kingdom come.

Zombie wrote:In a hobby where everything involved can/will kill you Including the end product... Advertising is the last word I would use, and I understand your point.

Riteon! It's a hobby for responsible, informed adults. Whatever happens, ain't nobody to blame but us.

What are the numbers you posted here:
21 inHg ~ 225 torr ~ 4.5 psi.
25 inHg ~ 125 torr ~ 2.5 psi.
28 inHg ~ 50 torr ~ 1 psi.

I wrote those numbers in reaction to your calculations for material strength where you said "for your case if the vessel internal pressure was 10psi." 10 psi is pretty wimpy vacuum. Check the graph. These numbers are more realistic for getting a serious reduction of the boiling point.

[Although I should mention there is one group that advocates what they call VAD "vacuum assisted distillation" for making fuel. They say the appropriate pressure is 17 - 21 inHg, and anything over that is out of bounds. I just can't see settling for a 50 deg reduction of BP if I can get 100 degrees.]

Inches of mercury column (inHg) is the standard automotive measure of vacuum, indexed at atmosphere, so ambient pressure is 0 inHg, deep space is 29.92 inHg. I find it awkward to use the psi scale because we usually think of 0 psi as atmosphere. The torr scale is handy for talking about pressure below atmosphere because it starts at zero. Perfect vacuum is always 0 torr, atmosphere is 760 torr. (1 torr = 1mm of mercury.)

Latent heat of evaporation... Meaning the time consumed to evaporate is constant regardless of the temp. or the energy consumed is constant relative to time/temp. ie: it takes one ounce of fuel to distill one ounce of ethanol regardless of time or temp.

The second one. The heat required to vaporize water is 43 kJ/mol at atmosphere, at 100 torr, or at 100 psi.

I'm really impressed with how simple your rig is compared to one I saw on (some other site) that had computers/solenoids/tubes, and hoses/flux capacitors everywhere, and hes was distilling at something like 2-3inHG in an attempt to maintain a stable, and repeatable distillation system. He had also stated approx 4G's in the rig.

Yeah, I wish I had bought stock in solenoids before he started that rig.

Seeing your simple set up is what sparked my interest. I couldn't care less when I saw all the doo-dads, and thingamabobs on the 4G rig because after all you don't NEED a Bently to go buy milk.

How would Vacuum effect a Plated or tray column? Do you know of any work or examples there?

Same as a pot still. Never seen it tried on the hobby level but it should work great, assuming a reliable method of keeping the vacuum constant. And the plates would support the column walls. The petrolium industry uses scads of 'em. BIG mofos.

I'm in grave danger of becoming too smart.

I don't worry about that. Spent too much time being too dumb.

I hope there is an end to all this.

Never!


Skol,
skow
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Rectificato ergo sum.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Fri May 09, 2014 8:31 pm

You sure know how to turn a phrase brother Skow. It's been a very long day, and you put a smile right at the end of it.

The guys that work for me are getting pretty damn tired of finding me at the computer with 8 or 9 open pages, pens, and paper all over the place, and me not having the time to answer any of their questions. Just when I thought it was getting normal again I get sucked into a vacuum.
I appreciate the link. It's my first task of the day.

I may need to be "put down" soon.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Fri May 09, 2014 10:16 pm

Har! You remind me of my days at the *** factory and Ron yelling, "Goddamnit skow, you need to delagate! What if you get runover by a truck? Then I'm in trouble." He was a real compassionate guy. I miss him a lot. :liar:

You better start a couple more projects. Your off season starts now, right? My daughter was working at a resort in the keys, she came home two weeks ago. And, of course, working for yourself, everybody knows, you can take as much time off as you like. Har! I crack me up! Har!

On the other hand, how bad can life be when you're living in paradise and get paid for playing with boats all day? I know a couple of coal miners in Wyoming that'll trade places with ya.

Nothin' but love,
skow
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Sat May 10, 2014 12:24 am

Now you got me thinking about shit.

Here's an interesting idea.

ams_simple_vacuum_still.jpg
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Sat May 10, 2014 4:12 am

Tourist season is over but my season is just starting. I have 50-70 regular customers plus whatever I pick up. Get them ready for the summer/fix what ever they break, and try to get in a major restoration when one is finished. Most restores are 3-4 year projects so I have 24/7/365 work.
Just priced a Trimaran strip, and re gell coat job that will pay for the still. so that made me smile

It's tough man. I have between 4-6 guys that NEED that pay check. Ten year mortgage on the house, and two pieces of property that I am paying rent on to run the business from.
Pick any day of the week, and ask me if I'd trade it all for a nice cushy job in the coal mine. That bust ass job is ten fold easier than keeping all this up in the air.

Forgot what the post was about...

I understand the flow chart you made but maybe because I haven't gotten to read the link you posted (yet) I don't understand what the green thing is or the purpose of the "ice trap".
Maybe some type of filter, and the ice trap to remove any latent vapor/humidity?
You also mentioned the word "bumping". Is that some sort of transition phase between pressure, and vacuum?

I may need to be "put down" soon.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Sat May 10, 2014 4:28 pm

Dude, you sound a little tired. You know, the only thing worse than having too much work to do is not having enough. Hang in there.

I understand the flow chart you made but maybe because I haven't gotten to read the link you posted (yet) I don't understand what the green thing is or the purpose of the "ice trap".

No. That is a diagram of a still in the design stage drawn by Aaron Schnell, a former member of another forum. I just stumbled on to it last night and thought it looked interesting because of the arrangement of the condenser. Unfortunately, Mr. Schnell met his end in a car crash before I became interested in distilling.

Bumping is like a flash boil. It's what they use boil stones for. Causes puking. It can happen at room temp under vacuum when the wash degasses, especially if you slam on the vacuum too fast. Boil stones don't work cuz there's no air in the pot. A capilary tube to leak a little air in helps. So does stirring or agitation if you can do it. It can be very violent. Mine jumped 3 inches once before I figured it out.

Have a weekend.
Skow
Distilling at 120f and 100 torr
Rectificato ergo sum.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Sat May 10, 2014 11:58 pm

Tired is a polite word for it...

I get the "bumping now, as well as the need for the capillary tube.
I have seen the phrase "ice trap" somewhere else as well but haven't tied it in to anything I can grasp yet. I'll get it tho!

I may need to be "put down" soon.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Sun May 11, 2014 11:53 pm

The ice trap ensures that any vapor that got sucked into the vacuum port is condensed and trapped before it goes to the pump and causes trouble.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby rickyd » Mon May 12, 2014 12:50 am

The total energy of an isolated system remains constant. So transfers don't appear this is explained my friends in the Bernoulli effect of fluids in hyper physics.
Also conservation of energy in an isolated system is a constant. This will exhibit a strong constraint on the types of motions which can occur in an isolated system
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby rickyd » Mon May 12, 2014 12:57 am

God dam you are running some gear Ed I know mirco breweries with less stills : :handgestures-thumbupright:
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby rickyd » Mon May 12, 2014 1:06 am

Skow
That rig looks like something outa a backwood science class amigo :)
Ok after a long arduous read through all those posts I don't really see any distinct advantages in the hobby setting in vacuum distilling except for some small savings at take off. However me being me I am tempted to build one similar with perhaps a bit more glass just cause I be one of the few sumbitches that have a rig running vacuum system. So pardon my backwoods education but what are the real advantages in running this system guys as I must be missing the big picture
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Mon May 12, 2014 10:01 am

I only dare to give what I THINK is the answer... If the equipment is properly selected, and rated for the use, the savings in boil up energy, and coolant energy are worth the effort. I use almost a whole months worth of electricity in 2 weeks of hulling, drying, grinding,mashing, distilling,and running the coolant system. I couldn't afford to run weekly/monthly.

The second advantage is lower overall temps. I'd rather be hit w/ a 104* catastrophe than a 200* life changer.

Like I said I don't know enough yet to give an informed answer that Skow can give so I am sure the advantages are many more than my "overview".

Some things just make sense. I believe this is one of those things. :handgestures-thumbupright:

Glancing back you already answered your question...
"Also conservation of energy in an isolated system is a constant. This will exhibit a strong constraint on the types of motions which can occur in an isolated system"

Eliminate thew variables, and you eliminate the problems.

I may need to be "put down" soon.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby rickyd » Mon May 12, 2014 1:20 pm

Yes I guess I somewhat answered it in terms of energy however to me the energy savings would hardly be worth the effort my electricity bill is around $700 per 2 months and probably 1\3 of this is still related. this is minimal compared to some of my mates whose hobby's have a more shall we say hydroponic lean
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Mon May 12, 2014 7:05 pm

rickyd wrote:The total energy of an isolated system remains constant. So transfers don't appear this is explained my friends in the Bernoulli effect of fluids in hyper physics.
Also conservation of energy in an isolated system is a constant. This will exhibit a strong constraint on the types of motions which can occur in an isolated system
I'm not sure how to respond. Could you expand on the relevance, please?

rickyd wrote:God dam you are running some gear Ed I know mirco breweries with less stills :
Did you post this to the right thread?

rickyd wrote:Skow
That rig looks like something outa a backwood science class amigo
Ok after a long arduous read through all those posts I don't really see any distinct advantages in the hobby setting in vacuum distilling except for some small savings at take off. However me being me I am tempted to build one similar with perhaps a bit more glass just cause I be one of the few sumbitches that have a rig running vacuum system. So pardon my backwoods education but what are the real advantages in running this system guys as I must be missing the big picture
To be clear, I have never claimed that vacuum would solve all distillers problems. It's just one more tool in the box. Unfortunately, it's one that is often discounted out of hand.

In all honesty, I had never thought of the safety aspects of running at lower temperatures until Zombie brought it up.

Absinthe is one of my favorites. It is always distilled with the herbs in the pot, which can be a real challenge. The taste of burnt sagebrush will really screw up your absinthe. I was experimenting with the process one time and actually ran the boiler dry. The flavor profile didn't suffer at all and I just rinsed a gallon and a half of plant matter out with a hose. No muss, no fuss.

The original impetus for this thread was my discovery that I could make all grain whskey in a single vessel. I like distilling on the grain. It seems to me that I capture all of the product that way. I don't know how much is left behind when you sparge or rack. Maybe it is inconsequential, but wahatever it is, I am not losing it. Beyond that, I just don't enjoy sparging or rinsing the mash, and I'm not a big fan of cleaning either, so I like keeping the process confined to a single pot. And, once again, scorching the charge is not even on the radar. That should catch the attention of anyone who has tried distilling on the grain.

Vacuum can also save half or better of warmup time, and there are other esoteric tricks like using household hot water for a heat source, but I didn't start this to prosthelytize, I was just describing my rig.

If non of this rings true for you, I probably wouldn't go to the trouble of sucking down a still just to say you did it. It might not be as easy as it sounds.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Mon May 12, 2014 9:09 pm

I just had a thought...
I have a solar water heater assist rig on the roof. Its 300 feet of 1.5" black polybutylene pipe, and it gets up to 160* in the summer. I have a propane hot water heater but it never fires for 8 months out of the year, and it actually tempers the higher temp of the solar heated water
I'm thinking free stillin'. I could easily set up a recirculating pump on a PID to manage boiler temp. I know... Relative to diminishing Alch. content. Or manage vacuum to compensate for diminishing Alch., and maintain a constant boiler temp.. This gets more interesting by the day.

Just saw a light bulb moment!!!
Fuel Ethanol is in it's infancy here in Fl. but we are poised to be the nations leader in production.
Solar powered Vacuum assisted distilling has a real shot at turning the corner for the market.
I will hunt down the MF that tries it here first! :-o

Except Skow, and Myles. We'll partner up 50/50/50! :handgestures-thumbupright:

I may need to be "put down" soon.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Tue May 13, 2014 1:22 am

Yer on, Zombie. Fire up.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby rickyd » Tue May 13, 2014 12:27 pm

skow69 wrote:
rickyd wrote:The total energy of an isolated system remains constant. So transfers don't appear this is explained my friends in the Bernoulli effect of fluids in hyper physics.
Also conservation of energy in an isolated system is a constant. This will exhibit a strong constraint on the types of motions which can occur in an isolated system
I'm not sure how to respond. Could you expand on the relevance, please?
sure you mentioned the laws of constant energy earlier in your post I believe these laws and theory go some way to explaining the differences you couldn't explain of course I may be wrong I have been many times before 8-)

rickyd wrote:God dam you are running some gear Ed I know mirco breweries with less stills :
Did you post this to the right thread?

rickyd wrote:Skow
That rig looks like something outa a backwood science class amigo
Ok after a long arduous read through all those posts I don't really see any distinct advantages in the hobby setting in vacuum distilling except for some small savings at take off. However me being me I am tempted to build one similar with perhaps a bit more glass just cause I be one of the few sumbitches that have a rig running vacuum system. So pardon my backwoods education but what are the real advantages in running this system guys as I must be missing the big picture
To be clear, I have never claimed that vacuum would solve all distillers problems. It's just one more tool in the box. Unfortunately, it's one that is often discounted out of hand.

In all honesty, I had never thought of the safety aspects of running at lower temperatures until Zombie brought it up.

Absinthe is one of my favorites. It is always distilled with the herbs in the pot, which can be a real challenge. The taste of burnt sagebrush will really screw up your absinthe. I was experimenting with the process one time and actually ran the boiler dry. The flavor profile didn't suffer at all and I just rinsed a gallon and a half of plant matter out with a hose. No muss, no fuss.

The original impetus for this thread was my discovery that I could make all grain whskey in a single vessel. I like distilling on the grain. It seems to me that I capture all of the product that way. I don't know how much is left behind when you sparge or rack. Maybe it is inconsequential, but wahatever it is, I am not losing it. Beyond that, I just don't enjoy sparging or rinsing the mash, and I'm not a big fan of cleaning either, so I like keeping the process confined to a single pot. And, once again, scorching the charge is not even on the radar. That should catch the attention of anyone who has tried distilling on the grain.

Vacuum can also save half or better of warmup time, and there are other esoteric tricks like using household hot water for a heat source, but I didn't start this to prosthelytize, I was just describing my rig.

If non of this rings true for you, I probably wouldn't go to the trouble of sucking down a still just to say you did it. It might not be as easy as it sounds.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Tue May 13, 2014 5:56 pm

rickyd wrote:
skow69 wrote:
rickyd wrote:The total energy of an isolated system remains constant. So transfers don't appear this is explained my friends in the Bernoulli effect of fluids in hyper physics.
Also conservation of energy in an isolated system is a constant. This will exhibit a strong constraint on the types of motions which can occur in an isolated system
I'm not sure how to respond. Could you expand on the relevance, please?
sure you mentioned the laws of constant energy earlier in your post I believe these laws and theory go some way to explaining the differences you couldn't explain of course I may be wrong I have been many times before 8-)


Oh I see. But that is contradicted by the Schrodinger equation because the energy becomes the Hamiltonian operator so H(psi)=E(psi).
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby rickyd » Tue May 13, 2014 7:04 pm

God dam I missed that now I hate you too :P Na I dig what you doing its extremely interesting and I will be following your progress and Zombies to until he blows himself up :violin:
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Wed May 14, 2014 12:20 am

Been there / Done that. Yawn...

I may need to be "put down" soon.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby FourofSix » Wed May 28, 2014 1:05 am

Hello Skow,
How long is a typical run from start to finish in your reduced pressure system?

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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Mon Jun 02, 2014 4:56 pm

It's definitely not optimized for speed. It takes about 15 minutes to warm up, and then around 2 hours to collect 3 to 4 quarts.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Wed Jun 04, 2014 3:22 pm

I would assume that is due to the smaller (but in scale stronger) lyne/collection arms. It would take some monster thick pipe to up scale the outputs.

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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Wed Jun 11, 2014 7:31 am

I dunno Zombie. I've got an idea for a 2" vacuum VM. I'm sure stainless would work, but I'm thinking of making it in copper. I haven't found a way to calculate the strength, so I guess I'll test a 2 foot piece to see if it holds up. Got any ideas?
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby Zombie » Wed Jun 11, 2014 8:24 am

My second favorite web site...

http://www.engineeringtoolbox.com/

I believe you can cross reference what you need there. I'm not sure how burst strength translates to vacuum resistance but maybe there is some sort of formula that can translate the numbers.

Short of that how about Copper Plating the interior of a stainless pipe?

They do make that super thick copper pipe (forget what it is called) but I guess you would still need some numbers before investing in something like that. I would think Burst strength transposed into vacuum would get you in the ball park. Or perhaps those labs that test all this sort of thing. I have found lots of engineering forums where they make us all look like Special Education candidates...

I have ideas( not all good0 but they keep coming. If I can come up w/ a few free hours between the 8 dogs/5 cats/one Gf, I'll see what I can come up with.

I may need to be "put down" soon.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby skow69 » Wed Jun 11, 2014 1:07 pm

I found it! In Copper Tube Handbook ref (pg33)

So 2" type M, wall thickness .058", shows a collapse pressure just over 1000 psi. No problem.

Seems surprisingly high at first, but then consider I had to suck a Corney keg down to 29 inHg to collapse it. It had a wall thickness of ~.060 (as close as I could measure) and radius of 4". Reducing the radius to 1" has to multiply the strength immensly. Comparing copper to stainless is apples to oranges I know, but it gives me a mental reference for the effect of the radius. So I think I buy the 1000 psi.
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Re: Reduced Pressure Cornelius Potstill for 1-Pot AG

Postby zapata » Tue Sep 09, 2014 5:36 pm

Skow, just want to give you a few words of encouragement, thanks, and merry. Anybody who drops a link to erowid into a casual conversation must be some kinda kindred to me. I love that you aren't pimpin' your genius, just sharing it eloquently and modestly when asked. I also love, and hope I don't offend, but I LOVE how NASTY your setup is. I got a bigger kick out of it than I have any of the gleaming blinging flutes and towers I've looked at lately. I've never gotten around to cleaning the charred flux off the outside of my cross flow condensor, and I built that thing probably 6 years ago! I appreciate copper porn as much as the next man, but Cu-porn is some PG-13 clothes on second base crap compared to the raw bondage of your corny's black steel gimp band and the medieval torture oil pot beneath it!

Vac never gets the love in distillers circles, been seeing that for years. So you just do it. Love it.

Anyway, I've got a full lab scale vac distillation setup, 100ml - 2,000ml vessels. Why it never occured to me to hook it up to some copper or stainless, I have no idea! Or even to use it for making small scale absinthe or gin, or even concentrates of such. The on-the-grain benefits for whisk(e)y finally seem obvious when I see you just doing it.

Really just wanted to say thanks and kudos, but figure I can add a small contribution. You mentioned recirculating water for your aspirator. It works fine, the only problem is that vacuum will go down as the temperature increases, and the pump will raise the temperature some, eventually. On the small labscale ice is often used to chill the aspirator water, either to get maximum vac, or more often just to keep it more constant so it doesn't drift as the water heats up.
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