From single keg w/bokakob to double boiler

Vapor, Liquid or Cooling Management. Flutes, plates, etc.

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theskaz
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From single keg w/bokakob to double boiler

Post by theskaz »

Hey guys,

I found myself looking around for a new thing to build. I have to be honest, I get more enjoyment out of building things than drinking them. My friends seem to benefit from that greatly. I currently have an EHERMS electric brewing setup with a homemade control panel for my beer, and a keg with a 2" x 3' bokakob column and 5500w element for distilling. My pain point, if you look at some of my threads, is that I can never apply 100% throttle to that keg without puking. it takes all day to run 1 charge. Also, I have a 30Gal fermentor that I received as a gift.

That leaves me with a couple of issues:
1. As mentioned, My 2" column isnt good enough for that heating element.
2. I have to do multiple stripping runs as my boiler is 1/2 the size of my fermentor.
3. The Bokakob was my first and crappiest copper job.
3. I have an itch to build that needs to be scratched.

I, then, saw this gem:
Image

and fell in love with it. Now, Im not that smart with condensers and a lot of the science that goes along with this, but it's purdy. So, my idea is that I build this, reuse my existing keg, and get another one. I use 2" copper and expand to 3 at the "T" and run 3" all the way up. I would use another 5500w element in the other keg, and use 3 digital temp sensors (DS18B20s) that will hook into my brewing control panel. One sensor would be in each keg, and one in top of the column. I would expand by brewing controller programming to allow me to control the various aspects of the still through the touch panel. I bring a few questions to you:

1. will 3" be enough to handle 11k watts?
2. how tall from the T should the column be? I am guessing 4-5' with packing
3. I am lost on the sizing of the condenser. Should it be the same outer diameter as the column, or can it be smaller? or a better question would be "how should I size the condenser?"

I am looking for answers myself, but as you can see, there is a TON to read through and I wanted to bounce my ideas off of some experts.
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Re: From single keg w/bokakob to double boiler

Post by Pikey »

A proper reflux still will always take a longtime to run - that's just in the rules. You cannot run a Boka at 5.5 kw - Can you ??? :shock:

That picture of yours looks like a combination of a pot still, with a couple of perforations through A column to give a little coolant managed reflux - a compromise at best and does not have the flexibility of a boka to run as a proper reflux and also get close to apot.
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Re: From single keg w/bokakob to double boiler

Post by theskaz »

I dont know if you can in general, but mine will puke with anything over 65% power. I understand refluxing does take time, and in all reality I would like to be able to reflux, or not, which brought me to the bokakob design to begin with. The biggest thing that the picture brought to my attention was the 2 kegs feeding 1 column. I know that is 2" all the way up, and knowing that I would run 2x 5500w elements, a 2" column wont do it. I'm still looking through designs. I dont want to get too crazy with it, but I would like it to be versatile.
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Re: From single keg w/bokakob to double boiler

Post by Pikey »

theskaz wrote:I dont know if you can in general, but mine will puke with anything over 65% power..
Of course it will :) You turn the power down when it starts to boil.

65% of 5.5 kw is still taxing your kit to it''s limits - all sorts of "ooo-er's" coming over. calm down and run gentle :)

[edit - stay where you are - that kit does not look good - where did you find it ? ]
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NZChris
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Re: From single keg w/bokakob to double boiler

Post by NZChris »

If you are going to use two kegs, consider building a Charentaise style preheater to cut down on energy costs and warm up time.
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Re: From single keg w/bokakob to double boiler

Post by Pikey »

NZChris wrote:If you are going to use two kegs, consider building a Charentaise style preheater to cut down on energy costs and warm up time.
+1
theskaz
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Re: From single keg w/bokakob to double boiler

Post by theskaz »

NZChris wrote:If you are going to use two kegs, consider building a Charentaise style preheater to cut down on energy costs and warm up time.
Ill look into that. I appreciate the feedback.

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Re: From single keg w/bokakob to double boiler

Post by zapata »

I don't think there is a reasonable way to split the reflux between 2 boilers. Without doing that, each boiler will end up feeding a different mixture into the column which I imagine would play havoc on reaching equilibrium and maintaining it. I see no benefit to that design at all, only drawbacks.

If you want a bigger boiler, get one. A bigger boiler won't speed up your runs, but will save you an hour or so of heatup time on back to back runs, which a preheater could also do without the drawbacks of 2 boilers. I see the logic of a large stripping still, and have one myself, mighty convenient to strip straight into the spirit still.

If you want to go faster, first understand you are going way faster than most would recommend already, at least measured in power. I don't see pulling a good neutral at 3575 watts in a 2" column. That's double the optimum vapor speed. I don't see that as anything other than a lot of smearing, and quite honestly I'm amazed it isn't choking flooding and puking with any reasonable amount of reflux. Even if going for a flavored product, I run much less power through a 2" column.

But, since a 3" pipe has about 2x the area of a 2", upgrading to 2" would let you run at your current power.

If you want to speed up your stripping runs, do them without packing, a 3" riser on a pot still won't be noticeably faster than a 2" riser, and a 2" riser can easily handle full 5500 w power as long as your condenser can handle it.

Overall I think you might be barking up the wrong tree if you your main goal is faster runs.
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Re: From single keg w/bokakob to double boiler

Post by theskaz »

Ok, so, that design above is out the window. It was a thought, and not all are good ideas. That's why I brought that here. Thank you guys for breaking it down. But that leads me to want to improve my own setup anyway.

@zapata, The way that I run my still is by running 100% power until 150F. about 1-1.5 hours in the summertime. then I bring it down to 50% and when Ive got my foreshots, then close my needle valve for a while. I have a 3/4 in CSST condenser that comes down about 8" into the column. I run a pencil lead sized stream until I am into my hearts, then I bump it up to 55-60-65 wherever it doesn't puke. I run all grain washes, so puking is a big thing for me. it has happened every time. I have even had to go down to 30% power just to get it past foreshots and into heads before I can turn up the heat a little. Its that initial surge that gets me every time. I never go over anything more than a trickle out of the tap. Now, that is a spirit run fully packed with copper mesh. it takes me 12-14 hours on a 6-7Gal charge of low wines. The good stuff comes out @ ~190 proof.

with a stripping run, I remove the packing and I still cant apply any more power, maybe even less, or it pukes. I was under the impression that on a stripping run, I could run full blast. That isn't really the case. I might have been wrong in thinking that.

I run fermentation (all grain) in 30Gal batches with about 10-12% ABV. In a perfect world, I would strip that in one run, and turn right around and do my spirit run with as much efficiency as I can.
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Re: From single keg w/bokakob to double boiler

Post by Swedish Pride »

you need to leave a bit of head room when you run AG, i find if I fill over 40l in a 50l keg it will puke unless i drive it slow.
with 40l charge i run flat out until i feel teh copper is startign to feel warm to the touch, then i dial it down to just over half the power and let it sit there for 20 min and gradually increase it.

If i strip i just let it puke, no bother of it does, you're going to rerun it anyways
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Re: From single keg w/bokakob to double boiler

Post by theskaz »

my issue with puking is that it comes out the top and outside of the column and down on the ground.
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Re: From single keg w/bokakob to double boiler

Post by zapata »

So, lotsa options here. For stripping, anti-foam helps. Making sure to degas the wash helps foaming too, like whipping the crap out of it. A true pot still head would make pukes matter less, I personally aim to never puke but understand most people don't worry about it on strips (except obv in your case where the bok spews it out the top).

A bigger boiler for stripping would certainly simplify things. 30 gallons, allowing for 20% headspace would require a 37.5 gallon boiler, but thats too big to talk about here (I think, right? Rule here is max 30 gal total capacity, not wash capacity?)

Before addressing anything else, lets talk goals, what are you trying to make and are you happy with it? All grain and 190 proof could be either a vodkaish or whiskey depending on cuts and blending. What are you shooting for? Aging?
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Re: From single keg w/bokakob to double boiler

Post by NZChris »

A knob of butter will tame the pukes somewhat.

A dedicated stripping head and Liebig would keep your still clean.
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Re: From single keg w/bokakob to double boiler

Post by theskaz »

I typically make whiskey thus far That is pretty much my #1. made a couple vodka-ish runs, and just plain shine. I have a 10Gal American white oak barrel that is currently empty. It has had a 100% barley wash (very conservative cuts) and an imperial russian stout in it. I have a 3Gal that has burbon in it.

I like the versatility of the bokakob.
I dont like the puking.
I would like to do fewer runs to fill a 10Gallon barrel.
I would like a nicer setup.

and in all reality, I just want something to build. my bokakob looks like crap. I would like to use my electronics/programming background to incorporate into my still, as it sits beside my brewing equipment. So, i have 50Amps of power and a water hose available lol.
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Re: From single keg w/bokakob to double boiler

Post by theskaz »

NZChris wrote:A knob of butter will tame the pukes somewhat.

A dedicated stripping head and Liebig would keep your still clean.
I have tried the butter thing. That never seems to work. Maybe not using enough. About 2 tbl spoons for a 12gal charge.

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Re: From single keg w/bokakob to double boiler

Post by theskaz »

So, if i did stripping runs @ 10gal each, that would take 3 days. Each run takes about 8 hours to complete and i stop @200 degrees. Then a 4th for 12 hours of a spirit run. I like what NZChris said about a different stripping head. Then i could run full tilt assuming my condenser could knock it all down

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Re: From single keg w/bokakob to double boiler

Post by NZChris »

A well designed preheater setup should be capable of running that in a day. My downtime to recharge is less than ten minutes and the next charge is pouring a couple of minutes after the power goes back on. If I get a puke, I turn it off for two minutes, then restart at slightly lower amps.

Unless your Boka PC is hugely oversized, it will be too small for a stripping head once the preheater gets hot.
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Re: From single keg w/bokakob to double boiler

Post by zapata »

All the constant talk of back to back runs, multiple runs in a day, saving up low wines, etc makes me roll my eyes a bit at the still size limit rule. I get you have to make a limit of some kind to discourage shady moonshiners, but the rule here seems arbitrary. Tons of folks, maybe the majority, save low wines to do a 12-13 gallon spirit run in a keg. A stripping boiler made to match the keg spirit still would be about 60 gallons if not adding feints to the spirit run. If I wanted to do whiskey faster with fewer runs, I'd strongly consider an appropriately sized stripping still and just not be able to talk about it here. Even if you just matched your ferment size, with a liebig or shotgun that can handle your element you could strip the whole shebang in less than 6 hours including heatup.

That aside, making whiskey at 190 proof in a reflux still is much slower than a pot still. Of course, maybe you prefer your reflux whiskey (I've made good reflux whiskey myself). But for whatever reflux ratio you run, you multiply the time of the spirit run by the same factor. Personally I settled on pot stilling for whiskey, though I probably will reflux some at some point just to be able to do single runs on some experimental recipes.

Have you thought about just using a potstill? Your 8 hour stripping runs could be closer to 2 hours, and your spirit runs not much longer than that. Reflux just takes multiple times longer, no real way around that one.
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Re: From single keg w/bokakob to double boiler

Post by RedwoodHillBilly »

zapata wrote:Tons of folks, maybe the majority, save low wines to do a 12-13 gallon spirit run in a keg. A stripping boiler made to match the keg spirit still would be about 60 gallons if not adding feints to the spirit run. If I wanted to do whiskey faster with fewer runs, I'd strongly consider an appropriately sized stripping still and just not be able to talk about it here.
That is a viable solution.

Further deponent sayeth naught.
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Re: From single keg w/bokakob to double boiler

Post by theskaz »

I have an idea.....

I'll be back.
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Re: From single keg w/bokakob to double boiler

Post by Pikey »

zapata wrote:
....Before addressing anything else, lets talk goals, what are you trying to make and are you happy with it? All grain and 190 proof could be either a vodkaish or whiskey depending on cuts and blending. What are you shooting for? Aging?
Good point zappy - If you want whiskey - why on earth are you pushing the abv to 95% :shock:

If you're going for neutral - why use AG ? :?
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Re: From single keg w/bokakob to double boiler

Post by theskaz »

Still like the double boiler for stripping volume and part reuse. So i thought i could build a CCVM still (DAD300 thread) and keep things modular so i could run 1 or 2 boilers. Really crude drawing and i would be using software to control the heating elements. Its a really rough sketch, but does it make sense?

This would allow me greater volume for stripping, reuse of parts, control reflux based on what I'm making, and i get to play with a torch.
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Re: From single keg w/bokakob to double boiler

Post by Pikey »

RedwoodHillBilly wrote:
zapata wrote:Tons of folks, maybe the majority, save low wines to do a 12-13 gallon spirit run in a keg. A stripping boiler made to match the keg spirit still would be about 60 gallons if not adding feints to the spirit run. If I wanted to do whiskey faster with fewer runs, I'd strongly consider an appropriately sized stripping still and just not be able to talk about it here.
That is a viable solution.

Further deponent sayeth naught.
In honesty, it would be both faster and more economical to do as NZChris suggests and make a preheater from the second keg.

http://ww.homedistiller.org/forum/viewt ... 87&t=66230

[Please note - I am declaring a vested interest here, since mine is still a work in progress and OP loves to build - I'd like to see him make one :) ]
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Re: From single keg w/bokakob to double boiler

Post by theskaz »

Pikey wrote:
zapata wrote:
....Before addressing anything else, lets talk goals, what are you trying to make and are you happy with it? All grain and 190 proof could be either a vodkaish or whiskey depending on cuts and blending. What are you shooting for? Aging?
Good point zappy - If you want whiskey - why on earth are you pushing the abv to 95% :shock:

If you're going for neutral - why use AG ? :?
Learning. I go AG because of my brewing background. I have done sugar washes, and I did a burbon (steep learning curve on the corn starch) recipe not too long ago. I initially went to the boka because I could do either or. But my best has been from all barley then aged for 1 year.
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Re: From single keg w/bokakob to double boiler

Post by theskaz »

Pikey wrote:
RedwoodHillBilly wrote:
zapata wrote:Tons of folks, maybe the majority, save low wines to do a 12-13 gallon spirit run in a keg. A stripping boiler made to match the keg spirit still would be about 60 gallons if not adding feints to the spirit run. If I wanted to do whiskey faster with fewer runs, I'd strongly consider an appropriately sized stripping still and just not be able to talk about it here.
That is a viable solution.

Further deponent sayeth naught.
In honesty, it would be both faster and more economical to do as NZChris suggests and make a preheater from the second keg.

http://ww.homedistiller.org/forum/viewt ... 87&t=66230

[Please note - I am declaring a vested interest here, since mine is still a work in progress and OP loves to build - I'd like to see him make one :) ]
I am still wrapping my head around that design. I havent figured out how to make the preheater without ripping the top off the keg. I found that thread you linked when NZChris first mentioned it. I haven't ruled it out, just not computing right now.
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Re: From single keg w/bokakob to double boiler

Post by zapata »

Its been mentioned, but the 2 boiler approach is flawed especially for a reflux rig. Theres a reason with all the builds and experimentation you DO see, you see very few doubled boilers, and nobody raving about them being awesome.

It seems you are a bit stuck on modularity and multi-funtionality. Thats fine, but you tried that once and it isnt suiting what you want. Plus, you LIKE to build. So why not build purpose suited rigs?

Your main problem is time, changing your method has the most payback. Building and running a pot still will knock your time investment to a quarter or less of what you're doing. Stripping and spirit running 30 gallons could take about 5 hours stillin time, you're spending 36 hours? Think about the entire concept of reflux, you are literally distilling product and dumping it back in, just to distill it and dump it several more times. If you want to save time, stop doing that. Not that your current methods are wrong, me, Harry, Odin, Mashrookie, Smiley and many others have made good refluxed whiskey. But it takes a LOT more time than a potstill. And while it does make a good drop, to my taste it is not better than pot stilled, especially if it's gonna spend time in a barrel.

If you really don't want to go potstill style ok, bigger column, bigger boiler, stripping still head, preheater, CCVM IF on a bigger column etc are valid improvements. But on the order of maybe twice as fast. Not 4-6x faster like a good pot still. Rigging up 2 boilers in a way nobody else does will achieve little but headache.
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Re: From single keg w/bokakob to double boiler

Post by zapata »

Was just looking at one of my extra kegs and thinking of this thread. Maybe there is a case for your last drawing. If you only use it for stripping, remove the reflux condenser and cap the top T, you would turn that CCVM head into a pot still. In this configuration I don't think you would have problems as long as the 2 kegs were equally charged.

But maybe a better way to utilize 2nd keg would be as a thumper. Not only would you get more volume, but could run the grains in the thumper and save yourself the lautering work too. Wouldn't be a multi-function doodad, but would save you lots of time.
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Re: From single keg w/bokakob to double boiler

Post by raketemensch »

If I was to do anything with a second keg, it would be to build a thumper. You could do 1.5 runs and have drinkable product pretty quickly.

But the reason I haven’t done that is that I have a flute, which I love the hell out of, and which produces great flavored whiskey in a single run.

Did you rule out a flute?
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Re: From single keg w/bokakob to double boiler

Post by theskaz »

I havent ruled out anything. But i dont think building a flute is in my wheelhouse. Although flutes look sexy as hell, i dont understand them enough to design/build one. Im currently researching the preheater and thumper ideas. Ill get back to designing after the weekend.

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Re: From single keg w/bokakob to double boiler

Post by Yummyrum »

If you are going to run two boilers , you should join them together at the bottom at least . This will allow some self leveling and mixing of liquids to ensure a similar vapour mix comes from both . This will help with balancing the reflux between each boiler as well . The bigger the connection between the boilers the better the balance of fluids . If I was going to try this my gut instinct would be at least a 4" interconnection ...... and if it turned to shit well you at least have another triclamp port that could be used as a drain or element port on each keg
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