Making a compound column for perfect separation of fractions

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Making a compound column for perfect separation of fractions

Postby Tropic » Wed Dec 06, 2017 9:40 pm

I’m still considering my first build and will be for the next few weeks so please excuse my way out ides for a bit. It seems like stills are like pancakes - the first one is always not quite right, but I’d like to get close. So if you’re inclined, please let me know if this would work and if not, the physics of why not.

Anyway, what I’m considering is running a still with a condenser in the middle of two lots of packing. I’d run the coolant in the central condenser at 79 degrees C. This is pretty achievable with a high temperature pump circulating the coolant from the condenser and using a solenoid adding small amounts of cool water based on a temperature controlled thermostat. What I’m thinking is that this will run like two stills. The bottom half will reflux the heavier fractions and mostly pass up vapours that condense below 79 degrees. The top will then run like a normal still (I’ll be using a LM head) but the source vapours will be much more pure than coming straight from the boiler. In effect, I’m trying to force perfect separation of fractions.

The other thing I’m considering is making it in parts so I can remove and swap bits around if it doesn’t work or I want to run only the head as a pot still. The head, top packing, central condenser and lower packing will all be able to be separated. I plan to take each section pipe to a muffler man to have 120mm ends turned down so they can slide into the next section below (with Teflon tape to seal it). Is this viable?
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Re: Making a compound column for perfect separation of fract

Postby greggn » Thu Dec 07, 2017 10:38 am

I don't believe that's a very efficient or practical design. The 300mm section is too short to provide meaningful reflux and, in order to create robust reflux in the 600mm section, you'll need to throw so much heat into the boiler that you'll probably overwhelm the reflux condensor.

Make it easy on yourself ... buy a few stainless or copper spools with tri-clamps and make yourself a CCVM.
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Re: Making a compound column for perfect separation of fract

Postby zapata » Thu Dec 07, 2017 12:27 pm

Its not a terrible beginner idea. But I think it shows either a lack of understanding or faith in the natural functions of a reflux still.
Take out your middle condenser, and fill the whole thing with packing. Thats 1.2 meter packed. After reaching equilibrium at full reflux with decent packing and a reasonable power input you will have PERFECT fractionation. Not limited by the precision of your thermometers or valves, or whatever. Just laws of physics perfect fractionation. As in infinte precision. Science is like that, have faith until you have experience. You're just replicating the experiments thousands of really smart people have done before us.

It is after all the only reason a reflux still works at all. The fractions stack up the column by being constantly redistilled. If you really don't trust it, might as well take out both your packed sections and try some other "improvement".

Or maybe try this way of thinking about it. The point of your partial condenser is to stop higher bp components from traveling up the column, right? Well that is exactly what reflux is already doing in a packed column, it is condensing high bp components and sending them down, while vaporizing lower bp components. And it isnt doing it at one spot for one temperature but at a million spots at every fraction of a degree that matters, and "magically" skipping the degrees that dont matter.
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Re: Making a compound column for perfect separation of fract

Postby zapata » Thu Dec 07, 2017 12:41 pm

Hold on, my non metric brain just caught up, this is 120mm diameter pipe? I dont think 1.2 meters will cut it unless you are using SPP for packing. And at almost 5" diameter, you're likely to have problems with any packing, as well as feeding the thing with enough alcohol to work.
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Re: Making a compound column for perfect separation of fract

Postby StillerBoy » Thu Dec 07, 2017 4:03 pm

This setup is something in line to what Darek Bell, at Corsair Artisan Distillery, uses on some of his production units.. he states that it compresses the vapours closer to the boiler, and the vapours that do move on, have a higher proof.. which is also the concept that the ethanol auto industry uses..

And you would not need to have 120 mm long pipe flair, that over 4", 70 - 75 mm long flair would be plenty.. the problem I see in flaring is to be very careful with the fit.. if the gap is too wide, teflon tape alone with not seal, then you will need to use 3/4' tape around the joint area, then a thin sheet of copper metal, and held in place with a 3/4" wide muffler clamp.. and you may want it closer to the boiler, that is the first condenser up from the boiler..

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Re: Making a compound column for perfect separation of fract

Postby Tropic » Thu Dec 07, 2017 6:13 pm

Thanks everyone. I have a few years’ experience with an Essencia Super Reflux CM head and really understand why it doesn’t work well. It is obviously too short to properly reflux. It uses cold water as LM which is a balancing act trying to get the vapour down to the right temperature and flow rate to pass on to the condenser.
I think that by using a much larger internal LM condenser at the right temperature it will compress the vapours as I dictate it. I have a science background, and thus my need to measure and control the variables. I am thinking of doing this to make it more controllable, faster and better tails. Towards the end of the run in a normal column the ethanol content in the vapour runs low and more and more heavier fractions get carried through to the head. I would think that the internal condenser would knock those down low in the column allowing for the top to keep processing higher quality product later in the run. I’m glad to hear that others are already using this so will try to check them out.

And sorry for the confusion. I’m using 63mm (2.5 inch) diameter pipe and will use stainless steel scrubbers as packing. I was thinking of making the turned down ends 120mm (5 inches) long. I’ll drop that down a bit as advised and check the fit of each pipe as it is made.
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Re: Making a compound column for perfect separation of fract

Postby zapata » Thu Dec 07, 2017 11:16 pm

stillerboy, do you have a reference to Corsair's still you are referring to? I poked around but couldn't find anything about them having a packed column still. There are a few things on the tour photos I honestly don't know what they are though, but I did see several pot stills and a plated column. Are you perhaps referring to a more traditional "purifier" on a pot still like in some scotch whisky stills? That would be a similar goal, but totally different from being in the middle of a packed column. Barring Corsair having something novel I didn't find I don't think there is anyone doing anything similar to OP.
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Re: Making a compound column for perfect separation of fract

Postby RedwoodHillBilly » Thu Dec 07, 2017 11:28 pm

Tropic, the concept isn't uncommon. There are those that use a packed column above a plated column. The idea is that you feed the packed column with higher ABV vapor to make the packed section more efficient. If I read your post correctly, this is what you are advocating. If you are trying to get a high ABV, low flavor product, I don't see a problem. There are many ways to skin a cat, and this is just one of them.
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Re: Making a compound column for perfect separation of fract

Postby zapata » Thu Dec 07, 2017 11:39 pm

Tropic, by all means try it if you are convinced. I understand your motivation, physically suppress the tails so they can't possibly rise in the column. I do question the need to do it at all, a good reflux still just sits at azeo all day long before spouting out a bit of tails and being shut down (or automatically shutting down if a good VM). If your still works according to theory it'll also sit at azeo all day and then just shut down without spouting a drop of tails. Some benefit I guess, though I've never really looked at a few jars of tails out of 20 as major burden, it's not like they are smeared into the hearts. Truthfully, I'm usually super tired by then and just turn it off and walk away at the first hint of tails so I barely see them at all.

But just to help you think it through, what is your hypothesis on specifically how this dephlegmator will work any better than the reflux that would naturally be there if it were just a packed section? I don't monitor column temps that low in the column, but I do monitor them at about 1/3 down. I've got azeo there for hours, that temp is the main thing I run my column based on after heads are handled. The reflux keeps the tails suppressed below there until it's time to shut down. Sometimes after a .1 degree rise I'll close the takeoff to restack the column and take another good jar, but often I'm just tired and stop. Even with your still functioning as hoped, production is going to slow down to the same degree as less and less vapor makes it to your upper column. I guess the question remains, why do you really care if you have tails at the lower 1/3 of your column if they don't come above the top 1/3 until your last jar?

And how do you manage the upper LM head with no way of really knowing how much vapor is being fed into the upper column? On a trad LM head you set the reflux ratio by taking off the inverse of known maximum production (based on boiler contents and power input). I guess you can run it blind with unknown reflux rate just by assessing output, or maybe watching a mid column thermometer somewhere?

What if your dephlegmator isn't run perfectly? Will it knock down some heads, trapping them in the lower column longer than necessary and just smearing them longer than needed? Theoretically it shouldn't, but how closely will practice align with theory? How cold is your input water, and how long before it heats to your set point, is it condensing heads and ethanol until it heats up? Will it condense too much and flood the lower section? Again; shouldn't, but in execution?

Your goal however is not a bad one. Though I think it is already solved pretty well in hybrid reflux stills which put physical plate/s below a packed column. Physical plates really do seem to present a physical barrier (rather than "just" a theoretical plate) to higher BP components rising in the column. Which would make them a very good design to also compare your proposal to. They also improve the efficiency of the packed section by feeding them a steadier diet of higher ABV which allows the packing to function at a lower (better) HETP. And with a sight glass they provide a visual cue of the onset of heads (fogging or running dry) Just in terms of height, if you used that 300 mm for physical plates (but placed at the bottom of the column where they are proven to perform best) you could fit at least 2 plates (3 if you give it just a few more mm). A hybrid still with 2 plates and a meter of packing is a proven workhorse in both theory and practice. (I'm not really certain how well plates work in 2.5" pipe, I've not seen smaller than 3" used). Granted it's a more expensive and troublesome build, but so is a novel 1 off, especially if it doesn't work as hoped.

Honestly, I'm of the never done building and experimenting camp so I will applaud you for building it and letting us know either way. The worst that happens is you "waste" some time in the shed, learn a bunch, make some spirits, and maybe have a few holes to patch when you make your next pancake. I've pointed out some theoretical questions but I think you'll hit some practical ones too if you get to the building and running stage. If it's of any help to you, though I'm veering off topic, if I were making a new perfect pancake I would focus on gadgetry for dealing with heads more efficiently as that pays dividends to me that dealing with tails doesn't. I can shut off early and never see tails, but I HAVE to get through heads, and the faster and better you can do that, the more time you save every run and the more and better your hearts are (assuming you still cut in time for the tails). I'm currently playing with a variable volume heads trap to deal with heads during the standard equilibrium phase and not have to sit through bleeding them off. Just food for thought.
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Re: Making a compound column for perfect separation of fract

Postby kimbodious » Fri Dec 08, 2017 3:06 am

Great discussion!
I didn't know there was an Essencia Super Reflux LM still, I thought their reflux still was a CM?
Good point Zapata about always having to deal with heads but being optional about having to deal with tails. I am the same as in choosing to stop as soon as tails appear.
Tropic's design will require two condensers in the column, what are you going to use coils or shotguns? I've got all the components to build a VM still similar to this design but I think I'll stick with my CCVM :thumbup:
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Re: Making a compound column for perfect separation of fract

Postby StillerBoy » Fri Dec 08, 2017 9:22 am

zapata wrote:stillerboy, do you have a reference to Corsair's still you are referring to?

Darek makes reference to it in his book,"Alt Whiskeys", and also has a picture of the setup.. the build is in the style of a dephlegmator, located just at the base of the column..

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Re: Making a compound column for perfect separation of fract

Postby Tropic » Fri Dec 08, 2017 12:17 pm

Hmm, my hypothesis… My original thought was to run a water jacket with a coldfinger the full length of a 1.2m column both held at 79 degrees. Pack s/s scrubbers inside the column around the coldfinger. I theorised that if I ran an infinite length column of this at 78.0 degrees for an infinite amount of time I could pull out all the heads. Then if I ran said infinite column at 78.2 degrees on the remaining wash for an infinite time I’d get pure azeo. There would be no need to reflux anything.
A standard column (or even a column on top of purifying plates) is a balancing game of how much to reflux and how much heat energy to apply to the wash. The longer the column, the easier this is to keep near-pure ethanol coming off the top of the column. The reflux is used as the cooling agent. Instead of using the reflux as the coolant, I thought I could use an intern temperature controlled condenser to as a method to cool the vapour and stop the tails from entering the column at all. Because I can’t have an infinitely long column, I would originally settle for trying to eliminate as much of the tails as I could then refluxing to cool the top half in this design.
But at first, I would run the lower condenser at 77.5 degrees until it ran dry. Theoretically this would remove the heads. Or more amusingly, I’m going to create this in components so could move the temperature controlled condenser to the top of the column, just before the take-off top to ‘polish’ the product, and allow the rest of the column to reflux as normal.
If I can’t remove all the heads then the LM head could be calibrated exactly the same way as normal – run the thing at full take off to assess the theoretical maximum, etc. I’ve heard a constant, definable reflux ratio is one of the holy grails of still design. How about this keeping with my theory of controlling everything? You take off ALL the distillate produced and divide it up manually. Eg, you collect it into a holding container with ten holes in the bottom. You then have two sliding trays – one for collection and the other to return as reflux back into the column that can be moved to collect each of these streams.
Hi Kimbo, the Essencia is a CM, sorry for the typo. I’d use a coil packed with s/s scrubber inside and out for maximum efficiency. You ccvm indeed looks impressive.
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Re: Making a compound column for perfect separation of fract

Postby Saltbush Bill » Fri Dec 08, 2017 1:02 pm

zapata wrote: I do question the need to do it at all, a good reflux still just sits at azeo all day long before spouting out a bit of tails and being shut down (or automatically shutting down if a good VM).

That is the crux of the whole thing, what ever you do you wont build anything different that works any better. So why not just stick to a known design?
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Re: Making a compound column for perfect separation of fract

Postby Tropic » Fri Dec 08, 2017 5:23 pm

Saltbush Bill wrote:
zapata wrote: I do question the need to do it at all, a good reflux still just sits at azeo all day long before spouting out a bit of tails and being shut down (or automatically shutting down if a good VM).

That is the crux of the whole thing, what ever you do you wont build anything different that works any better. So why not just stick to a known design?


To experiment and have a bit of fun with it.
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Re: Making a compound column for perfect separation of fract

Postby The Baker » Fri Dec 08, 2017 8:01 pm

Saltbush said, '
That is the crux of the whole thing, what ever you do you wont build anything different that works any better. So why not just stick to a known design?'.

When I first joined distilling forums Alex Bokakob was doing different things with reflux stills.

Then later people were experimenting with plate stills....

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Re: Making a compound column for perfect separation of fract

Postby greggn » Sat Dec 09, 2017 1:39 pm

I think the prevailing attitude here, with regard to new ideas, can largely be summed up as "Give it a try."

... but usually novices are encouraged to use proven designs and recipes to develop a feel and understanding of how things work before experimenting.


>When I first joined distilling forums Alex Bokakob was doing different things with reflux stills.

I assume that the still design commonly referred to as the "Boka" was not his first build. In this case, the OP is building his first.
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Re: Making a compound column for perfect separation of fract

Postby Tropic » Tue Dec 12, 2017 7:45 pm

The more I read here, the more I understand that a well designed head on a good column run at the right power and take-off "sits at azeo all day long before spouting out a bit of tails and being shut down". So yes, this may be redundant. But it may have advantages.
If I set it at 70-77 degrees at the start will it cut out / massively reduce ethanol while I remove the foreshots/heads making it a much smaller portion?
If I set it at 78 degrees in hearts will I be able to run the rig harder and faster with greater purity? Will it allow me to run a much shorter column?

I agree that my limited experience with a tiny CM still is not enough to get a real feel for proper distilling. But I'm not about to let that stop me experimenting right off the bat. I don't do 'normal'. Just look at my avatar - that's my chinese crested dog. Building a non-changeable boka or other known design would be way too dull for me.
I'm not an idiot. I'll make this modular so if this small section is redundant I'll just remove it and replace it with a packed section or some other idea. With no-one giving me a definitive reason why it won't work, in a few months you should all know one more thing that doesn't work. Or does! And that seems to be what this site is all about.
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Re: Making a compound column for perfect separation of fract

Postby zapata » Tue Dec 12, 2017 9:49 pm

I don't want to seem like I'm picking you apart, these quotes just stimulated thoughts so please take this as conversational and not combative.
If I set it at 70-77 degrees at the start will it cut out / massively reduce ethanol while I remove the foreshots/heads making it a much smaller portion?

Pretty unlikely. There are likely several azeotropes involved, I know there is at least for ethanol and ethyl acetate. The smallest possible volume would be taken off at it's azeotrope, a mid column dephlagmater can't break that azeotrope to hold back ethanol to make a smaller heads cut. Assuming "normal" rigs take heads at the respective azeotrope/s. Reports and experiments with "dumping" batches of heads while the still is in equilibrium (theoretically at heads azeotrope) rather than a slow bleed makes me think it is likely at least some of us are taking it off at azeo, meaning a smaller volume of heads is actually impossible without monkeying about with chemistry or pressure. It also just makes sense that any still capable of making ethanol/water azeo is also capable of making ethanol/heads azeo too. I don't think even the folks claiming to hit the near mythical "2nd azeotrope" of what is it, 97.2%abv in tall spp columns are claiming drastically smaller heads cuts. Any improvement here is likely to be margin of error small.
If I set it at 78 degrees in hearts will I be able to run the rig harder and faster with greater purity?

Maybe. It's theoretically possible, and would be great it if works out. I don't think it will, because I don't think your condenser will be perfect and will in fact be knocking down a fair bit of the ethanol you actually want to pass. Cranking it up harder to make the top column produce faster may well choke the lower column. It's even possible the imperfections in the dephlagmater simply prevent the upper column from ever being in equilibrium undermining the performance of the entire still. But it is theoretically possible, and I'd love you to discover it.
Will it allow me to run a much shorter column?

Take away the "much" and I think this is your most likely hopeful outcome. Once everything is tuned and balanced, will it outperform an equal height of packing or a hybrid still? Or can it at least prove the mechanism by which a mid column dephlag could be designed to be as compact as possible and then outperform an equal height of packing? You don't necessarily need to hit a home run to prove the idea can play ball.

Maybe more exciting though, there may well be some other mechanism or tweak that makes this design rock. You seem committed to it, so I hope there is. Who knows what it might be? Maybe it ends up being a perfect "1 and done" whiskey or rum still. Maybe it works well enough that you can effectively keep the upper column at a ridiculously low reflux rate, maybe it just flat out blocks all tails and we all learn that what we thought was neutral actually has a hint of tails taint, maybe...who really knows. If you really just wanted to see if someone could straight out disprove it, nobody did. The worst you got was "meh, I don't think it's awesome". So sure, build it and let us know. :clap:
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Re: Making a compound column for perfect separation of fract

Postby Yummyrum » Tue Dec 12, 2017 9:52 pm

Tropic good luck with build . I'm curious how you intend to " set" the deflag temp . Guys that have placed a thermometer directly above and below them get quite different readings .
I would imagine that it will take a while for both columns to stabalise and if you adjust the deflag during the run that it will upset the stability in both columns again . Personally I think it will frustrate the hell out of you but some blokes like fight'n words to encourage them to do it even more :ebiggrin:

Double posted with Zapata .... but I'll keep it the same
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Re: Making a compound column for perfect separation of fract

Postby Saltbush Bill » Wed Dec 13, 2017 1:36 am

The Baker wrote:When I first joined distilling forums Alex Bokakob was doing different things with reflux stills.

Then later people were experimenting with plate stills....

I'm just wondering how we got from Bokas and reflux stills to plated columns ? They are two very different beasts designed to do very different jobs.
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Re: Making a compound column for perfect separation of fract

Postby zapata » Wed Dec 13, 2017 1:57 am

OK, I was getting ready for bed and I just had a separate thought, might as well make a separate post :)

Even if it works the way you want it to, I think the upper column will effectively lose it's heat source and stop producing at some point. Think about it, assume you can build it and tune the dephlag to hold down higher BP components at any given stage. Without higher BP compounds in the upper column, condensing on the reflux and thus giving up their energy to it, what energy is there to vaporize the liquid reflux? It will have to fall all the way through the upper column, fall through the dephlagmater, then it will cool the top of the lower column before being vaporized. The only source of energy for the upper column will be components with low enough BP to get past the dephlagmater. Is that enough energy to effectively run a column? Is it enough energy to produce anywhere near as much reflux as stills as we know them need? At one extreme it almost assuredly wouldn't be enough for just fores if you were able to isolate only them in the upper column. It MIGHT be enough energy for most of heads, though at best sometime in late heads there won't be enough energy to actually clear them from the column due to passive reflux alone until you start letting hearts through past the dephlag into the upper column (which seems like it completely undermines any potential for the dephlagmater to help until at least the hearts/tails transition.
It may look like this at the beginning of heads, top to bottom:
/reflux condenser/
LM takeoff -----> Heads
........................./ Refluxing Heads
Upper Column | Refluxing Heads
.........................\ Refluxing Heads
Dephlagmater set to hold back hearts & pass heads
........................./ Refluxing Hearts / Some heads dripping to here and revaporizing
Lower Column | Refluxing Hearts
.........................\ Refluxing Hearts / Maybe some tails
Boiler

But after you've taken most of the heads it'll stop, in equilibrium from passive reflux like this:
/dry reflux condenser/
LM takeoff -----> Dry
........................./ Dry
Upper Column | Passively refluxing Heads
.........................\ Passively refluxing Heads
Dephlagmater set to hold back hearts & pass heads
........................./ Refluxing Hearts / Some heads dripping to here and revaporizing
Lower Column | Refluxing Hearts
.........................\ Refluxing Hearts / Maybe some tails
Boiler


You'll run into the same "problem"? Scenario? at late hearts. Maybe that isn't bad though, you lose the last bit of late hearts stuck in the column, it's probably not a significant volume and may well be a fair trade to simply not ever make tails unless you really want to (turn off the dephlag). I suspect the above problem means that you wouldn't even turn on the dephlag until you were already into hearts making it a one trick pony, hold back tails.

I don't really know, but try thinking about it like that. It might be your, "nope it can't work". The dephlag will be reducing and at some point eliminating energy input to the upper column.

Or can you actually work with that somehow? If you can really perfectly nail the dephlag to fully block hearts but allow fores and heads, do you even need forced reflux? Is it just wide open throttle on the upper LM for all of fores/heads, effectively running what Complete Distiller refers to as a fractionating still (though fed by a lower CM reflux still)? At some point there's not enough energy to clear the upper column of fores/heads, production stops, you have an obvious cue to open the dephlag up, allowing the hearts to enter the upper column and clear the remaining heads before switching to your hearts container? With heads gone and tails held back at the dephlag do you even need reflux for hearts? Heck, if it works that way, you might not end up needing your reflux condenser or LM trap at all, swap them out for a down turned liebig. THAT would be a drastic discovery, allowing much shorter and simpler stills, a CM under Fractionating hybrid. Discrete high thermal mass packing might have an advantage here, say rasching or lava rock instead of copper mesh, because it would allow a thermal gradient and increased reflux during the transitions, which is when you would really need more reflux.
(OK,have to poop on my own party, I don't think it'll actually work out that way! If it did, you wouldn't even need the upper column at all because without the heat source of lower BP components it isn't actually doing anything. We could all just make 300mm tall CM stills and call it a day....But only you can prove it.)

What are you using to control the dephlag? Because honestly if you could somehow control that dephlag to <1 degree, you might be onto something after all. And what are you measuring/controlling? Coolant outlet temp? Coolant in the middle of the dephlag? Vapor temp above dephlag? What's your coolant input temp gonna be, is it constant or recirculating so rising? Seems like this idea gets "feasible" if you had a insulated dephlag reservoir with a <1 degree dual stage temperature controller, and feed the dephlag a high flow rate of a precisely controlled coolant.

And this is all assuming temperature controlled dephlagmators even work like that at all. I've always pictured the dephlags I've sat and watched (flute style) to actually be working more like a VM valve, in that it's not so much the temperature they work at selectively condensing things, but in allowing different percentages of total volume of vapor through. As in cold dephlag allows 0% vapor through, warm dephlag allows 50% vapor through, hot deflag allows 100% vapor through. Awe, shit, I think that's it...F it, I typed another useless book, I'm leaving it up, but I think that's the "Nope, can't work". Your temperature controlled dephlag isn't going to magically condense individual molecules at the targeted temps, it's dealing with a mixture of vapor. It'll condense all the vapor, some of it, or none at a ratio of it's energy transfer. Evenly for every compound in the mixture, not selectively based on BP. It's about energy transfer, not boiling/condensing temperature. It must be, because if not we really could just set a dephlag on top of a pot still, run it carefully and collect azeo. Ignore everything I said above (well it may be thought provoking even in error) Because I finally think for real all your mid column dephlag is gonna do is reduce the volume of vapor fed to your upper column reducing both take off and reflux and disrupting both columns while you/your controller fiddle with it, it isn't going to do anything to change the composition in the upper column at all, at most it'll act like a single plate. Poll the audience? Phone a friend? I give up, it's taken me about 6 fingers of UJSSM to get this far, that's my final answer. Build it anyway!
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Re: Making a compound column for perfect separation of fract

Postby zapata » Wed Dec 13, 2017 2:04 am

Saltbush Bill wrote:I'm just wondering how we got from Bokas and reflux stills to plated columns ? They are two very different beasts designed to do very different jobs.

Both perfect examples of solid innovations in the hobby. Think Geoff was just trying to support the spirit of innovation and keep the rest of us from resting on our laurels too much. Pre boka, everybody thought reflux stills were perfected. Pre flutes everybody thought pot stills were the be all end all of whiskey stills. As far as we've come, I'm sure there are still advances to be made in the hobby.
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Re: Making a compound column for perfect separation of fract

Postby The Baker » Wed Dec 13, 2017 2:08 am

Saltbush Bill wrote:
The Baker wrote:When I first joined distilling forums Alex Bokakob was doing different things with reflux stills.

Then later people were experimenting with plate stills....

I'm just wondering how we got from Bokas and reflux stills to plated columns ? They are two very different beasts designed to do very different jobs.


The plated stills came a bit later as a result of innovations by different people.

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Re: Making a compound column for perfect separation of fract

Postby The Baker » Wed Dec 13, 2017 2:09 am

zapata wrote:
Saltbush Bill wrote:I'm just wondering how we got from Bokas and reflux stills to plated columns ? They are two very different beasts designed to do very different jobs.

Both perfect examples of solid innovations in the hobby. Think Geoff was just trying to support the spirit of innovation and keep the rest of us from resting on our laurels too much. Pre boka, everybody thought reflux stills were perfected. Pre flutes everybody thought pot stills were the be all end all of whiskey stills. As far as we've come, I'm sure there are still advances to be made in the hobby.


Thanks, Zapata. Right on.

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Re: Making a compound column for perfect separation of fract

Postby The Baker » Wed Dec 13, 2017 2:12 am

And thanks, Zapata, for your technical comments.
Which I am afraid go right over my head but I still appreciate your work.

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Re: Making a compound column for perfect separation of fract

Postby Yummyrum » Wed Dec 13, 2017 2:13 am

Gezz zapata after dumping that , should make counting sheep in you sleep a bit easier :ebiggrin:
I totally agree with 5th sentence from the end :thumbup: .... thats my take on it too . The long post that is
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Re: Making a compound column for perfect separation of fract

Postby Tropic » Wed Dec 13, 2017 6:15 pm

Um, wow. That's a lot to digest.
Well, the aim was to make the system more stable and more controllable but from those comments, it may actually do the opposite. Or will it? It all depends on whether an inline condenser will selectively condense the heavier compounds or not. Or will it just cut down the total vapour without purifying it? The old-styled CM stills with the coolant pipes going through the column in several places seemed to work but were hard to control, and I thought this might act like a controllable version of that concept.
Will the temperature above the condenser drop below 78.1 degrees and thus not allow reflux? Is this a good thing and eliminate the need for the extra length or even the need for any refluxing? Is this a bad thing and stop any vapour getting through? It looks like there's only one way to find out - build the thing and test it.
With this coolant system I think I can manage to control the coolant temperature to within a degree. I'll initially need to measure outlet water temperature as well to see how much difference there is.
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