Heating wattage for 6 inch column

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Heating wattage for 6 inch column

Post by Evil Wizard »

Does anyone have wattage specs for running reflux on a 40% spirit in a 6 inch column? Mine is about 78" high but modifiable.

6" is too big for home distillers and kinda small for craft distillers so I don't see much info online.
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Re: Heating wattage for 6 inch column

Post by sambedded »

There is no magic number for it. Required power depends on many factors, like heat up time, heat loss, column design, packing, condensers efficiency etc. I'd say something around 5000 - 10000 Watts should be OK. You can play with calculator to get a better idea - https://homedistiller.org/wiki/index.php/htm/calc ... x_calc.htm
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Re: Heating wattage for 6 inch column

Post by Evil Wizard »

Thanks, I've been all over that calculator.

To complicate matters its a continuous column taking the output of my continuous stripper, so the boiler volume is only 30L but I have to compensate for the 40% entering the system at not sure what temp yet.

I'm just trying to figure how many elements to install. You think one at 4500w constant and another 4500w on a triac?
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Re: Heating wattage for 6 inch column

Post by cob »

you talking about the kothe? if so the real question is what is it's maximum wattage rating?

this might help it's only 20 gal. you will have to do the math for 1250.

Example: To heat 20 gallons of water by 100°F in 30 mins (0.5 hrs); 3.1 x 20 x 100 / 0.5 = 12,400 Watts
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Re: Heating wattage for 6 inch column

Post by Evil Wizard »

Hi Cob, no I switched jobs and provinces. That Kothe was a 30" column on a 5000L kettle steam driven monster. Day job is now running a big direct fire continuous SOFAC Armagnac still but this question is about my own still I'm building. Its useful for prototyping batches under 5000L fermentation which is what I'd have to do to bother firing up the SOFAC.

100F is 37C, I'm not sure what the utility is in the equation you gave me about raising the temp of water by that amount. Thanks though.

I'm really just after the wattage range needed to suspend 40%+ vapour in a column with an unpacked volume of 36L. I know there're a lot of factors, just looking for a range.
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Re: Heating wattage for 6 inch column

Post by LWTCS »

Turns out,,408 watts, per gallon/per hour is a pretty reliable number.
So if you are looking for a feed rate of 40 gallons an hour, you'll need 1632 available watts.
That input is predicated upon a measure of heat recovery to preheat your beer injection temp.
I'm not sure what you would need if no heat recovery is involved?
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Re: Heating wattage for 6 inch column

Post by LWTCS »

That power requirement is also based on an 8% ABV on the beer feed.
Are you saying that you are feeding a 40% ABV to your injector?

Low wines distillate coming over with adequate dwell time with an 8% beer is about 50%-52%
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Re: Heating wattage for 6 inch column

Post by bluefish_dist »

I ran a 6” column between 8000 and 12000w. My smaller boiler was about 30 gallons of low wines with 8ft of packing and only had 8000w. I would run it at full power. My 120 gallon with 2 or 3 plates would run at 12000w which was full power. By vapor speed, I think you should be able to run a bit more than I did, but I was limited on power.
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Re: Heating wattage for 6 inch column

Post by LWTCS »

So you're talking about a continuous system then yes?
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Re: Heating wattage for 6 inch column

Post by Getsmokin »

LWTCS wrote:Turns out,,408 watts, per gallon/per hour is a pretty reliable number.
So if you are looking for a feed rate of 40 gallons an hour, you'll need 1632 available watts.
That input is predicated upon a measure of heat recovery to preheat your beer injection temp.
I'm not sure what you would need if no heat recovery is involved?
Missing a digit here, 16320. Was scratching my head for a minute, trying to figure out how 1600 watt was going to work.



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Re: Heating wattage for 6 inch column

Post by LWTCS »

Getsmokin wrote: Thu Oct 22, 2020 6:05 pm
LWTCS wrote:Turns out,,408 watts, per gallon/per hour is a pretty reliable number.
So if you are looking for a feed rate of 40 gallons an hour, you'll need 1632 available watts.
That input is predicated upon a measure of heat recovery to preheat your beer injection temp.
I'm not sure what you would need if no heat recovery is involved?
Missing a digit here, 16320. Was scratching my head for a minute, trying to figure out how 1600 watt was going to work.

Ah yessir, sorry.
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Re: Heating wattage for 6 inch column

Post by shadylane »

Evil Wizard wrote: Thu Oct 22, 2020 3:07 pm Does anyone have wattage specs for running reflux on a 40% spirit in a 6 inch column? Mine is about 78" high but modifiable.
What's in the 6" column ?
Packing, bubble caps, sieve plates
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Re: Heating wattage for 6 inch column

Post by hypnopooper »

I run a 6" column that I made. It has 4 bubble plates, and about 40" inches in height. I use (2x) 5500 watt elements to heat up a steam powered Bain Marie style boiler. I heat up with 11000 watts, drop to 5500 watts for pulling product. Im still working out my controller options and efficiencies, as there are times when it feels as though I don't get to the product stage as fast as others. I'm only on my 4th run with this column and control unit. Heat up time with the agitator running is less than an hour to get from 80F to 160F. for 30 gallons of 8-12% fermented all grain mash.
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Re: Heating wattage for 6 inch column

Post by shadylane »

shadylane wrote: Thu Oct 22, 2020 6:36 pm
Evil Wizard wrote: Thu Oct 22, 2020 3:07 pm Does anyone have wattage specs for running reflux on a 40% spirit in a 6 inch column? Mine is about 78" high but modifiable.
What's in the 6" column ?
Packing, bubble caps, sieve plates
It makes a big difference
The "Mine is about 78" high" just sunk in.
I must of had a brain fart, not to realize it's a packed column :lol:
I'm thinking that column needs at least a 25-30 gallon boiler.
The problem isn't going to be how much power the column can handle.
It's going to be how much power, before the boiler starts foaming up and pukeing.
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Re: Heating wattage for 6 inch column

Post by LWTCS »

On the continuous you'll need to be a bit more specific about the design because you shouldn't need any more heat once your feed stock is flashed.

Are you using a kettle and spent feed stock as your steam source?
Are you feeding from a "plate" or feeding into a kettle?
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Re: Heating wattage for 6 inch column

Post by zapata »

Not if it's continuous, just needs a little bitty reboiler (or steam injection and no reboiler at all) if it's being run like a traditional rectifying column. And being a rectifying column it's being fed wines, so not much foaming to worry about.

Wizard, is this a made up design? No offense, but it sounds like it is. And will it really be continuous? There is a world of difference, and a fair bit of resources on running continuous stills in batch mode. The fact that you even use the word boiler vs. reboiler makes me think you don't really have any intention of using it continuously. The design, operation and control of the two is very different. Strange as it seems to most of us batch distillers, real continuous distillation is a relatively simple steady state situation so you just have one set of conditions to design for.

And where and what are you feeding it? Liquid at the bottom? Can you possibly get a low abv bottoms waste stream like that if you really run continuous? I think you'll need a mid column feed to not be wasting a lot of alcohol out the bottom, but again, I really doubt this what you are doing. For one, because you'd have run into these problems on the continuous stripping column too. And a 6" D dual column continuous still would need thousands of gallons of wash a day to reach and maintain steady state conditions, that's definitely not a personal still even for the most ambitious.

Tell me exactly what you're really trying to build and how you want it to run to make what from what feed and I'll share some resources. I have about every relevant text book and hundreds of journal articles on hand.

You've got some good ballparks, 10-16 kw. But that's also a huge range. The details will depend on the packing, and operating conditions. EG you can feed a lot more power (column load) to something at lower reflux rate than a higher one. Likewise different packings can handle a range of loads and vapor speeds. And if this is really a batch still rather than continuous then gain a lot more flexibility in your controls, but you also need more flexibility in your design as the column will see a wider range of conditions.
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Re: Heating wattage for 6 inch column

Post by LWTCS »

zapata wrote: Fri Oct 23, 2020 6:43 am Not if it's continuous, just needs a little bitty reboiler (or steam injection and no reboiler at all) if it's being run like a traditional rectifying column. And being a rectifying column it's being fed wines, so not much foaming to worry about.

Wizard, is this a made up design? No offense, but it sounds like it is. And will it really be continuous? There is a world of difference, and a fair bit of resources on running continuous stills in batch mode. The fact that you even use the word boiler vs. reboiler makes me think you don't really have any intention of using it continuously. The design, operation and control of the two is very different. Strange as it seems to most of us batch distillers, real continuous distillation is a relatively simple steady state situation so you just have one set of conditions to design for.

And where and what are you feeding it? Liquid at the bottom? Can you possibly get a low abv bottoms waste stream like that if you really run continuous? I think you'll need a mid column feed to not be wasting a lot of alcohol out the bottom, but again, I really doubt this what you are doing. For one, because you'd have run into these problems on the continuous stripping column too. And a 6" D dual column continuous still would need thousands of gallons of wash a day to reach and maintain steady state conditions, that's definitely not a personal still even for the most ambitious.

Tell me exactly what you're really trying to build and how you want it to run to make what from what feed and I'll share some resources. I have about every relevant text book and hundreds of journal articles on hand.

You've got some good ballparks, 10-16 kw. But that's also a huge range. The details will depend on the packing, and operating conditions. EG you can feed a lot more power (column load) to something at lower reflux rate than a higher one. Likewise different packings can handle a range of loads and vapor speeds. And if this is really a batch still rather than continuous then gain a lot more flexibility in your controls, but you also need more flexibility in your design as the column will see a wider range of conditions.
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This is a good post.
The only thing I think needs a bit more context is that on anything 12" or smaller you really can maintain a batch / shift mentality in that A: heat up times are very fast and within minutes the system is producing distillate.
B: a 4" column can easily process 1000-1200 liters of beer in a single shift.
Of course those are smaller commercial volumes but huge (and illegal) hobby volumes. But these volumes are really considered batch volumes for a small craft distillery.

Not sure if I'm making my point? But if designed correctly a 6" beer column can process 150- 200 gallons of beer an hour. So it's nice to be able to process 500 ro 600 gallons in a half day and get home in time for dinner.
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Re: Heating wattage for 6 inch column

Post by Evil Wizard »

Thanks for the great answers. Especially Zapata and LWTCS.
Just a quick reply here as I'm at work (in a distillery).
Yes i suppose it is batch continuous as I'm turning it off at the end of the day, though I do have 44,000L of fermentation capacity.

Yes it's my design. I've made cont strippers in 2 and 3", now 6". Been working at it for years now I'm using it commercially.

And yes, I can often use the wrong term like boiler - reboiler because I am doing my design work in a vacuum except for the fine folks on HD. Here in Canada there are few distillers to talk to and I've yet to meet one that knows anything about cont stills except they maybe bought one and cant get it to work!

So the stripper is taking in 1.6LPM give or take and is putting out 40%-50% abv depending on my CM reflux rate. Distillate heading to the reflux column (not yet built - waiting on parts from china) would be 50C not 95C because I need a lot of that heat from the PC for warming up the incoming wash. I may be able to tweak this once I get new parts.

I intend to feed the reflux column into mid column, 50% @ 50C, though I could potentially pick up waste heat from the stripper bottoms water and get that to 50% @ 70C? (remains to be seen what temp)

Currently my stripper bottoms is 1% abv running on direct steam injection. Once I get the electrician in I'll switch back to internal 220V at 9000w-12000w, I feel like I had lower bottoms losses at that point.

I can stabilize the stripper after about 20L of wash input, I'm not sure I'd need thousands of gallons to stabilize the reflux still (please elaborate), but I will def need very fine control over heating, Reflux condensor temp&flow, VM takeoff sizes and locations.

I concur, foaming and puking is a non issue in the reflux column being fed low wines, and I feel that the reflux column should need less watts than the stripping column since its moving 50% to 90% abv and not 10% to 50%.

Yes, I'm ambitious. And obsessive. Thanks for the input.
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Re: Heating wattage for 6 inch column

Post by ideasinbeer »

Evil Wizard,

I'm curious what you use for packing in the 6" column...
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Re: Heating wattage for 6 inch column

Post by Evil Wizard »

I really like Geolite aka Hydroton. Clay balls, high surface area, size of marbles, full of air pockets and very light and cheap. Used in hydroponics. Been using them for years. The light weight is helpful when you need to lift and assemble a packed column.
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Re: Heating wattage for 6 inch column

Post by zapata »

Sweet! And what's the goal? Vodka? Or just really high proof low wines? In other words how you are going to make "cuts" or not? liquid traps and side draws? Short of doing that (and figuring out placement and draw rate) wouldn't you be better off just running the 2nd column in conventional batch mode?

Keep in mind I'm far more of a student than a practitioner at this level...
I can stabilize the stripper after about 20L of wash input, I'm not sure I'd need thousands of gallons to stabilize the reflux still (please elaborate)
You're right that was an offhand exaggeration on my part, apologies. You should be able to start up the 2nd column in a similar length of time, but you may throw your first column off in the meantime if for example when you start to pump column 2 bottoms back over to column 1 as reflux.
So the stripper is taking in 1.6LPM give or take and is putting out 40%-50% abv depending on my CM reflux rate. Distillate heading to the reflux column (not yet built - waiting on parts from china) would be 50C not 95C because I need a lot of that heat from the PC for warming up the incoming wash. I may be able to tweak this once I get new parts.

I intend to feed the reflux column into mid column, 50% @ 50C, though I could potentially pick up waste heat from the stripper bottoms water and get that to 50% @ 70C? (remains to be seen what temp)
You didn't mention the RC or PC (if separate) for the rectifying column, that's another potential source of heat, but of course it's cooler than the stripper bottoms stream.

It sounds like a great functional continuous stripper, but maybe not the best to integrate into a 2 column continuous setup as is. Ideally you wouldn't be subcooling your strippate at all.
Some questions:
What kind of product condenser do you have that is subcooling the distillate? Can you switch from CM to a total condenser so you can avoid that much subcooling by using liquid management instead? Or a VM takeoff with an overhead condenser so that it doesn't subcool so much? The subcooling is working fine as a stripper, but if you want to feed that into a second column then you just have to immediately undo it. Definitely easier to just not do it than subcooling with wash just to reheat with bottoms. Whatever preheat you lose by not subcooling you can replace by using the 2nd column PC and RC instead.

Or if you really like CM, do you need to condense the strip side at all? Can you feed to the bottom of your 2nd column as a thumper, or will the extra back pressure throw off your wash feed? And of course, it would depend what you're dong with column 2 bottoms....

What are you planning for the bottom stream of the 2nd column? Of course the typical setup is to pump it back to the stripper column as reflux (which will increase your column loading substantially and affect your reflux rate). If you're going to collect it in batch mode for later recycling, that 30L is gonna fill up fast, like in less than an hour, right? (obviously depends on product goal and reflux rate).

How are you preheating the wash feed now? Just through the PC or the dephlag too?
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Re: Heating wattage for 6 inch column

Post by Evil Wizard »

Hey Zapaya, those are more questions than I can easily answer. On many of your questing I'm confused about which column you are talking about.

My setup is rather modular, so yes I can switch things around and preheat different things in different places, and surely I will be doing so. Yes I recognize that cooling the strip distillate at all is unfavourable.
An advantage to doing so is to prevent back pressure from the reflux column into the strip column, forcing alcohol into the strip bottoms.
Running the wash through the reflux side PCs first is great in theory but can lead to cascading temp failures. I won't try that initially. Easier to keep the columns seperate for a while.

Currently i run the wash into the strip pc, an 18" high 6" copper shotgun i made (19*1/2"),raising wash temp to about 80c,then down to the strip bottoms, up through a coil bringing it to 90c, then past an adjustable 1500watt heater bumping it to near boiling, then into a plate above the stripper column boiler where it boils. Then the vapor goes into a short reflux column, sometimes packed, with a tiny dephlagmator, then over into the pc. The deph is 3 turns of 1/4" copper, more of a cold finger. More than that drives ethanol into the bottoms.

The goal? Not needing a huge boiler honestly. If I can do cuts on the reflux side, ideal. If I can just do meths cuts, that's fine. All the fusels fall out of the stripper anyway.

The bottom of my reflux column would be a u shape like my first column. Water falls past the heaters goes sideways and up a short column where its cooled and drops out. I dont see why I'd pump it anywhere, it's just hot water. On the strip side there's lots of it, on the reflux side - far less.
If there is enough alcohol still in it, I'd use it as backset.
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Re: Heating wattage for 6 inch column

Post by LWTCS »

All right here is what I'm doing.

Green piping represents beer feed.
Dark purple represents low wines.
Bright purple represents finished product.
Red represents thumper/ reboiler juice
Gold represents beer column bottoms.
Pink represents heads.

Thumper juice gets pumped back to the beer well to be recirculated back through the system.

LM styled take off ports to allow for heads vapors in suspension to continue toward the top of the spirit column and condensed. At that point heads can be gravity drained (pink piping)to the beer well or collected for later. Without an LM take off port, you cant make any kind of cut.
1603494468931_Over View.png
The top dephlegmator allows heads to pass and bottom dephlegmator keeps tails in the re boiler.

Any opinion or point of view I have is predicated upon this design that is currently in use by several distilleries.

Normally, the thumper does not require additional heat input and only needs to be (automatically) pumped down every 6 hours or so. But that largely depends on RR.
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Re: Heating wattage for 6 inch column

Post by zapata »

Evil Wizard wrote: Fri Oct 23, 2020 2:32 pm If I can do cuts on the reflux side, ideal. If I can just do meths cuts, that's fine.
Assuming you mean methanol, I doubt you'll get any effective separation there, it tracks ethanol pretty well. Are you distilling fruit or something to have enough methanol to worry about? It's pretty much the hardest congener to separate, with the least need to.
All the fusels fall out of the stripper anyway.
Doubt that. You seem to be thinking that distillation separates substances by their pure boiling point rather than their relative volatility. At best some of the fusels are somewhat building up in your stripping column and any that are will eventually build up enough to come over eventually anyway. All fussels are much more volatile than your bottoms stream so they aren't going out there. So a steady stream of low concentration will come over with your 40% while the rest will build up in the stripping column until it crowds ethanol out and eventually comes over in a rush (this happens sometimes even in the giant scotch grain distilleries, and it not only upsets the whole column, but tends to rush right out the top when it happens). Like methanol (and everything really) the other alcohols don't separate by the boiling point of the substances, but by their relative volatility in the mixture, which is driven more by polarity, functional group and mw than bp.
The bottom of my reflux column would be a u shape like my first column. Water falls past the heaters goes sideways and up a short column where its cooled and drops out. I dont see why I'd pump it anywhere, it's just hot water. On the strip side there's lots of it, on the reflux side - far less.
If there is enough alcohol still in it, I'd use it as backset.
Pumping back to the first column is the classic solution going all the way back to the Coffey still. LWTC's solution to periodically recycle it to the wash feed indirectly accomplishes the same thing because that's where the wash goes. As does his option of just running in cycles that allow it to be saved and dealt with later. Note he shows a 200L reboiler and says it needs pumping/draining about every 6 hours (that probably isn't a full 200l capacity, but close enough for hand waving). I had guessed your 30L reboiler would be overflowing in less than an hour.... 200l / 6 hrs = 33.3 lph If his system runs similar flows to yours, yours will be full in just under an hour. I can't really tell from his pic, but if that's a 4" column he's showing, I bet the flows are similar seeing as how he mentioned 1000L wash per shift on 4" in his previous post which is pretty close to your feed rate.

Of course your systems aren't equal, his is a thumper fed with vapor straight from the stripping column while yours is more like running 2 stripping columns in series than a conventional dual column still. There's mathing that could be done to predict performance, but I have a feeling you're going to build it anyway and find out for yourself. That's cool you might learn something to teach everybody. It will be interesting to see how yours behaves at the bottom.

But if you aren't allowing some way to make "cuts", it won't be very interesting to see what comes out of the top of it, it will just be high proof low wines which will need to be re-run in a batch still to make cuts. Continuous distillation isn't a magical process that dumps all the funk down the drain. Side draws and venting the most volatiles are the basic ways to make "cuts" continuously.

Here's a pic to give you an idea where congeners concentrate in a column, and where they must be removed. Note, if you don't remove them, they just build up and come over anyway because a column only has so much holdup. If you don't allow ways to draw them off then as you can see most everything will end up in your final distillate. In which case you could save yourself the trouble of a second column and just make your stripping column a wee bit higher to get the same high proof durty.
coffey congeners.png
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Re: Heating wattage for 6 inch column

Post by LWTCS »

@ Zapata, exellant post again.

Since 6" was the original size reference I posted this system because the spirit column is 6".
The beer column on this one is an 8"

We also pair this spirit column with a 12" beer column that can process 350 gallons of beer an hour. The spirit column can do 32 gallons of finished spirit an hour but does seem to make better whiskey when collecting at 26 gallons an hour.

As Zapata indirectly notes, compatibility or a reliance of either column being perfectly synchronized with each others flow rates is a none issue since the thumper sends back any juice accumulated otherwise created by running high reflux ratios.
We found trying to send thumper juice back to the top of the beer column to be a giant pita because it completely disrupts temps and crashes the beer column. Can do it incrementally with a metering pump but those are spendy and adds a layer of sophistication that may not really make any practical contribution toward measurable efficiency? And then the metering system would have to be calibrated according to each column's flow rates etc, etc.
The system behaves so much better by taking the easy route and sending accumulated spirit column bottoms back to the beer well.

I'm not very smart and am certainly not a chemist, but something happens to tails constituents that is much different when compared to batch stills. My elementary thinking is that something does breakdown or change when tails/bottoms constituents from the thumper are sent back to be recirculated through the system. The additional re exposure to the heat may very well contribute? Similar to how propanol converts to propanoic acid with prolonged exposure to heat.
zapata touches on this on that other thread and promises to build ( and drive) that 3 chamber monster because he must like wrangling wide horses with no rope lol.
I do feel like much (or some) of that tails component does make it's way down the drain in the form of beer column bottoms.
There is also the dilution factor associated with continuous feed too. But my point is I have never tasted tailsy booze off of a continuous outfit.
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Evil Wizard
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Re: Heating wattage for 6 inch column

Post by Evil Wizard »

Wow LWTCS, great to see a diagram. Was that done in Solidworks? I have heard of the program, supposedly it can do temp calculations on heat transfer and other things too.

To elaborate on my goal mentioned earlier, I'd like to offer a small and reasonably priced piece of equipment to craft distillers allowing them to have larger fermenters and smaller kettles. So by removing the REASONABLY neutral spirits and the water from the ferment, we can batch redistill the congeners (heads from the reflux column and tails from stillage from the stripping column) and select for the flavours we want. Then blend these back into the neutralish spirits. This way the size of finishing kettle and the power required to drive it is lessened due to lower volumes. I feel that focusing on making concentrated small batches of congeners is more useful to me as a blender than producing large quantities of slightly flavoured ethanol. Every CEO I've worked for has his eyes on the profit margin and just wants to bring in NGS, sugar it and (artificially) flavour it and sell it. As a craftsman of course this horrifies me. So if I can flavour neutral ethanol (NGS or my own) with specific congeners then I can naturally flavour it to my specs. This also lets me use congeners from completely different ferments. eg I had some 100% wheat wash fermented at 30% with an ale yeast that produced a lot of pear tasting ester (propyl ethanoate or butanoate my guess). The brewer thought he was going to make vodka from this but too hot, wrong yeast. That isolated ester was more valuable blended into a pear brandy and a calvados than was the ethanol recovered from the ferment, which I redistilled with some maris otter in the boiler to make a wheat whisky.

Its all about the congeners, not the ethanol!

Zapata, yes there is a camp that says the fusels come off first and the esters and meths last, and another camp that says the opposite. One is more true for pot stills and the other is more true for properly fractionated reflux columns (this latter point gets confused in several posts I've read).
What both of these stills have in common as opposed to continuous stills such as mine and maybe LWTCS's is that they have higher pressure in the kettle. They assume a closed boiling kettle wherein the pressure can only go up and the temperature rises as ethanol leaves the kettle.

On my still and coincidentally the SOFAC armagnac still at work, the kettle drains out constantly, by height (a liquid lock you might call it). So the max pressure in the kettle, being some combination of the heat input and the vapour above the kettle pushing down by gravity, is limited by the height of liquid in the liquid lock. At this max pressure, the fusels do not seem to get enough push to volatilize themselves off the water molecules, and they fall out of the system. If this is true, I should be able to get more fusels in my stripping column output by lowering the placement of my heaters and raising the height of my water lock. I might try this one day, but when I want fusels, I don't need much and batch refluxing my stillage would isolate those fine.

Thanks guys, this is great!

Back to the original question I guess, LWTCS, what watt range are you using in your 200L reboiler?
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Re: Heating wattage for 6 inch column

Post by Sulaiman »

Regarding heating units in general,
I would use several smaller heaters rather than fewer higher power heaters,
because if a heater fails during a 'continuous' distillation it would be good to have a spare in place,
(or less loss in productivity if no spare)
rather than shut down, drain down, repair, restart.
Only one heater needs control, others could be manually switched.

I like your project, keep us updated.
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Re: Heating wattage for 6 inch column

Post by LWTCS »

The prototype didn't need any re boiler heat per se. But the answer is it depends. I'll explain.
The prototype had a smaller low wines HX and therefore didn't rob too much heat away from the re boiler.
The latest iteration has a larger low wines HX in order to more adequately cope with stripper only mode cooling requirements. Be cause of this less heat is going into the reboiler.
However, this is not a bad thing since re boiler alcohol still flashes.
The depends part depends on the operator's preferred temperature at a couple of locations.

Let's assume your are shooting for a 97C at the top of the beer column. The head temp at the re boiler doesn't have to be 97C . It can be 93C or 92C and will still flash alcohol with no additional heat input. But those temps I'm referring to will absolutely affect the outcome of your spirit profile. So maybe if you prefer the spirit made from the 97C head temp in the reboiler you'll need to throw a bit of heat at the reboiler. Thats what I mean by it depends. Having the ability to throw heat at the re boiler let's you control the final outcome of the finished product better.
This (more heat at the re boiler)btw will also minimize liquid accumulation and therefore require fewer pump downs of the reboiler.
But it doesn't need added heat if you see my meaning?
The ASPEN modeling info I have does not provide me with theoretical heat requirements other than total heat needed. Sorry. But again, the 408 watts per gallon is enough to cover stripping and finished spirits.

Drawing prom is ironcad .

Edit (again): I'm waiting for the temp newbs to blast me for contradicting many earlier statements about temp monitoring lol.
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Re: Heating wattage for 6 inch column

Post by LWTCS »

Here you can see the ASPEN modeling for that configuration.

The circled digits are the temps according to a single target low wines vapor temp.
But you can manipulate ( to some degree) those temp parameters by controlling your beer feed rate.
Screenshot_20180810-131407.jpg
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Re: Heating wattage for 6 inch column

Post by zapata »

Throw those thermometers away and run it by taste! :lolno:
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