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Interest in Continuous Stills?


jheising

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Thanks, I will be following this and anticipating your reports on the project development. Be careful with option 2, a small up front fee to prove comitment might be wise, kind of like a lease with an option to purchase after a predetermined period of time. Good luck, sir.

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Hey Jim, I've been following this thread avidly.

I built a fractional continuous still in high school as a science project for hydrocarbon distillation. We didn't have lovely little Arduinos and Raspberry Pi controllers back then, and my column was difficult to control...I remember having phase problems as temperature rose...with octane coming out of the wrong draw, etc. I am surprised that your still isn't insulated from it's environment. Mine would unbalance if someone opened the door and let cool air in.

I'll be very interested to see the production version. While we are very much involved with batch distilling here at Mother Earth, the utility of having a continuous still producing all the time for such a small investment is very attractive.

I might also say that I liked the look of the "dashboard" on the laptop on your website.

I live in North Carolina, but I am from your neck of the woods (Gulf Islands in BC, actually)...I'd love to come have a looksee next time I'm up to visit my parents...

Dan

Mother Earth Spirits

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Hey Jim, I've been following this thread avidly.

I built a fractional continuous still in high school as a science project for hydrocarbon distillation. We didn't have lovely little Arduinos and Raspberry Pi controllers back then, and my column was difficult to control...I remember having phase problems as temperature rose...with octane coming out of the wrong draw, etc. I am surprised that your still isn't insulated from it's environment. Mine would unbalance if someone opened the door and let cool air in.

I'll be very interested to see the production version. While we are very much involved with batch distilling here at Mother Earth, the utility of having a continuous still producing all the time for such a small investment is very attractive.

I might also say that I liked the look of the "dashboard" on the laptop on your website.

I live in North Carolina, but I am from your neck of the woods (Gulf Islands in BC, actually)...I'd love to come have a looksee next time I'm up to visit my parents...

Dan

Mother Earth Spirits

Dan,

It's really interesting and fun to hear your comments, because those are some of the EXACT same problems we experienced during our R&D. Specifically, the door opening and changing the temperature (and barometric pressure) is an (in)famous story we talk about often! Without giving away too much of our special sauce, there are a number of things we've implemented over the past 3 years that have chipped away at that and other stability issues. Some of them mechanically, but many of them software related.

As for a visit, c'mon by! Just email me at jim@bunkerstills.com and give me a few days notice just to make sure I'm not out of town, and we'll have you on by for a demo and discussion.

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Hey Jake ....How small is your space???... btw I love the stuff going on on your facebook page .... I was stationed in the missile fields of Montana in the early 80s.... Knew Dutton and Conrad well!!!!.....

Well our actual production space is 256 square feet. Not including out "barrel aging area" and the basement area that has boilers and crap shoved in there.

Thanks for checking out our Facebook page, Montana is a great place. Especially for quality spirits, and the beer aint bad either!!

Plus we went with "older looking" German still because we are located in an old train depot. It makes it look more authentic.

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Great thread. Just hope people don't get to comfortable with relying on the automation and leave their facility unattended. Bozo no no. I do feel craft is craft, automation is acceptable but at the end its the $$$$$$$$$$$$ that keeps most going. I think those who do this out of love and challenge will choose wisely. Good luck and look forward to seeing your product in use soon to fairly judge the final product.

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I currently have a continous still I use. It will process up .45 gpm. I designed it and built it my self.

I would put a pic on here but I don't no how to yet.

How much do you think it is worth?

www.dehnerdistillery.com

Great to hear! Would love to see some pictures of it— if you can't get em up, Email them to me at jim@bunkerstills.com and I'll try to get them up. Can you give any more details about how it works?

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Thanks for the detailed reply, but I think we are talking with different vocabulary. Continuous still don't have tails or hearts. To me the tails remain in the stillage on a Continuous. I read your comments as saying your still has two side-draws, One you call hearts is the main spirit draw at 160-190pf and the one you call tails is a second side-draw of less-volatiles at some point below.

I would agree with you if the difference between 190pf and 120pf was only just due to the fusel alcohols in the tails, but in my experience it's usually not.

My comment has nothing to do with fusels per se. There are some 200 flavor congeners in white-dog whiskey and at a minimum some 25 are significant in finished bourbon. If you strip enough of those out in a 161pf product, then you can't legally call it whiskey, or at 160pf you get a gentleman's 75pt from the Whiskey Advocate and Chuck Cowdery points out it lacks conventional bourbon flavor.

Even if you can cheat mother-nature wrt flavor, you can't cheat CFR 27 w/o consequence.

Alternatively if you can't get 190pf+ it's not Vodka or NGS by law.

Yes, at 120pf you may have more tails, but there is usually a lot of water in there as well. With our still there are no plates in the column to add or remove. When we talk about 160-190pf, we're talking about the proof specifically at the point where the hearts are extracted from the still, which is mostly pure ethanol and very little water.

No "usually" about it. Do the math - you are talking 40-% water vs 20-% water at 120pf vs 160pf, but unless you're making Vodka/NGS the goal is not to remove water, that's an added energy cost and carries the risk of flavor loss and you need to dilute to <125pf for barrelling. So your barrels will have around 37% water no matter how you get there.

I appreciate your comments abt adding the 'tails' to the spirit draw for flavor but that opens a lot of new questions abt what exactly is in your 'tails' or why an side-draw at an intermediate location better.

The tails are drawn through an entirely separate draw and can be re-combined with the hearts as they exit the main column to achieve nearly any flavor profile you would with a batch still. What we see is that nearly all the tails come out through the tails draw (with very little water). Essentially, to sum up, you have all the same components (including your tails) to work with, but just much less water

A more conventional continuous whiskey still design would use a single spirits draw, and return any lower-volatiles draw to the beer still (lower plates) either by gravity or pump. Then you can adjust the reflux ratios to get a spirits draw a bit above barrel strength, or higher for a light whisky. I'm just pointing out the difference. I don't really see how a container of 161pf light corn-alcohol and a container of 'tails' (lesser volatiles), maybe including the FAs and bitter fusels gets you to a good product.

Can you adjust the reflux ratio at each side-draw ?

Can you describe the volumes and proofs expected of each of the spirit and lower-volatile draws for say a 100gal @ 8%ABV run ?

Can you explain how you would use these two components and water to create a bourbon white-dog at barrel strength ?

Yes, the 2GPH simply won't be fast enough for some distillers, and our larger models in the future should address that. Although, most people are pretty surprised when they run the numbers. Not sure if you saw the new calculator we put up at http://bunkerstills.com (half-way down the page), but if you put in 8% abv wash, distilled to 120pf and bottled at 40pf you still end up with a production capacity of over 1,000 750ml bottles a week. Not a large scale operation when compared to Jack Daniels, but certainly orders of magnitude more than a craft distillery on a smaller budget can accomplish with batch distillation.

Uhh - no one bottles at 40 proof, but your calculation doesn't make sense. 1 week (168hr) at 2gph and 8% ABV = 26.88gal of AA into the system, but 1000 x 0.75l bottle at 20% ABV = 150 liter AA = 39.66 gal of AA out. You can't increase the amt of ethanol in the still.

Your webpage javascript has an error that makes the diluted output too large by a factor of 1.666 in this example. Here is the correction diff to your webpage javascript. Your numbers are consistently too high

@@ -355,7 +355,7 @@

var distillateABV = parseFloat($("#distillateABV").val());

var finalProof = parseFloat($("#finalProof").val());

var bottleSize = parseFloat($("#bottleSize").val());

- var finalABV = finalProof / 2.0 / 100.0;

+ var finalABV = finalProof/ 2.0;

if(feedABV > 1.0)

{

@@ -369,7 +369,7 @@

var gallonsPerHour = parseFloat((2 * feedABV * 0.9 / distillateABV).toFixed(3));

var gallonsPerWeek = parseFloat((gallonsPerHour * 24 * 7).toFixed(3));

- var gallonsPerWeekFinal = parseFloat((gallonsPerWeek / finalABV).toFixed(3));

+ var gallonsPerWeekFinal = parseFloat((gallonsPerWeek * distallateABV / finalABV).toFixed(3));

var bottlesPerWeek = Math.floor(gallonsPerWeekFinal * 3785.41 / bottleSize);

var casesPerYear = Math.floor(bottlesPerWeek / 12 * 52.1775);

The correct numbers are 610 btl/week @ 40 proof (very weak stuff), or 305 btl/ week @ 80pf.

Yes, almost the entire column is packed. The upper half is packed with copper scrubbies and the bottom half is packed with raschig rings. But again, the basic principle of the still relies more on creating a precise temperature gradient through the still, rather than "plates". You can think of the precise temperature gradient as creating conditions whereby the various types of alcohols are "contained" and refined in the section where they are to be drawn from.

I know well how continuous stills work in theory. The question is what diameter a raschig ring you need to avoid grist blocking the still. I 'm guessing a cm+.

The flow is tightly and automatically controlled with a peristaltic pump. The peristaltic pump is nice because it regulates flow very precisely and tends to be fairly "foul-proof" from solids.

Sounds like a good choice, but I wouldn't expect fouling in a dephlegmator line, and then the constant tubing flex at temps may lead to failure.

There is no insulation, except for a small amount around the heater at the bottom. And yes— controlling the temperature is difficult! We have a pretty sophisticated custom control system which feeds from a number of sensors including temperature and barometric pressure.

This misses the point. Take a household vornado type fan and let it blow on the system once it's in steady state and watch what happens. You should find it drives the system far off the mark despite controls. That d*mned copper is a great conductor both within the system (yeah) and to the environment (hiss).

there is no external condensor that requires water. Since we maintain such precise temperatures at the draw points, the vapor exits the column at just slightly above its condensation temperature. Just a small amount of ambient cooling in the draw tube is enough to bring it back to liquid, well before it reaches the output. Although there is no water required for a condensor, we do require a water source in the beginning to warm up or "wick" the still (although technically you could do it with wash, but it's somewhat wasteful). From the picture on our website, you might see what looks like a condensor on the right side of the still, but it's technically not. We just use that to cool down the distillate (from warm) to room temperature so we can take quick measurements with our hydrometer without having to let it sit.

The Institute of Brewing & Distilling study materials clam that such hot spirits will lose considerable ethanol to evaporation, so they need to be cooled to 30C. Also your system requires that the condensation arms conduct the heat of condensation to the atmosphere and this may mean you have vapor escape on a hot still Arizona day or when operated w/o convection; more than a little dangerous.

I hope you take my comments as intended. You have a really great idea here and I *think* it can use some constructive criticism to make it better.

best wishes,

Steve

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Thanks for the comments Steve. I think perhaps there is just a fundamental hurdle we need to get over with this still, because it doesn't operate like any other continuous still (at least that we know of). Hopefully I can clarify a bit more, and please know I'm not trying to be argumentative at all (except for maybe a couple of points :) ). Splitting up into two posts because the board says I've got too many quotes:

Thanks for the detailed reply, but I think we are talking with different vocabulary. Continuous still don't have tails or hearts. To me the tails remain in the stillage on a Continuous. I read your comments as saying your still has two side-draws, One you call hearts is the main spirit draw at 160-190pf and the one you call tails is a second side-draw of less-volatiles at some point below.

We actually have 3 draws on the side and a 4th one on the bottom for the remaining solids and water. And who says continuous stills don't have tails or hearts? Perhaps calling the draws, "volatiles", "ethanol", "higher alcohols" and "spent wash" would be more technically accurate. We're simply trying to associate them to terms that most distillers will know in order to give a general sense for the stuff is coming out in the individual draws. The same general alcohols and ratios that we call heads, hearts and tails in a traditional batch still are the same general types come that out of the draws of the same name in our still.

My comment has nothing to do with fusels per se. There are some 200 flavor congeners in white-dog whiskey and at a minimum some 25 are significant in finished bourbon. If you strip enough of those out in a 161pf product, then you can't legally call it whiskey, or at 160pf you get a gentleman's 75pt from the Whiskey Advocate and Chuck Cowdery points out it lacks conventional bourbon flavor.

Yes there may be over 200 congeners, but there are really only few that matter in un-aged (notice I didn't say aged) whiskey and most of them are fusels. I'm sure we could spend hours arguing that point, but I've never seen any scientific analysis that says differently. But that is really beside the point. The point I'm trying to make is that the proof of an alcohol has nothing to do with the amount of flavor it contains. It's true that with a traditional batch still you have to leave most of your flavor congeners behind in your tails container or as spent wash if you want your distillate to remain at high proof. But this isn't a traditional still. And who says we're stripping out the congeners? They don't just disappear into thin air. The only place for them to go is out one of the draws, or down the drain. We know they don't come out of the drain because we can measure the ABV of the spent wash coming out of the drain and it's less than 1%. Essentially anything with a boiling point greater than ethanol and lower than water comes out of the "tails"/higher-alcohols draw.

Even if you can cheat mother-nature wrt flavor, you can't cheat CFR 27 w/o consequence.

Alternatively if you can't get 190pf+ it's not Vodka or NGS by law.

We say 160-190pf for exactly those reasons. Our still can reliably produce alcohol in those ranges so that you will be able to legally produce alcohol from whiskey to vodka (and anything in between) as per the TTB requirements. Sure, the still can operate outside of that range, but what is the point? Again, it all revolves around the fact that the proof of the alcohol coming out of the hearts/ethanol draw has nothing to do with the flavor of the end product you can produce. The only reason we even allow you to adjust the proof at the ethanol draw is to be able to fit within the TTB regs. But if you look at it from a technical standpoint, you could make the exact same tasting whiskey with an ethanol draw set to produce 190pf as you could at 160pf— it's all in the amount of tails/higher-alcohols you mix back into it from that draw. Ethanol is ethanol, flavor congeners are flavor congeners, and water is water. The TTB rules were written (and rightfully so) a long time ago with a solid understanding that with traditional distillation methods, whiskey distilled at more than 160pf ceases to really be whiskey and becomes NGS. This isn't traditional distillation and those limitations don't apply, but we're not going to get the TTB to change their rules, so we allow the proof of the hearts output to be adjusted so that when combined with the tails, it fits within the regs.

No "usually" about it. Do the math - you are talking 40-% water vs 20-% water at 120pf vs 160pf. So your barrels will have around 37% water no matter how you get there.

In the most respectful way; you're just completely wrong on this point. Proof and ABV as defined by any instrument a distiller would ever use to measure it, is based on the specific gravity of Ethanol. Not all alcohols. Not "everything but water". Just Ethanol, period. Higher concentrations of methanol, other alcohols (including fusel), or anything else for that matter can change the proof of your alcohol. Yes water is a big one one, but certainly not the only one.

I appreciate your comments abt adding the 'tails' to the spirit draw for flavor but that opens a lot of new questions abt what exactly is in your 'tails' or why an side-draw at an intermediate location better.

It's really simple, the tails are everything that has a boiling point above ethanol and below water. Same as in a batch still if you make your cuts based on temperature.

A more conventional continuous whiskey still design would use a single spirits draw, and return any lower-volatiles draw to the beer still (lower plates) either by gravity or pump. Then you can adjust the reflux ratios to get a spirits draw a bit above barrel strength, or higher for a light whisky. I'm just pointing out the difference. I don't really see how a container of 161pf light corn-alcohol and a container of 'tails' (lesser volatiles), maybe including the FAs and bitter fusels gets you to a good product.

This is not a traditional continuous whiskey still.

Can you adjust the reflux ratio at each side-draw ?

The reflux at the "heads" and "hearts" draw is set to a fixed ratio, and the "tails" is adjustable. The tails is really the only one that needs to be adjustable because it has the same effect all the way up. Closing it off "pushes" more of the tails into the upper sections so you can start to see more "tails" in your ethanol draw if you want. Opening it up allows for a sharper cut-off between the two.

Can you describe the volumes and proofs expected of each of the spirit and lower-volatile draws for say a 100gal @ 8%ABV run ?

Sure, but it could change quite a bit depending on the compounds in your wash, so any one number would be wrong. But I think there is a much simpler way to look at it:

Heads: Anything in your wash with a boiling point of less than 173.1F.

Hearts: Anything in your wash with a boiling point at or around 173.1F.

Tails: Anything in your wash with a boiling point of greater than 173.1F and less than the (barometric pressure adjusted) boiling point of water.

Drain: Anything in your wash with a boiling point of water or above.

Uhh - no one bottles at 40 proof

Yes, my mistake. I was pasting in from another calculation I was doing for liqueur and didn't catch the error. Thanks for the catch.

--- Continue to next post ---

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but your calculation doesn't make sense. 1 week (168hr) at 2gph and 8% ABV = 26.88gal of AA into the system, but 1000 x 0.75l bottle at 20% ABV = 150 liter AA = 39.66 gal of AA out. You can't increase the amt of ethanol in the still.

Your webpage javascript has an error that makes the diluted output too large by a factor of 1.666 in this example. Here is the correction diff to your webpage javascript. Your numbers are consistently too high

The correct numbers are 610 btl/week @ 40 proof (very weak stuff), or 305 btl/ week @ 80pf.

See below.

- var finalABV = finalProof / 2.0 / 100.0;

+ var finalABV = finalProof/ 2.0;

Why would I not divide by 100? ABV is a percentage.

- var gallonsPerWeekFinal = parseFloat((gallonsPerWeek / finalABV).toFixed(3));

+ var gallonsPerWeekFinal = parseFloat((gallonsPerWeek * distallateABV / finalABV).toFixed(3));

Ahh. You're right, and thanks for the catch. At the higher distillate proofs I was using for testing the calculator, the differences aren't that big, but at lower ones, it does make a bit of difference. I made the update on the website.

I know well how continuous stills work in theory. The question is what diameter a raschig ring you need to avoid grist blocking the still. I 'm guessing a cm+.

Why would you ever allow grist to enter the still? It's easy enough to filter out before it even gets there. We filter out any large solids that would clog up the copper tubing or raschig rings with a simple re-usable filter and baffle before it even gets into the still.

Sounds like a good choice, but I wouldn't expect fouling in a dephlegmator line, and then the constant tubing flex at temps may lead to failure.

The pump only operates with liquid at room temperature since it pumps from the wash holding tank into the still. With the proper tensioning and materials, peristaltic pumps can have tremendous lifetimes without tubing failure. We figure tubing is easy to replace on a regular basis (if you're worried about it), when compared to the downtime of having to fix a seize or unclog a traditional pump.

This misses the point. Take a household vornado type fan and let it blow on the system once it's in steady state and watch what happens. You should find it drives the system far off the mark despite controls. That d*mned copper is a great conductor both within the system (yeah) and to the environment (hiss).

What point? It either works or it doesn't. In our understanding of the physics behind the still, adding insulation would actually prevent it from working. But you're right— small external temperature changes can be a common problem, but we've spent a lot of time addressing problems like this, and our solution doesn't require external insulation. Again, this thing is not based on the Coffey or any other continuous still design we know of. It's entirely new.

The Institute of Brewing & Distilling study materials clam that such hot spirits will lose considerable ethanol to evaporation, so they need to be cooled to 30C. Also your system requires that the condensation arms conduct the heat of condensation to the atmosphere and this may mean you have vapor escape on a hot still Arizona day or when operated w/o convection; more than a little dangerous.

Sure, you can lose ethanol to evaporation by leaving any container open on a hot day. If our customers want an external chiller to bring it from slightly above room temperature to room temperature, we'll be happy to offer one. But with the low flow rates we're taking about here, it's just never been a problem, and we just don't see much reason to add to the cost of the system for something that hasn't been entirely necessary in our daily use. As we move up into larger flow units in the future, I'm sure we'll more than likely want to offer an external chiller to help cut down on evaporation.

I hope you take my comments as intended. You have a really great idea here and I *think* it can use some constructive criticism to make it better.

Absolutely appreciate the comments, and please take my responses as intended as well! We will certainly always be learning, and our customers and the community at large will play a huge part in that— so our ears are always open. Although I will push back on one little thing— that you might view this as just an "idea". While I'm sure there is tons of room for improvement, we've used this still to produce 100% of our products for over 3 years now, and we know that it works quite well for us. We could easily keep the wraps on it for ourselves and call it a competitive differentiator, but we really believe distilleries should be competing on the merits of their business style and the taste and quality of their products, not on how much alcohol they can produce in a single day on a batch still. So while I'm sure there are a million things we have yet to learn, we do know one thing— it works well enough to produce award winning spirits that have satisfied thousands of customers from all over the world. And I think and hope that's a good place to start.

Keep up the great discussion folks!

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Thanks for the comments Steve. I think perhaps there is just a fundamental hurdle we need to get over with this still, because it doesn't operate like any other continuous still (at least that we know of).

...

We actually have 3 draws on the side and a 4th one on the bottom for the remaining solids and water.

Your still operates like every other fractionating still. I suggest you invest in a good ChemE book on mass transfer and save yourselves a lot of wheel re-invention. It seems you have a vapor phase "top" (called heads, but never foreshots), 2 equilibrium side draws, and liqiuid stillage.

Yes there may be over 200 congeners, but there are really only few that matter in un-aged (notice I didn't say aged) whiskey and most of them are fusels. I'm sure we could spend hours arguing that point, but I've never seen any scientific analysis that says differently.

Wow - did you really say that ? If the stuff off the still merely differed by fusels, then the characteristic flavors of rum, rye, wheat, corn, brandy would be indistinguishable!! Fusels are the direct result of yeast genetics and fermentation conditions, not the wash media per se. Even the dullest tongue knows that grist and yeast (isoprenoids and esters amongst others) contribute significantly to flavor.

Some of the basic textbooks cover the creation of esters, damascone, acids etc, but examine ....

AROMA CHARACTERIZATION OF AMERICAN RYE WHISKEY BY CHEMICAL AND SENSORY ASSAYS - Lahne

Analysis by gas chromatography/mass spectrometry of fatty acids and esters in alcoholic beverages and tobaccos - Ng

Flavour Components of Whiskey, I. Distribution ... - MacNamera, van Wyk, et al

Characterization of the Most Odor‐Active Compounds in an American Bourbon Whisky by Application of the Aroma Extract Dilution Analysis - Poisson, Schieberle

Origins of Flavour in Whiskies and a Revised Flavour Wheel: a Review - Richardson

That just scratches the surface.

But that is really beside the point. The point I'm trying to make is that the proof of an alcohol has nothing to do with the amount of flavor it contains.

That's technically true *IF* you could add the flavor components to pure ethanol at a fraction of 1%; but it's very very wrong if you are separating in a column with a limited number of plates. I suggest you examine "Whisky Technology, Production and Marketing" graphs 6.10 & 6.12 & 6.13. Or "The Sci and Tech of Whiskies" figs 6.1,6.2,6.3 and then get a ChemE to review your understanding of the basics as they apply to a still.

flavor congeners are flavor congeners,

No. We want some congeners and not others, but separation without a hundred plates is a trick.

The TTB rules were written (and rightfully so) a long time ago with a solid understanding that with traditional distillation methods, whiskey distilled at more than 160pf ceases to really be whiskey and becomes NGS.

Funny thing - the laws of physical chemistry haven't changed since that law was written in 1968, long after continuous was the std for large commercial distillers.

In the most respectful way; you're just completely wrong on this point. Proof and ABV as defined by any instrument a distiller would ever use to measure it, is based on the specific gravity of Ethanol. Not all alcohols. Not "everything but water". Just Ethanol, period. Higher concentrations of methanol, other alcohols (including fusel), or anything else for that matter can change the proof of your alcohol. Yes water is a big one one, but certainly not the only one.

A finished white-dog there may be around 1/3rd of 1% fusels and about 0.1% other stuff, the rest is water and ethanol only. Even in your tails fraction the fusels are a tiny minority of the volume (maybe several percent). So your 160-190pf spirit-draw cannot differ from pure EtOH+H2O by even 1% (which is exacly why I wrote "20-%" water, a little less that 20%).. Your other error in thinking is to even mention methanol. There is virtually no methanol any grain fermentation.

This is not a traditional continuous whiskey still.

I'll be sure to call Vendome in the morning and tell them that some guy designing his first still says the continuous whiskey still specs they sent me are all wrong ;^)

The reflux at the "heads" and "hearts" draw is set to a fixed ratio, and the "tails" is adjustable. The tails is really the only one that needs to be adjustable because it has the same effect all the way up. Closing it off "pushes" more of the tails into the upper sections so you can start to see more "tails" in your ethanol draw if you want. Opening it up allows for a sharper cut-off between the two.

Quiz. Increasing the reflux ratio (a) increases or (B) decreases the separation ?

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Hey Steve, I'd be happy to move this over to a new topic called "Distillation Death-Match" if you want to go toe-to-toe with me on these arguments that have strayed from the topic of continuous distillation— I love a heated debate (according to my wife) :rolleyes: . But this appears to be turning into a pissing match, and probably not really valuable to anyone else on this thread.

I'll just end our discussion with this: we've built a continuous still that has been used for quite some time now to make whiskey and NGS that many people consider quite good, and it didn't cost us tens or hundreds of thousands of dollars to build, operate and maintain. The proof, as they say, will be in the pudding (or alcohol in this case), and we'll let the market decide if and how it works. Fair?

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Hey Steve, I'd be happy to move this over to a new topic called "Distillation Death-Match" if you want to go toe-to-toe with me on these arguments that have strayed from the topic of continuous distillation— I love a heated debate (according to my wife) :rolleyes: . But this appears to be turning into a pissing match, and probably not really valuable to anyone else on this thread.

I'll just end our discussion with this: we've built a continuous still that has been used for quite some time now to make whiskey and NGS that many people consider quite good, and it didn't cost us tens or hundreds of thousands of dollars to build, operate and maintain. The proof, as they say, will be in the pudding (or alcohol in this case), and we'll let the market decide if and how it works. Fair?

I don't see that it's strayed. You are making assertions about your system and I've rebutted some. But it's clear we're not speaking the same language nor sharing a common understanding of issues like the basic operation of continuous stills. Anyway instead or getting straight responses you are objecting to the basics like that white-dog is >99% Water+EtOH, or that passive condensers are fundamentally unsafe unless the environment is controlled.

So be it..

Sincere best wishes Jim, and I do wish you every success.

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Dang, i was sort of enjoying that.

Natrat,

LOL :D . Okay, consider me suckered in. I'm just shaking my head and laughing as I write this, because I should know better. But here goes.

Steve,

First off. Do you actually own or operate a distillery? Have you ever operated a continuous still? You seem to have a lot of books and papers handy and ready to cite, but I've yet to see you mention any real-world, hands-on experience. Perhaps you do, but it's just not clear from your profile. I'd just like to know who I'm dealing with. I'm new here, so perhaps I don't understand the clout that you may have. If you want my credentials, they're simple and probably not all that impressive. I co-own a small, but successful distillery with my family that we started in 2010. We've designed and built a still that isn't based on any design we know of, and it solves a heck of a lot of problems that we've faced (as do many other craft distilleries).

I suggest you invest in a good ChemE book on mass transfer and save yourselves a lot of wheel re-invention.

Reinvention of what? A continuous still that is cheap and easy to operate? I'm pretty sure that's the whole point, and I think we're okay with that. If we could have afforded a traditional continuous still, we'd have just bought one for our distillery a long time ago and saved ourselves the trouble.

Some of the basic textbooks cover the creation of esters, damascone, acids etc, but examine ....

AROMA CHARACTERIZATION OF AMERICAN RYE WHISKEY BY CHEMICAL AND SENSORY ASSAYS - Lahne

Analysis by gas chromatography/mass spectrometry of fatty acids and esters in alcoholic beverages and tobaccos - Ng

Flavour Components of Whiskey, I. Distribution ... - MacNamera, van Wyk, et al

Characterization of the Most Odor‐Active Compounds in an American Bourbon Whisky by Application of the Aroma Extract Dilution Analysis - Poisson, Schieberle

Origins of Flavour in Whiskies and a Revised Flavour Wheel: a Review - Richardson

Have you actually even read any of these? I'm not sure you have, because If you had, you'd realize they disagree with you. I actually have read many of these. For example, let's take one of your first ones, "AROMA CHARACTERIZATION OF AMERICAN RYE WHISKEY BY CHEMICAL AND SENSORY ASSAYS".

On page 1:

…with no‐one odorant responsible for its characteristic aroma, but among the

key aroma compounds identified were: 3‐methyl‐1‐butanol, 2‐phenylethanol, cis‐(3S,4S)‐whiskey

lactone, guaiacol,syringol, and vanillin. These compounds likely mainly originated from either yeast

metabolism(in the case of fusel alcohols) or lignin pyrrolysis

On page 11:

It is now known that

much of the characteristic flavor and aroma of American whiskey comes from the distillate’s long

contact with charred oak (10‐12)

On page 12-13:

The advent of GC allowed for far more precise identification of minor constituents in whiskeys.

By the early 1960s, a huge number of volatile compounds in whiskeys were being identified by a number

of research groups(18‐26). Unfortunately,most of these studies, while interesting from the standpoint

of analytical chemistry and extraction and isolation science,mostly catalogued compounds,rather than

considering their importance. Many of them,for example, identified compounds hitherto unidentified

in whiskeys(and sometimes in nature)(22), but were unable to determine whether these compounds

made any important contribution to whiskey aroma.

On page 13:

It is well‐known that the barrel used for maturing whiskey contributes much of the whiskey’s

flavor(15) –most, in the case of American whiskeys(5). Many of the important odorant classes in

whiskey, especially lactonic and phenolic compounds, are extracted from wood during the maturation of

the whiskey (32).

It goes on and on. And please, don't put words into my mouth. I've never once said that aged whiskey doesn't have hundreds of flavor congeners (in fact I made it a point to clearly state that I was not referring to aged). I've simply stated that when it comes to un-aged whiskey as it comes out the still, the number is far less, and that the majority of them are fusel alcohols.

No. We want some congeners and not others, but separation without a hundred plates is a trick.

So you're saying that the only way to make good whiskey is with a still that has a hundred plates that can separate good and bad congeners? Good to know. Make sure you let everyone else know that it's impossible to make good whiskey in a pot still.

Your other error in thinking is to even mention methanol. There is virtually no methanol any grain fermentation.

Not sure where you're getting that from. Have a look at http://what-when-how...gener-analysis/ at "Table 2 Congener content (mg I 1) of alcoholic beverages". Sure, US whiskey doesn't have a lot of methanol compared to say, plum brandy, but it looks to me that it can contain as much as some wine brandy. But again, I'm not sure what this has to do with continuous distillation in particular, other than you trying to sound smarter than me.

I'll be sure to call Vendome in the morning and tell them that some guy designing his first still says the continuous whiskey still specs they sent me are all wrong ;^)

To clarify, when I said "This is not a traditional continuous whiskey still.", I meant, "Ours is not a traditional continuous whiskey still".

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Now the the next post:

I don't see that it's strayed. You are making assertions about your system and I've rebutted some.

What have you rebutted? Other than my website calculator having a bug (and I sincerely thank you for catching that), what assertions have I made about our system that you've rebutted? You've rebutted nothing other than the fact that you claim to know more about our still than we do. If you're saying you know more about traditional continuous distillation, then congratulations! You win. All I know about traditional continuous distillation is from what I can read, and that it was far too expensive and complex for us. So we took a different approach. Please feel free to purchase and operate a traditional continuous still if you can afford one, because it sounds like you'd know exactly what to do with it. We'll work with the others who have looked at purchasing a traditional continuous still and found them to be too complex and too expensive.

But it's clear we're not speaking the same language nor sharing a common understanding of issues like the basic operation of continuous stills.

Basic operation of what continuous still? Yes, we're not sharing the common understanding of the basic operation of continuous stills, because you are not familiar with the basic operation of OUR continuous still. Don't claim to be an expert in a system you've never even laid eyes on, because you are not.

Anyway instead or getting straight responses

I'm not giving straight responses, or not giving the responses that you want to hear?

you are objecting to the basics like that white-dog is >99% Water+EtOH

Where have I said that? No need to put words into my mouth.

, or that passive condensers are fundamentally unsafe unless the environment is controlled.

Again, no need to put words into my mouth. Sure, passive condensers may very well be unsafe with some stills— so is holding a lit match over an opened container of high proof ethanol. I'll say it again, in OUR still we have not found that it is a requirement. If the customers who USE our still feel that it is a concern, we will certainly address it. We haven't blown ourselves up in the 3 years we've been using it, and have operated in a very safe environment.

Anyway, I'm starting to smell a bit of troll bait, so it's probably time for me to really shut up this time, and get back to work. :rolleyes:

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I just want to put in my $0.02 regarding a great interest in the continuation of this discussion. It has gotten a bit heated, and perhaps that's unavoidable, but I hope it can continue with more light than heat.

Jim, you've mentioned several times that your still is different from other continuous stills. Can you perhaps characterize the differences in a bit more detail? You've mentioned the 4 draw points, but my reading into continuous distillation suggests that multiple draw points is the norm for continuous fractional distillation. Another point of differentiation might be your software control system, but again, commercial systems have complex control systems as well. Photos of control rooms in large distilleries often show the operator in front of several computer monitors showing a graphic representation of the system along with realtime data monitoring and logging.

Steve, in your introductory post from last December, you describe yourself as a "noob" with a "dream" of opening a distillery. Knowing how long it takes to go from dream to reality, I suspect you're still in the idea phase. I think Jim's question regarding your actual experience is fair, and perhaps you can elaborate on any actual experience with continuous distillation.

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Jedd,

Thanks for interjecting and bringing some clarity back to the discussion. Specifically to your questions about differentiation, I wasn't necessarily trying to argue with Steve about the number of draws in our still being a differentiator. I was primarily objecting to Steve's constant assertions that because he thinks he understands how traditional continuous distillation worked, that it automatically made him an expert on how our continuous still worked. Not to mention, it was extremely hard to follow exactly what he even thinks a continuous still is. For example, in one earlier post:

A more conventional continuous whiskey still design would use a single spirits draw, and return any lower-volatiles draw to the beer still (lower plates) either by gravity or pump.

Here he mentions a single spirits draw and returning lower-volatiles to beer plates. Our still doesn't have plates, or a single draw. So if that is his definition of a conventional continuous whiskey still, then by his definition, we are not a conventional continuous whiskey still.

Another example:

It seems you have a vapor phase "top" (called heads, but never foreshots), 2 equilibrium side draws, and liqiuid stillage.

I can't even decipher what he means here. Vapor phase "top"? There is vapor throughout most of still, not just the top. In a previous post, he said I couldn't call it heads, but now he says it is heads. 2 equilibrium side draws? Liqiuid stillage? I have no ideas what those terms even represent in this context. Does anyone else? So all I can say to that is that our still is quite a bit different than how he is describing what he thinks it is (or at least what I can decipher he thinks it is).

There are probably a few "real" technical differentiators that we might go into, like we don't require live steam, and that no part of the still goes above the boiling point of water, etc. But I'm not sure those really matter, or that anyone should care about it. I think when it really comes down to it, the only differentiators that really matter are simply that we have a continuous still that:

1) Can be used to make good NGS and whiskey.

2) Can be operated without constant babysitting.

3) Is affordable to even the smallest craft/artisan distillers.

Perhaps the lesson learned is that it's best to just let those differentiators stand the test on their own, without going into the minute technical details on how we make each of those possible. Thanks again Jedd for the clear and concise response, and hope that answers your questions.

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A continous still is just that, " continous". It does not matter how many ports there are. Just look at a oil refinery. They make all kinds of products out of crude oil with one continous still, and a crap ton of ports.

For me I have two three ports, one in, and two out. For me it is super complex in design but super simple to operate.

To each his own. As far as equipment goes.

Just as when pot stills were the only thing, then along came refraction stills. I'm sure they were looked at funny. Now continuous stills are getting a bad rep, or a miss under standing. It is only a matter of time before the masses come around.

Super easy to use! Like I said. As a good piece of equipment should be.

Thanks

Joseph

Master Distiller

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I was curious about your study on relative operational costs of steam (gas fired) vs electric.

Steam, while weighted heavy on first cost, is more efficient energy wise, no?

If small set-ups are more efficient with electric, what is the top over point where steam is more efficient.

I would assume also, some outfits would be located where enough electric power may not be available, all those in "agricultural zoned" permits, more than likely.

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any direct heat will be more efficient then the same heat source with an intermediary step like steam, but there are always trade offs.

with steam its easier to do consistent heating, so you lose in efficiency and gain in ease of use.

now steam gets really interesting when doing things like steam injection, which seems to be standard practice for the large commercial distilleries continuous columns. You can do things with steam that are just not practical with direct heating methods.

now as a heat source gas is usually the least expensive option in cost per Btu, so it is the usual go to for heating water to steam.

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Agree with Artisan. A couple more points:

1. It sort of depends on what you mean by "steam". As Artisan points out, there is steam jacketing and steam injection. Steam jacketing in a batch still is common practice, and in my opinion is an excellent way to go. Jacketing can be done very safely and easily because it's usually a fully self-contained system. But when we talk about steam in traditional continuous distillation, we're probably referring to the injection or "live" steam type. Specifically if you're talking about a traditional Coffey still design. Live steam injection tends to be way more complex and expensive since you're typically injecting steam from a high pressure vessel directly into the column. It requires expensive plumbing and safety mechanisms since it's essentially "open" to the environment. So specifically to your question, when talking about live steam injection, the top over point is quite high and is one of the primary reasons continuous stills are typically so expensive.

2. In our still we use an industrial electric jacket heater which wraps around the column at the base. Essentially the heating element is ceramic, covers a large surface area and never comes in contact with any liquid. It heats in much the same way a steam jacket would.

3. In terms of cost per BTU of gas vs. electricity— I think it really depends on what part of the country you live in. For example, here in the Northwest electricity is so darn cheap, it's hard to beat. But in the rest of the country it may not be that clear-cut.

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It is an understatement saying cost of electricity MAY not be as cheap in other parts of the country (world).

Not only the cost of the electricity is important, but whether the distillery can physically install enough amperage and voltage.

The last part cuts off many distillers right at the knees before they get started.

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