Speed of stripping & speed of spirit runs

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skow69
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Re: Speed of stripping & speed of spirit runs

Post by skow69 »

Snowman, these questions only relate to pot stills. If you introduce forced reflux it is no longer applicable.

Googe, I get the impression that you just read the last page or two. Please read the whole thread. I'm sure it will make sense if you start from the beginning. There is no way it could make sense otherwise.
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Re: Speed of stripping & speed of spirit runs

Post by Yummyrum »

Skow I was thinking along the same lines as snowman. Throughout this thread (as I interprete it ) there seems to be no agreement that passive reflux would have any major impact on ABV or separation . I was thinking along similar lines as snowman but using my 2" CM shotty module and connecting it inline with the keg an pot head .

By allowing no refuxing or conciderable reflux to fall back into the pot it would prove the effectiveness or non effectiveness of any reflux in a pot still .
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Re: Speed of stripping & speed of spirit runs

Post by skow69 »

I see where you're going now, I think. You want to test the efficacy of passive reflux by artificially creating a massive amount of it by using a reflux condenser and no packing, right? Sure, that could yield some valuable information. We should agree (I think) that if you demonstrate that lots of artificial-no-packing-reflux doesn't make any difference, compared to a control run, then the entire concept of passive reflux is dead and off the table. If you show that massive artificial-no-packing -reflux can raise the ABV significantly, that only means that it is possible, not that it is occurring. The question of whether passive reflux actually exists in any particular run is still open, right? And der wo will remind us that insulation is a critical control variable, so don't forget about that.

I don't mean to get all anal retentive or bossy about this, but I need some stuff written down in some sort of semi-organized manner just so I can keep track of what the hell we are talking about from page to page. Maybe it's just me, but it seems like the main trunk issue turns out to have a lot of legitimate branches (like passive reflux) that deserve to be in the discussion, as well as some traps and dead ends that just confuse things.

Personally, I don't even have a dog in this race anymore. So much of what I thought I knew turned out to be wrong, and my own trials turned up such unexpected results, that I'm about to start drawing flow charts and truth tables just to figure out what the hell I'm trying to figure out.

Anyway, it's way cool that so many people have found a branch of the puzzle that interests them, and I hope it all converges into some glorious epiphany eventually. Thanks for listening to this rambling crap that's been rattling around in my head.

Can't wait to see what you find out about passive reflux. :thumbup:
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Re: Speed of stripping & speed of spirit runs

Post by Badmotivator »

I've got some data on the passive reflux question.

I was wrong in guessing that the maximum effect of passive reflux would be very very small. It was merely small. :D Another guess was that the maximum effect I could coax out of passive reflux would be very small in comparison to the effect of one plate, and this appears to be true.

Here's another way I was wrong: I thought there would never be a reason to run slowly in a pot still. My new thought is that the advice to run spirit runs slowly does have small value under certain conditions, but holds no general truth. A slow spirit run only makes sense if the combination of power and still geometry (heat loss in the cap and riser) have the effect of a significant reflux ratio. Ironically, it only works to the extent that your pot still is actually behaving like a reflux still.

I started with about 25 gal of TPW wash, which by hydrometer readings was about 9% ABV, divided into 6 equal 4-gallon charges. I ran each charge and took proof measurements at the parrot every 100ml. The first measurement is the reading when the hydrometer first floats in the parrot. I also noted the time. This would be important later for deducing the reflux ratios. More on that if anyone would like.

The runs were:
1) Pot still (insulated) at 4kW. This run establishes the baseline for output speed and proof without reflux.
2) Pot still with huge pipe at 4 kW (reflux ratio is about 0.07)(Heat loss from the pipe was about 264 W)
3) Pot still with huge pipe at 1.4 kW (reflux ratio is about 0.20) (Heat loss from pipe is same as Run 2)
4) One bubble plate (reflux ratio = 1.1)
5) Two bubble plates (reflux ratio = 1)
6) Three bubble plates (reflux ratio = .95)

Here are the proof/sample curves:
6 Run test.jpg
download the higher-quality .pdf version of that same graph
6 Run test.pdf
(31.62 KiB) Downloaded 119 times
.pdf of all data
6 Run Reflux test.pdf
(79.95 KiB) Downloaded 100 times
Next post: pics of the setups.
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Re: Speed of stripping & speed of spirit runs

Post by Badmotivator »

Six charges ready to go:
IMG_1359.jpg
Pot still before insulating:
IMG_1360.jpg
Pot still after insulating many layers thick with dry rags:
IMG_1361.jpg
Pot still with long riser, three clumps of copper mesh in the 24" section. From cabinet top to riser top was 52":
IMG_1368.jpg
Set up for bubble plates (no need to post pics of the two-plate and three-plate set up probably):
IMG_1370 (1).jpg
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Re: Speed of stripping & speed of spirit runs

Post by Yummyrum »

Great work Badmo ...well carried out . I like the comparison to the plated column to put the passive re-flux into perspective :thumbup:
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Re: Speed of stripping & speed of spirit runs

Post by der wo »

Oh I am jeaolous and ashamed. Tomorrow is my experiment and I only have two charges!!! :evil: :oops: :cry: :( :x
No, I am happy, you did such a GREAT experiment. :D :ebiggrin: :D
The differences of the three potstill runs are I think for sure "tasteable" at the foreshots.
The "tall riser" was uninsulated? If so, I thought, there would be more difference between 1 and 2. But the differences between 1 and 3 from 120 to 70 proof are 5-10 proof, that is not nothing.
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Re: Speed of stripping & speed of spirit runs

Post by Badmotivator »

der wo wrote:But the differences between 1 and 3 from 120 to 70 proof are 5-10 proof, that is not nothing.
Not nothing, but I would still advise NOT doing a slow run. First, it took more than three times as long to get that. You could do two fast runs in that time, get better separation, and still have time to get a burger. Second, this was on a low-ABV wash. If your charge was high-ABV low wines you would not see the same delta. Maybe I'll demonstrate that using my low wines from the 6-run test.
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Re: Speed of stripping & speed of spirit runs

Post by der wo »

Badmotivator wrote:
der wo wrote:But the differences between 1 and 3 from 120 to 70 proof are 5-10 proof, that is not nothing.
Not nothing, but I would still advise NOT doing a slow run. First, it took more than three times as long to get that. You could do two fast runs in that time, get better separation, and still have time to get a burger. Second, this was on a low-ABV wash. If your charge was high-ABV low wines you would not see the same delta. Maybe I'll demonstrate that using my low wines from the 6-run test.
You are right. Because this data, there is only a reason to run slow at the beginning and only if I want to toss foreshots.
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Re: Speed of stripping & speed of spirit runs

Post by cranky »

I have been trying not to comment further on this thread but can't help myself.

Badmotivator it would seem you have managed to disprove your assertion that what you consider to be a power myth
Badmotivator wrote:The Power Myth, as I see it,
2) Running slow will increase your ABV
By your own test you showed that this is actually proven to be a fact. It will be interesting to see if you can get higher ABV in a 2nd run by running slower and if so, how much.

Now what about the much more important part of what you consider a myth
Badmotivator wrote: (myth) 3) Running slow reduces smearing, or causes compression of the fractions, or results in a wider hearts cut.
affects smearing of the fractions
Have you or are you going to sample the cuts from those runs and see if there was a reduction in smearing?
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Re: Speed of stripping & speed of spirit runs

Post by Badmotivator »

cranky wrote:I have been trying not to comment further on this thread but can't help myself.

Badmotivator it would seem you have managed to disprove your assertion that what you consider to be a power myth
Badmotivator wrote:The Power Myth, as I see it,
2) Running slow will increase your ABV
By your own test you showed that this is actually proven to be a fact. It will be interesting to see if you can get higher ABV in a 2nd run by running slower and if so, how much.

Now what about the much more important part of what you consider a myth
Badmotivator wrote: (myth) 3) Running slow reduces smearing, or causes compression of the fractions, or results in a wider hearts cut.
affects smearing of the fractions
Have you or are you going to sample the cuts from those runs and see if there was a reduction in smearing?
You're right in a sense. In the real world, there can be an effect from reducing power. By way of explanation, I was focused on how a "pot still" behaves, both in theory and practice. By "pot still", I mean a simple boil & condense with no trickery in between. What I believe I have just demonstrated is that IF running slow rises ABV and reduces smearing, it's because it has raised the reflux ratio to significant levels. And IF the reflux ratio is significant, then "pot still" is a misleading term for what's going on there. If the passive reflux is having an effect, it's a reflux still. I admit that I was wrong about some of my guesses (I guessed a smaller maximum effect from passive reflux, honestly), but I think that that my main assertion is correct and well supported by all of the evidence. A simple pot still with minimal passive reflux will spit out basically the same distillate whether you run it fast or slow on a spirit run. There's an asterisk next to that statement now, which goes: but if you can contrive some significant heat loss from your riser and run it really slowly, you might bump your ABV a little and perhaps take another jar or two as hearts, but it's going to cost you like a 3X difference in run time. I view this as an honest compromise and hope others will as well.

As far as the smearing question goes, I have so far treated as axiomatic that hydrometer measurements are a sufficient proxy for all separations. That is, if I see a steeper hydrometer measurement curve, then all fractions are compressed more, and the hearts are wider. Flatter curve must mean more smearing and narrower hearts cut.

On a personal note, I'm grateful for the opportunity to haggle about this stuff with you and others. My blood boiled a few times and I didn't always keep my cool. I'm sorry for that and I hope to do better in the future. Thanks for participating.
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Re: Speed of stripping & speed of spirit runs

Post by cranky »

Badmotivator wrote: You're right in a sense. In the real world, there can be an effect from reducing power. By way of explanation, I was focused on how a "pot still" behaves, both in theory and practice. By "pot still", I mean a simple boil & condense with no trickery in between. What I believe I have just demonstrated is that IF running slow rises ABV and reduces smearing, it's because it has raised the reflux ratio to significant levels. And IF the reflux ratio is significant, then "pot still" is a misleading term for what's going on there. If the passive reflux is having an effect, it's a reflux still.
If you look at French brandy stills the distillers say the length and shape of the gooseneck are all part of the design to lighten the final spirit so some passive reflux in a pot still is historical. Plus in theory there is no difference between theory and practice but in practice their is. Another issue is heat dissipation, Copper dissipates heat much faster than stainless steel so I would guess there would be more passive reflux from a copper tower Vs a SS one.
Badmotivator wrote: I admit that I was wrong about some of my guesses (I guessed a smaller maximum effect from passive reflux, honestly), but I think that that my main assertion is correct and well supported by all of the evidence. A simple pot still with minimal passive reflux will spit out basically the same distillate whether you run it fast or slow on a spirit run. There's an asterisk next to that statement now, which goes: but if you can contrive some significant heat loss from your riser and run it really slowly, you might bump your ABV a little and perhaps take another jar or two as hearts, but it's going to cost you like a 3X difference in run time. I view this as an honest compromise and hope others will as well.
An extra jar or two of hearts is a significant amount to many of us but I do think more tests are warranted.
Badmotivator wrote:As far as the smearing question goes, I have so far treated as axiomatic that hydrometer measurements are a sufficient proxy for all separations. That is, if I see a steeper hydrometer measurement curve, then all fractions are compressed more, and the hearts are wider. Flatter curve must mean more smearing and narrower hearts cut.
I never judge cuts by ABV, my flute sits on 85-94% from the 2nd jar to 2 or 3 from the last and you never know what might taste good, general advice is always to never use ABV alone for cuts but I do see in your chart what looks to me like an indication that there was compression in the slow run which is why I asked if you blended and sampled. I've gotten to where I do a blend every time I run just to see if I want to keep anything before I rerun it, of course I am now running a flute so it's one run and done or a second run for vodka only. A while back I got a 55 gallon food grade barrel and last week I also got a 30 gallon barrel as well so I am now better equipped to try some of my own experiments in the subject should I somehow miraculously find the time. I doubt I will be able to do much before April but I plan on staring a 50 gallon Cheerios wash soon.
Badmotivator wrote:On a personal note, I'm grateful for the opportunity to haggle about this stuff with you and others. My blood boiled a few times and I didn't always keep my cool. I'm sorry for that and I hope to do better in the future. Thanks for participating.

that's how this hobby, and actually the liquor industry, progresses, we share our ideas, experiment and put them through a sort of peer review process and keep moving forward. The real trick is accepting that we might need to do some things differently so they stand up to peer review, I think we are just about there now. I am often misunderstood by people who then take me the wrong way and get pissed off but we work through that too :D
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Speed of stripping & speed of spirit runs

Post by Badmotivator »

cranky wrote: If you look at French brandy stills the distillers say the length and shape of the gooseneck are all part of the design to lighten the final spirit so some passive reflux in a pot still is historical. Plus in theory there is no difference between theory and practice but in practice their is. Another issue is heat dissipation, Copper dissipates heat much faster than stainless steel so I would guess there would be more passive reflux from a copper tower Vs a SS one.
Does a copper pipe lose more W/m than steel, all other things being equal? Maybe I'm reading these graphs wrong, but I think it's the other way around. (EDIT: Yes, I was reading them wrong. One graph uses difference in C, the other in F. You're right. ) (Second Edit: copper loses about twice the heat as steel.)
heat loss from a steel pipe:
ImageUploadedByTapatalk1454304015.877089.jpg
Heat loss from a copper pipe:
ImageUploadedByTapatalk1454304004.376216.jpg
source: http://www.engineeringtoolbox.com/steel ... -d_53.html" onclick="window.open(this.href);return false;" rel="nofollow
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Re: Speed of stripping & speed of spirit runs

Post by Badmotivator »

I am running an A/B test on 2 X 4 gal low wines charges right now. Deja vu, since it's so similar to a previous test. But this time I am pitting insulated pot still vs. maximal passive reflux ratio pot still on the spirit run. I will record proof and time every 100 ml again, and also try to collect around the hearts region in 100ml jars to try to get a wider hearts cut on the slow run.
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Re: Speed of stripping & speed of spirit runs

Post by der wo »

Here the results of my little experiment:

---Insulated lid vs uninsulated lid---

Two potstill stripping runs of dry fermented and cleared tpw with nutrients, each 12l 12%. Hotplate 1500W.
uninsulated
uninsulated
insulated
insulated
The potstill has a stainless lid and almost no riser. So the effect of passive reflux should be much smaller than at badmotivators trials.

-I notated every 200ml distillate the temp at the highest vapor point. And one measurement after the first 10, 20 and 30ml (to test, if there is a concentration of the foreshots uninsulated).
-the temp gives the current abv here: http://homedistiller.org/theory/theory/strong" onclick="window.open(this.href);return false;" rel="nofollow
-And the abv of the mix after the foreshots. For example at 1000ml I added the 5 200ml-measurements and divided it by 5. That's not a correct calculation, but because I use the same method at both runs, the result is relevant in my opinion.

I am sorry, that I forgot to measure the duration... I know from other runs, that there is a difference, especially at the low power runs I do, when I strip on the grain.

ml-----uninsul.°C--%current--%mix-----insul.°C--%current--%mix
10-------83.6----------78---------------------85.3-------74
20-------87.4----------70---------------------88.1-------68
30-------89.0----------67---------------------89.3-------66
-----------------------------------------------------------------------------
200------90.7----------62--------62----------90.9-------62-------62
400------91.2----------60--------61----------91.3-------60-------61
600------91.7----------58--------60----------91.8-------58-------60
800------92.1----------57--------59----------92.3-------57-------59
1000-----92.7----------55--------58.5-------92.8-------54-------58
1200-----93.1----------53--------57.5-------93.3-------52-------57
1400-----93.7----------51--------56.5-------93.8-------50-------56
1600-----94.2----------48--------55.5-------94.4-------47-------55
1800-----94.8----------45--------54.5-------95.0-------44-------54
2000-----95.4----------41--------53----------95.6-------39------52.5
2200-----95.9----------37--------51.5-------96.1-------36-------51
2400-----96.5----------33--------50----------96.6-------32------49.5
2600-----97.1----------28--------48.5-------97.2-------27------47.5
2800-----97.6----------23--------46.5-------97.7-------22------45.5
3000-----98.1----------19--------44.7-------98.2-------18------43.9

Boring results: Almost no riser -> almost no differences insulated or uninsulated.
Only the foreshots look interesting.
I now have from each run 1 jar with 30ml foreshots and 3 1l-bottles. I will do tastings next two days.
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Re: Speed of stripping & speed of spirit runs

Post by snowman_fs »

Badmotivator, again good work! You have presented great datasets with very visible trends. I applaud and commend your efforts. I also have some still envy after seeing your pictures.

I'm not sure if I can talk about thermodynamics without jacking this thread, but I would caution against using those charts from engineeringtoolbox to draw any conclusions. There are variables left out of the details that can obfuscate the results shown. I'm sure those two charts are from two independent testers where items such as surface condition, pipe orientation and geometry, ambient air movement, ambient radiant energy, altitude/pressure, humidity, pipe wall thickness, test duration, working fluid etc. were not kept constant between the two tests.

The relatively high thermal conductivity of copper compared to stainless steel only helps move heat internally within the metal from a hot spot to a cold spot, it has no significant impact on how the air around the pipe can absorb heat. To move heat away from metal into the air really only relies on the conduction and convection with air. Which is dependent on the properties of air, not the particular metal. Go ahead and use this calculator to see for yourself how little the thermal conductivity of a metal affects the heat loss from a pipe (while leaving all other variables the same). Copper is 230 while stainless steel is 8 BTU/(hr-ft-F) for the thermal conductivity values. http://www.engineersedge.com/heat_trans ... _12921.htm

It is a complicated thermodynamic situation when we start thinking about what happens during a still run and variable materials of construction. Initially, when we are heating up, copper will conduct heat up the vessel wall faster than stainless. But the internal conduction is only significant until steam vapor forms inside the system. The rising steam then functions as a thermal working fluid within the column, depositing on contact the latent heat of vaporization as well as advection. Essentially nullifying any headstart copper had on heat-up as steam can move much faster than conduction, (lookup heat pipes if you wish).

I think the most significant difference between SS and Cu stills are due to simple geometry and heat capacity. When you multiply out the density of Cu and SS to their specific heat capacities there is about 15% more thermal capacity for SS per unit volume. Although SS is typically thinner than copper due to it's increased strength. Any extra capacity to absorb heat based on wall material and/or weight would causes slightly more reflux initially but it would only be a temporary phenomenon until thermal saturation is reached. Any increased surface area of a still would be a long term passive reflux increase. For example 3" nominal Cu = 3.125" OD while 3" nominal SS = 3", resulting in 8% more surface.
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Re: Speed of stripping & speed of spirit runs

Post by Badmotivator »

I think emissivity explains the difference in the heat loss much better than conduction or convection.
http://www.engineeringtoolbox.com/emiss ... d_447.html" onclick="window.open(this.href);return false;" rel="nofollow
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Re: Speed of stripping & speed of spirit runs

Post by snowman_fs »

Emissivity becomes a significant component of heat flow at high temperatures, (glowing red hot) but at low temperatures it is insignificant. Sanitary SS or Cu kept in good condition are both poor emitters/absorbers. The range of emissivity values for SS and Cu are significantly overlapped from the polished condition to oxidized. I don't think we can use emissivity to alter passive reflux in reasonable ways with such variability and negligible magnitude at our operating temperature ranges. I stick by the historic french brandy distillers findings and the influence of simple geometry as being paramount.
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Re: Speed of stripping & speed of spirit runs

Post by damatabr »

Reading the entire post from 1 - page 12 I may have gotten confused and so my comment could be completely irrelevant. I apologize in advance if it is.
In Brazil we only do one run. I never even heard of strip and spirit runs until I got to America.
Anyway, although temperature of the mash is important in that you don't want to rise up to 100 Celsius for us the only thing that was important was vapor temperature.
All we do is control the dephlegmator at the top of the still so as more and more ethanol leaves the mash (making the mix less rich in alcohol) we'd up the temp of the dephlegmator to serve as a way to extend our hearts. No matter how fast or slow we ran our stills, no matter what we did, as long as we kept an eye on the APV coming out of the parrot and the temperature of the dephlegmator we were golden.
I hope this helps in some way.
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Re: Speed of stripping & speed of spirit runs

Post by der wo »

damatabr wrote:All we do is control the dephlegmator at the top of the still so as more and more ethanol leaves the mash (making the mix less rich in alcohol) we'd up the temp of the dephlegmator to serve as a way to extend our hearts. No matter how fast or slow we ran our stills, no matter what we did, as long as we kept an eye on the APV coming out of the parrot and the temperature of the dephlegmator we were golden.
We are talking about potstill speed. It seems complicated enough. When we now start also to consider dephlags, thumpers and reflux stills, we will never clear the fundamental questions.

If there is a difference to run a reflux still with more power and control it to the same abv as with low power, is the overovernext question perhaps.
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Re: Speed of stripping & speed of spirit runs

Post by Badmotivator »

Hey, Der Wo et al. I think we have settled the question of power in a simple "ideal" (non-refluxing) pot still, right? Power doesn't matter in that regime, right? We moved on to examining passive reflux in a pot still in order to determine and quantify the effect, in order to put some refinement to the advice to do spirit runs slowly. I don't want to speak for anyone else, but I am settling on this conclusion:

An ideal pot still will put out the same distillate whether you run it fast or slow. A real world pot still has some passive reflux, ranging from insignificant to small but significant. If your Reflux Ratio (heat loss divided by your heat input) is around .2 or higher you will get noticeably higher initial ABV and separation (though not nearly as much as one plate adds), and slightly wider or better tasting hearts. There is usually a severe time penalty for getting that. A thumper or a plate with active reflux is a far more time-efficient method of widening hearts and shortening run times. The more you chase passive reflux, the more you ought to think about switching to multiple-stage distillation.

For those who have followed the whole investigation, do you think that's a fair assessment of the evidence so far?
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Re: Speed of stripping & speed of spirit runs

Post by der wo »

Badmotivator wrote:An ideal pot still will put out the same distillate (I would say, the same abv) whether you run it fast or slow. A real world pot still has some passive reflux, ranging from insignificant to small but significant. If your Reflux Ratio (heat loss divided by your heat input) is around .2 or higher you will get noticeably higher initial ABV and separation (though not nearly as much as one plate adds), and slightly wider or better tasting hearts. There is usually a severe time penalty for getting that. A thumper or a plate with active reflux is a far more time-efficient method of widening hearts and shortening run times. The more you chase passive reflux, the more you ought to think about switching to multiple-stage distillation.
I think, it's proofed, that for a potstill without passive reflux the power doesn't affect the abv. And an insulated head and riser reduces the passive reflux to almost zero. But we don't know, what is with taste. If there are differences, entrainment could be the reason.
For testing this, aromatic mashes would be better than birdwatchers.

Even a super insulated stillhead will produce some passive reflux at the beginning, because it is colder than the mash. Probably this is the reason, that the first jar is higher in abv than the wash%/vapor°C/vapor%-charts mean. But we can forget about this detail I think, because we didn't see differences in the two runs of your experiment on page 6, I think because this "heating up passive reflux" is not really related to power input.

I am not finished with my tastings, but I can say the first 30ml differ heavily. It looks like there is a good reason to collect foreshots uninsulated and slow. But I am not yet sure about the distillate after the foreshots.
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Re: Speed of stripping & speed of spirit runs

Post by der wo »

Here the tasting results of my experiment:


The first 30ml of the insulated run smell fruity, synthetical sweet fruity. The 30ml of the uninsulated run have more a strong solvent smell.
So the concentration of the foreshots were much better with the uninsulated head.


The first liter after the foreshots
uninsulated: fruity
insulated: fruity, but less, more neutral

The second liter
uninsulated: a bit yeast, smooth, more neutral
insulated: fruity

The third liter
uninsulated: more yeast, bread?
insulated: I don't know, more fruity? a little more neutral?

Conclusion:
The fores are spread over the whole insulated run. Uninsulated the fores are massive in the first 30ml and easy detectable in the first 1/3, but not in the last 2/3 distillate.
About the yeast flavor I think, it starts being detectable, when the fores are gone. So insulated has less yeast flavor, because it's coverd by the fruity flavors.


Mix without foreshots
uninsulated: neutral, the yeast flavor is less than expected. I think the higher abv covers it.
insulated: as expected more heads

Mix with foreshots
uninsulated: dryer, light fruits
insulated: sweeter, dark fruits
But the differences are really little here. Yesterday I found those differences, today it tastes the same.


Conclusion:
If you want to cut foreshots, do it slow and uninsulated. Even with this small riser I got huge differences at the fores concentration. But besides of that there was nothing significantly. Perhaps a fruit or grain mash would be more interesting about the tails.
In this way, imperialism brings catastrophe as a mode of existence back from the periphery of capitalist development to its point of departure. - Rosa Luxemburg
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Re: Speed of stripping & speed of spirit runs

Post by katzgejm »

This thread is BAFFLING to me. one of the first things i experienced running a pot is that less heat in = higher abv at any given point of a run!

if i turn up the heat even very slightly (propane burner), head temp rises and abv drops. reverse is also true. clearly, as more energy enters the boiler, more water (and other compounds) is excited, and joins the party in the column. this makes perfect sense. as a pot of water on the stove heats up, we see steam increase approaching boiling.
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Re: Speed of stripping & speed of spirit runs

Post by der wo »

katzgejm wrote:less heat in = higher abv at any given point of a run...
...depending on the possibility of passive reflux (uninsulated lid and riser).
In this way, imperialism brings catastrophe as a mode of existence back from the periphery of capitalist development to its point of departure. - Rosa Luxemburg
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Re: Speed of stripping & speed of spirit runs

Post by rad14701 »

katzgejm wrote:This thread is BAFFLING to me. one of the first things i experienced running a pot is that less heat in = higher abv at any given point of a run!

if i turn up the heat even very slightly (propane burner), head temp rises and abv drops. reverse is also true. clearly, as more energy enters the boiler, more water (and other compounds) is excited, and joins the party in the column. this makes perfect sense. as a pot of water on the stove heats up, we see steam increase approaching boiling.
This is true but the main goal of doing stripping runs is to remove as much water as possible as quickly as possible... And with flavored spirits this would also carry over more flavor than slowing the take off rate... The %ABV of the low wines isn't considered a factor, speed is... Fast accumulation of enough flavorful low wines for a spirit run is what the whole stripping and spirit run sequence is all about... Yet if the goal is neutral spirits the reflux column will strip that extra flavor from those same low wines...
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Re: Speed of stripping & speed of spirit runs

Post by katzgejm »

rad14701 wrote:
katzgejm wrote:This thread is BAFFLING to me. one of the first things i experienced running a pot is that less heat in = higher abv at any given point of a run!

if i turn up the heat even very slightly (propane burner), head temp rises and abv drops. reverse is also true. clearly, as more energy enters the boiler, more water (and other compounds) is excited, and joins the party in the column. this makes perfect sense. as a pot of water on the stove heats up, we see steam increase approaching boiling.
This is true but the main goal of doing stripping runs is to remove as much water as possible as quickly as possible... And with flavored spirits this would also carry over more flavor than slowing the take off rate... The %ABV of the low wines isn't considered a factor, speed is... Fast accumulation of enough flavorful low wines for a spirit run is what the whole stripping and spirit run sequence is all about... Yet if the goal is neutral spirits the reflux column will strip that extra flavor from those same low wines...
oh yes, noted.

however in a single distillation, i find even a very small fraction too much heat in, my abv drops considerably, and off flavours in the tails smear right into the hearts.

i find i need to run my still at a very slow collection rate, ~500ml/hr, to get good yield and clean distillate.
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Re: Speed of stripping & speed of spirit runs

Post by rad14701 »

katzgejm wrote:
rad14701 wrote:
katzgejm wrote:This thread is BAFFLING to me. one of the first things i experienced running a pot is that less heat in = higher abv at any given point of a run!

if i turn up the heat even very slightly (propane burner), head temp rises and abv drops. reverse is also true. clearly, as more energy enters the boiler, more water (and other compounds) is excited, and joins the party in the column. this makes perfect sense. as a pot of water on the stove heats up, we see steam increase approaching boiling.
This is true but the main goal of doing stripping runs is to remove as much water as possible as quickly as possible... And with flavored spirits this would also carry over more flavor than slowing the take off rate... The %ABV of the low wines isn't considered a factor, speed is... Fast accumulation of enough flavorful low wines for a spirit run is what the whole stripping and spirit run sequence is all about... Yet if the goal is neutral spirits the reflux column will strip that extra flavor from those same low wines...
oh yes, noted.

however in a single distillation, i find even a very small fraction too much heat in, my abv drops considerably, and off flavours in the tails smear right into the hearts.

i find i need to run my still at a very slow collection rate, ~500ml/hr, to get good yield and clean distillate.
Yes, for single runs you want to run low and slow to avoid smearing... But not too slow... Better to run at a rate where blended cuts require no or very little dilution to aging proof of 120 - 130 proof... There is a section on the parent site that covers that for anyone interested, as well as a pot still calculator written by Husker...
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Re: Speed of stripping & speed of spirit runs

Post by katzgejm »

rad14701 wrote:
katzgejm wrote:
rad14701 wrote:
katzgejm wrote:This thread is BAFFLING to me. one of the first things i experienced running a pot is that less heat in = higher abv at any given point of a run!

if i turn up the heat even very slightly (propane burner), head temp rises and abv drops. reverse is also true. clearly, as more energy enters the boiler, more water (and other compounds) is excited, and joins the party in the column. this makes perfect sense. as a pot of water on the stove heats up, we see steam increase approaching boiling.
This is true but the main goal of doing stripping runs is to remove as much water as possible as quickly as possible... And with flavored spirits this would also carry over more flavor than slowing the take off rate... The %ABV of the low wines isn't considered a factor, speed is... Fast accumulation of enough flavorful low wines for a spirit run is what the whole stripping and spirit run sequence is all about... Yet if the goal is neutral spirits the reflux column will strip that extra flavor from those same low wines...
oh yes, noted.

however in a single distillation, i find even a very small fraction too much heat in, my abv drops considerably, and off flavours in the tails smear right into the hearts.

i find i need to run my still at a very slow collection rate, ~500ml/hr, to get good yield and clean distillate.
Yes, for single runs you want to run low and slow to avoid smearing... But not too slow... Better to run at a rate where blended cuts require no or very little dilution to aging proof of 120 - 130 proof... There is a section on the parent site that covers that for anyone interested, as well as a pot still calculator written by Husker...

:thumbup:

i just ran a very tasty little rum single distillation, collected 2.8L @57%abv, 500ml/hr. anything faster than that and i would've had a much smaller, dirtier yield. i think.
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Re: Speed of stripping & speed of spirit runs

Post by skow69 »

How about running some trials and reporting your jar-by-jar results here so we can record them with the rest? Preferably with some sort of control condition for comparison. We desperately need more data. There are several examples earlier in this thread. You could duplicate one of them or modify one so it works better for you. It would be great if we could eventually accumulate enough data to analyse with some statistical confidence. Sort of crowd sourced science for the hobby distiller. I'm afraid anecdotal evidence just doesn't help.
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