Speed of stripping & speed of spirit runs

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cranky
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Re: Speed of stripping & speed of spirit runs

Post by cranky »

I was thinking about taking this task up. My little pot needs some cleaning runs to get it ready to run my blackberry and I have 3 quarts of pretty high ABV stuff waiting to be used for just cleaning. So I was thinking as long as I am going to be cleaning it anyway, I might as well go ahead and install that 5500W element and run a few tests. I figure I can water the cleaning alc down, do 3 runs running it slow, med and high and pour the collected distillate back into the boiler after each run to bring the solution back to what it started at, or at least close so I am comparing apples to apples. Collect in 100ml increments, or as small as I can and still get a reading and see what the difference is. Not saying it will be anything in particular or conclusive because each still is different but maybe it will tell us something in regards to the so called myth #2
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Re: Speed of stripping & speed of spirit runs

Post by raketemensch »

I've been digging pretty deeply into the forums the past couple of days, as usual coming back out reeling and stumbling...

A lot of it is too much to learn in too little time, and the rest of it is contradictory information. Every time I think I've learned something, I find a solid argument against it.

Anyway, I've also been reading through a ton of MashRookie's threads, and stumbled onto this Usge post, which I think pertains to this discussion:

http://homedistiller.org/forum/viewtopi ... 6#p6925717
Usge wrote:You have to remember that there's heating/cooling going on inside the column separately from what's going on in your boiler. The reason your column can maintain a given vapor temp or equillibrium is because there is cooler, lower boiling point compounds at the top that are being replaced as they are taken off. As the alc is depleted towards the end of the run, the temp gradient is going to rise and it eventually will destabilize and "squash" that "reservoir" zone near the take off and the compound with a lower boiling point that was once there, and maintained, will be replace with one that has a higher boiling point. On straight up fractioning tube (with no reflux condenser), the only way to control this is by "heat"/vapor speed vs take off rate. In other words...you have to run it SLOW. Perhaps stripped of all the other complexity, these factors can offer some insight.
And a bit from MR himself from the same thread (the whole thing is definitely worth a read):
MashRookie wrote:But, I think the one thing that stuck out to me in my research on "smearing" issues....and take off speeds, etc., was that there is a pocket right near the take off that needs to be stable. The vapor speed going up, and the amount taken off, vs what is returned...forms a stable area/pocket for drawing off. If you draw off too fast...you "pull" the lower volatiles up quicky...squash this sweet spot..and smear the vapor. You are then just pulling what comes off the pot up the tube. If you balance everything right...the idea is that what is coming off, is replaced in such a way by lighter portions coming up through the column to maintain this pocket in a stable way..ie stabilizing the column.
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Re: Speed of stripping & speed of spirit runs

Post by skow69 »

Good man, cranky. More data from more trials is the only way we can smooth out issues like the difference between stills.

Raketemensch, we need to restrict this discussion to potstills. When you introduce reflux, then speed and temperature take on completely different roles.
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Re: Speed of stripping & speed of spirit runs

Post by cranky »

skow69 wrote:More data from more trials is the only way we can smooth out issues like the difference between stills.
That's true, The problem now is I broke yet another test cylinder :roll: This is the 3rd one in as many months. I went 3 years before my cat broke the first one and the new replacements are way thinner glass and break way too easy. I'm thinking about just using a 3/4" copper tube from now on or grinding down the broken end on the newest glass one and fitting it to a short copper tube. It is almost a perfect fit over a 1" copper tube, I figure a cap on one end fastened to a base of some kind and a few wraps of PTFE tape and I can probably get it to seal and still use it. Life is getting in the way of playing right now though so I don't know when I will get to some type of testing.
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Re: Speed of stripping & speed of spirit runs

Post by ShineRunner »

I know I'm kind of late to the party here, but I read through the past pages and am intrigued by this. I'm about to do a stripping run tomorrow and then spirit run some time in the near future. What, if any, data can I try to collect?

A little background on my setup. I am working on upgrading to a keg with liebig right now, but currently have a 15.5 gal keg with upside down bowl running directly into 1/2" tubing, which runs to a worm in a bucket. It's low tech, but it's gotten me through several gallons. Not sure how useful that setup would be, but I'd like to help out this discussion in any way possible.

Edit: the controller is a PWM setup carried over from brewing. I know it's not ideal, but it cycles at least every second so I don't think there's any smearing from it. Haven't noticed it on previous runs anyways. I couldn't measure wattage, but could roughly figure it out from the duty cycle

For the spirit run, I'll probably have about 8 gallons of 30% low wines from Jimbo's bourbon to run. Not sure that I could do 2 separate runs since my element is about at the 3 gallon line. I could run it fast and check abv and then re run everything again, but that wouldn't help for cuts/smearing.

Any guidance?
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Re: Speed of stripping & speed of spirit runs

Post by Badmotivator »

I'm not trying to rekindle flames that have died out, but... the idea that cycling power causes smearing is another BS retread of the Power Myth. :)

Cool that you are motivated to contribute to this inquiry. Thanks. Any careful A-B type test, controlling for variables other than power, would be interesting and potentially useful. Even a faulty test may help us to think more precisely about what constitutes a faultless test. It sounds like it'd be hard for you to do an A-B thing right now though, which we can all relate to. Ain't nobody got time (or wash) fo' that!
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Re: Speed of stripping & speed of spirit runs

Post by skow69 »

+1. More data better. Or you could try running slow, then fast, then slow again, and fast again. If you do, be sure to allow plenty of time for the still to react. And we'll have to remember to compensate for the natural changes in the distillate over the course of a run. I know that makes that test problematic, but I dont have a better one up my sleeve.

Fan away, Badmo, I'm still planning that consecutive double run, just life got in the way for a bit.
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Re: Speed of stripping & speed of spirit runs

Post by sungazer »

NZChris wrote:If you have the capability to shoot a jar back into the pot, you could run the same jar fast and slow with the same starting ABV in the pot. I don't, but it could be arranged.
Off topic but I do have this ability and use it sometimes if I miss the end cut off. I simply pour that last bottle or as you guys use the term jar back down the top of the condenser coil. I have to take a little cap off but that is pretty simple then as I know how much was too much I can watch a little more closely and slow her down before I get to the end.
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Re: Speed of stripping & speed of spirit runs

Post by rad14701 »

sungazer wrote:
NZChris wrote:If you have the capability to shoot a jar back into the pot, you could run the same jar fast and slow with the same starting ABV in the pot. I don't, but it could be arranged.
Off topic but I do have this ability and use it sometimes if I miss the end cut off. I simply pour that last bottle or as you guys use the term jar back down the top of the condenser coil. I have to take a little cap off but that is pretty simple then as I know how much was too much I can watch a little more closely and slow her down before I get to the end.
Be VERY careful pouring anything down a running reflux column as you could accidentally end up with a face full of steam or liquid spirits... Straight into the boiler would be safer... Or cut the heat...
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Re: Speed of stripping & speed of spirit runs

Post by ShineRunner »

So I did the stripping run yesterday. I know it's kind of already been done, but all I could really do was match the fast/slow stripping speeds. I did about 25 jars of 150 ml collection, dumping into the hydrometer jar and then dumping that into a collection jar. As I've said before, I only have a pwm controller, so set my dial at 1/4 and 1/2. The duty cycle wasn't really measurable, so I measured the collection rates. I took a 6 oz foreshot cut and then started collecting.

The low power collection was painfully slow, so I cut it off after 26 jars and cranked it up to collect quickly.

I can't figure out how to add a chart? I don't really want to host it anywhere.. The chart shows a fairly clear line with occasional bumps right near the power changes, but ultimately the line follows the same slope all the way through. Seems as though the changes were well within my error to read the hydrometer. It was coming out pretty fast on the higher power setting and was difficult to accurately read.

Subjectively, I'd say that the slow and low jars smelled a little cleaner, but was really difficult to differentiate. I would agree with the previous subjective reports (I think by badmo) that there were potentially a few more jars of hearts with the slower section.

Jar % Power % flow rate mL/min
1 25 122 38
2 25 120 38
3 25 116 38
4 25 114 38
5 25 112 62.5
6 50 112 90
7 50 110 90
8 50 107 90
9 50 104 90
10 50 102 90
11 50 99 90
12 50 96 90
13 25 96 28.6
14 25 95 28.6
15 25 95 28.6
16 25 94 28.6
17 50 93 90
18 50 89 90
19 50 88 90
20 50 87 90
21 50 86 90
22 25 82 31
23 25 80 29.7
24 25 78 28
25 25 75 28
26 25 74 28


I'm open to any questions or criticisms. I know it's not perfect, but I thought I'd try to contribute at least a little with what I have available.
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Re: Speed of stripping & speed of spirit runs

Post by sungazer »

rad14701 wrote:
sungazer wrote:
NZChris wrote:If you have the capability to shoot a jar back into the pot, you could run the same jar fast and slow with the same starting ABV in the pot. I don't, but it could be arranged.
Off topic but I do have this ability and use it sometimes if I miss the end cut off. I simply pour that last bottle or as you guys use the term jar back down the top of the condenser coil. I have to take a little cap off but that is pretty simple then as I know how much was too much I can watch a little more closely and slow her down before I get to the end.
Be VERY careful pouring anything down a running reflux column as you could accidentally end up with a face full of steam or liquid spirits... Straight into the boiler would be safer... Or cut the heat...
Thanks I can see your point. Luckily for me I think the design of my still has prevented me from experiencing any of those effects and nasty accidents. However I will still be more careful in the future. I can see in especially in some designs this could be very dangerous.

I did put it in one post recently but I do have an overly long condenser coil and as a high rate of cold water. (I know the disadvantages of this) this is also in a separate column. The top of the cooling condenser is cold. One of the advantages to the design is I really don't need any product cooling condenser. The product does come out reasonably warm but certainly not hot.

So when I read here my design is not recommended because of cost I sort of have a little chuckle as I have never needed or wanted to build an extra lieberg to simply cool the product a meter, meter and a half or two meters of small diameter copper tube gives adequate air cooling to the product.
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Re: Speed of stripping & speed of spirit runs

Post by skow69 »

I'm pretty shakey on your procedure. More details would help.
ShineRunner wrote:I can't figure out how to add a chart?

I turn them into jpgs or PDFs and use UPLOAD ATTACHMENT.

Subjectively, I'd say that the slow and low jars smelled a little cleaner, but was really difficult to differentiate. I would agree with the previous subjective reports (I think by badmo) that there were potentially a few more jars of hearts with the slower section.

We really need a way to quantify these things.

Jar % Power % flow rate mL/min
1 25 122 38
2 25 120 38
3 25 116 38
4 25 114 38
5 25 112 62.5
6 50 112 90
7 50 110 90
8 50 107 90
9 50 104 90
10 50 102 90
11 50 99 90
12 50 96 90
13 25 96 28.6
14 25 95 28.6
15 25 95 28.6
16 25 94 28.6
17 50 93 90
18 50 89 90
19 50 88 90
20 50 87 90
21 50 86 90
22 25 82 31
23 25 80 29.7
24 25 78 28
25 25 75 28
26 25 74 28

What is the third column, proof? I find it easier to work with %ABV. Simplifies the math sometimes. Each jar was 150 ml (5 oz.), right?

I'm open to any questions or criticisms. I know it's not perfect, but I thought I'd try to contribute at least a little with what I have available.

Thanks for your efforts. Can we see a picture of your rig? What heating element do you use?
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Re: Speed of stripping & speed of spirit runs

Post by der wo »

Is the head and the lid of the still insulated?
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Re: Speed of stripping & speed of spirit runs

Post by skow69 »

Here is ShineRunner's run.
abv x SPEED.png
abv x SPEED.png (10.29 KiB) Viewed 2721 times
Looks like a single curve to me.
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Re: Speed of stripping & speed of spirit runs

Post by der wo »

skow69 wrote:Looks like a single curve to me.
For me too. I am looking forward to the details of ShineRunners still.
Thank you ShineRunner, thank you skow.
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Re: Speed of stripping & speed of spirit runs

Post by ShineRunner »

Hey guys, looks like you figured out the 3rd column is proof, not %ABV. Each jar was 150 ml, which was tough to read on the fast run. I brought it up to temp with about 1/2 power to avoid puking. As soon as fores started running, I slowed it to 1/4 on the dial. Tossed 6 oz of fores then started collecting 150ml increments.

I'll have to get a picture of the setup next time, but it's a 15.5 gallon keg with a hole cut in the top. I use a camco ULWD 5500w element on 220. The PWM cycles on about 43 times per minute, but the length of "on" time varies based on the dial. Hard to measure the cycle, but I'd say at 1/4 power it was on a little less than a second and off a little more. The keg was insulated with a hot water heater insulation wrap pretty much all the way around. Just on the sides.

The "head" is just an upside down mixing bowl that is attached via flour paste and bolts that stick up through the top. Wing nuts with bent washers tighten it down. The lyne arm is 1/2" soft tubing that runs about 4 feet (uninsulated) over to a worm in a bucket.

Any other questions?
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Re: Speed of stripping & speed of spirit runs

Post by ShineRunner »

Thinking about the spirit run for this...

I could use my original 5 gallon pot to run 2 separate 4 gallon runs. One fast and one slow. It would have to be run on the stovetop, unfortunately. The pot is triple bottomed and is somewhat resistant to smearing (which I agree doesn't really happen with power cycling). The head and everything else would be the same as my keg. It would be a smaller scale run and wouldn't be as powerful as the internal element, but it would allow data collection nonetheless.

Not sure I have enough jars though. I think I have about 25 pint jars. Collecting 150ml at a time would go through those jars pretty fast.

As for making cuts, I was thinking about a blinding system of randomly generating letters to represent the jar number. I would label them on the day of the run and input it into the spreadsheet. After 2 days of airing out, I would have no memory of what letter corresponds to which jar number or run. Perhaps I could have my wife mix them up so I would be blind to which is which. It might be pretty tedious to completely randomize the jars, so maybe I could just have her keep the run together but mix up which run is fast vs slow. Just spitballing here. Any ideas?

As for having anyone else test for cuts, for repeatability, I don't have anyone who has any experience. I have a friend who is aware of my activities, who is a whiskey lover. I could possibly involve him, but not sure how reliable that would be since he's never made cuts before.

Open to suggestions...
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Re: Speed of stripping & speed of spirit runs

Post by skow69 »

I finally made my double run. I started with two 5 gallon carboys of sugarhead built on spent grains, or gumballhead, as Jimbo would say. The only ingredients were corn, barley, rye, sugar, yeast, water, and calcium carbonate. One estimated at 8.6% ABV, the other at 9.9%, by refractometer and calculated on this sitehttp://onebeer.net/refractometer.shtml. I racked 3 7/8 gallons off of each into a big cooler and stirred. For each run I measured 3 7/8 gallons into the boiler and charged the thumper with 1/2 gallon of feints at 28% ABV.

My potstill runs under vacuum in a water bath on an LP cooktop and with a 1000 watt band heater.
there is no insulation. For the slow condition I eliminated the band heater so the difference between conditions is an even 1000 watts, less whatever escapes to the environment. All jars are 12 oz. each. All alcoholometer readings were taken at 65F uncorrected.

The slow run averaged 16 minutes per 12 oz. jar, or .75 oz./minute = 45 oz./hour.
The fast run averaged 5.5 minutes per 12 oz. jar, or 2.2 oz./minute = 132 oz./hour.
The fast rate was 3X the slow rate.

Here is the data. T=time in minutes to fill the jar.
slow.jpg
fast.jpg
And the chart.
abv x SPEED.png
abv x SPEED.png (12.16 KiB) Viewed 2611 times
The slow run was generally higher ABV, as predicted by our hypothesis. The average difference between the curves is 3% for the area where they are parallel. Not much, but probably significant. As always, only more trials could tell.

The more interesting parts may be the ends of the curves. I usually strip into a single jug so I don't have any experience to fall back on here. I am surprised that it took 2 jars, 24 oz., for the ABV to max out on the fast run, when the slow run hit max right out of the gate. I'm used to the (spirit run) foreshots being a few ABV low, but the first jar difference here was 16%. The only difference between conditions that I can come up with is the heat.

If we apply the beginning observations here to the familiar Alcohol Curve chart, we find that the slow run should have started with a wash of around 27%, and the fast run around 12%. Of course that is not strictly accurate because of the effect of the thumper, but, again, the runs were identical to the best of my ability with the exception of the heat. I don't know what to do with that.

At the other end the curves crossed, exactly as predicted by Badmotivator if the hypothesis was correct. I didn't put much stock in the idea when he presented it, partially because I don't remember ever seeing that effect discussed before. So as far as I know Badmo thunk it up all on his own. The irony is killing me.

I think this has to be taken as evidence that running slow does result in higher ABV through the main body of the run, but the effect is very small. By implication I think that means that there is some hope that running slow could result in better separation of the fractions, but I wouldn't go to bat for it. It is now looking more like superstition than science. Overall, I have much less faith in the hypothesis now than I had at the beginning of this thread.

I hope we get more trials. I think we are at a point where more could be learned, but they won't be coming from me. I am just not curious enough to do any more 3 hour strips.
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Re: Speed of stripping & speed of spirit runs

Post by Badmotivator »

Outstanding! Thank you for taking the time to do this and share your results.
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Re: Speed of stripping & speed of spirit runs

Post by der wo »

Thank you.

I started today fermenting fertilized bw for two stripping runs. I will do a comparison insulated lid vs uninsulated lid, same wattage.
Each will be after clearing around 11l 12.5%abv. It will need time to ferment, because it's cold.
I think I will run the still with 2000W. Measuring abv with a thermometer at the highest vapor point. First measure after 20ml distillate (foreshots) and then every 200ml.
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Re: Speed of stripping & speed of spirit runs

Post by Badmotivator »

I also have another trial coming up. Three 8 gallon strips: 1) as fast as possible with minimal reflux, 2)very slow with maximal passive reflux, and 3) fast as possible with one one bubble cap plate.

The questions I hope to answer are: what is the maximal size of the passive reflux phenomenon for home distillers, and how does that compare to a minimal case for a reflux still? My hunch is that the first two will show a measurable but insignificant divergence, as we have seen in previous experiments, and that the third will show a significant jump.
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Re: Speed of stripping & speed of spirit runs

Post by raketemensch »

Huge thanks to all of you who are doing runs to provide data. If the low & slow myth is disproven, this would be a huge thread in HD history.
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Re: Speed of stripping & speed of spirit runs

Post by masonsjax »

How could passive reflux have any bearing? I'm seriously asking. I would assume that anything that condenses on the way up will just roll back down into the boiler. That's not reflux and should have zero impact on anything. Right?
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Speed of stripping & speed of spirit runs

Post by Badmotivator »

masonsjax wrote:How could passive reflux have any bearing?
It's a good question, masonsjax. Here's how it might happen: vapor goes high up the pipe and some condenses. On its way back down the walls of the pipe it is very hot (not boiling!) and so has a somewhat high vapor pressure, and the vapor coming off of the wall-running-liquid will be enriched in the more volatile components. This will have the effect of enriching the vapor stream.

By how much? Depends on geometry and probably power, but in any case it is probably a very very small effect, and probably vanishes in importance compared to a plate or packing with active reflux. But that's what we'd like to know! Power Myth defenders have cited passive reflux as an explanation and justification for slow spirit runs.
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Re: Speed of stripping & speed of spirit runs

Post by Jimbo »

Passive reflux.....what happens, just as in active reflux, the higher boiling point molecules (water) condense first onto that cooler copper tower wall. Leaving a greater proportion of lower boiling molecules (ethanol) remaining to travel into your product condensor. (Higher ABV) build a 6 foot tower or a big onion and youll have plenty of passive reflux and a higher ABV product than a 1' tower, all else being equal.
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Re: Speed of stripping & speed of spirit runs

Post by sungazer »

This is a real important fundamental for everyone to understand. It is part of the reading that most people talk about. But just to bring it to the for front rather than have to look it up.

The other important thing to learn from this that most people overlook or try to force and control is that the cooling up the tower will occur naturally. Condensing the vapor and returning it as liquid is not essential if you had a tall enough column and did not put too much power in. Returning a liquid back down the column is the next best way if you cant achieve the first way.

"Each of these "steps" represents an "ideal plate" where enough mingling of liquid & vapour allows them to come to equilibrium. If you don't allow enough mingling (equilibrium), then you won't achieve a full step, but end up a little shy of the target. You get the first step free - its the boiler/pot.
Basically, off a 10% wash
1 = 53%
2 = 80%
3 = 87%
4 = 90%
5 = 92%
6 = 92.6%
7 = 93.3%
8 = 93.8%
9 = 94.2%
10 = 94.4%

One way of doing these steps is to do many single distillations, collect the vapour that comes off, condense it, clean out the still, and run it through the still again. This why pot stillers do double & triple distillations to get into the 80+ % range. But a Reflux column allows this to happen continuously; if given enough surface area to equilibrate on, the vapour can have gone through multiple distillations by the time it gets to the top of the column.

For each plate to work, it has to be at a particular temperature, slightly cooler than the one below, and warmer than the one above. Only then will it achieve its equilibrium and an increase in the alcohol purity. The differences are really fine too — its all happening only between 78.1 C and 82.2 C — quite a tight band to walk between.

Mike Nixon explains in a bit more detail ...

The process of separation depends on two facts:

1) when a vapor condenses then the resulting liquid has the same composition as the vapor, and the temperature at which this occurs is the same as the boiling point of that mixture. The boiling point lowers as the proportion of volatiles increases, so the temperature as you go up a column naturally decreases. One sticking point is that many think that a vapor only condenses when it encounters a surface that is cooler than the boiling point, but this is not so. Condensation occurs when there is a path for the latent heat of vaporization/condensation to be removed from the vapor, and the resulting liquid will remain at its boiling point if no further heat is removed.

2) when this liquid re-evaporates then the resulting vapor is richer in the most volatile components.

The packing is there simply to hold intermediate distillate in place so it can be bathed in hot, rising vapor and allow this second process to occur. As volatiles are further extracted from the intermediate distillate, the boiling point of what remains increases and the depleted liquid builds up, eventually dripping down the packing to a hotter level where it can again be stripped of more volatiles.

A cooling tube placed near the bottom of a column simply interrupts this natural progression and serves no useful purpose in the separation process. In contrast, the top cooling tube IS useful as it helps to return some of the vapor arriving at the top of the column to the packing, where it has a further chance of being stripped more thoroughly. This is what a condenser placed on top of a compound column does, but with more efficiency."
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Re: Speed of stripping & speed of spirit runs

Post by HDNB »

Badmotivator wrote:
masonsjax wrote:How could passive reflux have any bearing?
It's a good question, masonsjax. Here's how it might happen: vapor goes high up the pipe and some condenses. On its way back down the walls of the pipe it is very hot (not boiling!) and so has a somewhat high vapor pressure, and the vapor coming off of the wall-running-liquid will be enriched in the more volatile components. This will have the effect of enriching the vapor stream.

By how much? Depends on geometry and probably power, but in any case it is probably a very very small effect, and probably vanishes in importance compared to a plate or packing with active reflux. But that's what we'd like to know! Power Myth defenders have cited passive reflux as an explanation and justification for slow spirit runs.
i would suggest the opposite occurs, with the same result. water would condense out of vapour onto cooler surfaces, leaving behind a more volitile vapour.

edit: posting with sungazers much more eloquent response ^^^
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Badmotivator
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Re: Speed of stripping & speed of spirit runs

Post by Badmotivator »

Cool. To be honest, I'm personally not all that interested in whether the passive reflux represents differential condensation (HDNB) or differential re-vaporization (sungazer). I mean no disrespect to those who are, or those who want to talk about the concept, it's just not my jam.

What does interest me is whether passive reflux can can justify a slow spirit run, given a typical small pot still. Many have asserted that it can, though without detailing the quality of their information. I'm going to test it as carefully as I know how. Maybe the conventional wisdom is correct? Yay! Better spirits! Maybe the CW is wrong. Yay! Faster spirit runs for the same product!
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Re: Speed of stripping & speed of spirit runs

Post by snowman_fs »

Overall I think this is a great thread that I would like to contribute data from my next runs to. Until then I will submit that my observations from runs show that when power is increased from my classic "hearts" power to my "speed up and finish" power that the abv collection continues to decline, (without any discontinuities) as shown by Badmotivator and others here. My still specs: 50L keg, 5500W w/ 2s PWM period, no insulation. I run 35L strips (with feints added) at about 10% abv. I have only bumped the power by +25% so the input variable change is minor compared to the 3x shown here but I'm willing to try a 2 kW and 5.5 kW next time in the hopes I could confirm my growing suspicion that I can run faster. Maybe after the fores are collected slowly; leveraging the extra reflux induced by still warmup and then just transitioning to full speed will be my new normal.
cranky wrote: The vapor rising through the liquid was actually swirling in a slow (ish) (I think) clockwise direction viewed from the top. I assumed this was caused by the shape of the keg but I can also see that the element location could contribute to this.
This statement caught my eye having experience in industrial pumping. We see the Coriolis effect in vertical flow even where speeds are low enough to be considered laminar. The rotation from Coriolis becomes even more visible when a pipe discharges; It always comes out with a rotation bias. Just sayn'.

I would like to also propose a test configuration where a CCVM still head is used on the pot with no packing. It would have the ability to run at constant power and allow the reflux ratio to both be measured and adjusted. Would this not simulate and exaggerate the extra passive reflux from running slow?
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Re: Speed of stripping & speed of spirit runs

Post by googe »

If im following this right, your all trying to say running slow with high abv wash with a pot will get good product, and fast with low abv will result in similar?. Running slow for heads, faster for hearts?. 4" will get slot of passive reflux, my Plater would run 65~72% at 13lph stripping, plates would be around half loaded with no reflux coolant. You need something in the path to interfere with the rising vapor to bump abv, plates, packing. I thought it was a known fact that more vapor= more passive action= higher abv no.matter still type.
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