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blogfast25
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Quote: Originally posted by Etaoin Shrdlu  | If you only test one method, you can only say that that one method doesn't work, aside from some reasonable extrapolations. And there are so many
methods there could be people out there with excellently working thumpers, and a bunch of others not getting any improvement but suffering from some
quasi-placebo effect, they could all work to some extent, they could all be bunk...
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You are making this more complicated than it is, IMO. This is a fairly simple thing to do. While universalism can strictly speaking not be claimed, if
a simple set up shows results either way it's very reasonable to assume the conclusion will be more or less universal.
With your approach I would need to test every single apple, to make sure they all fall to earth.
I also suggest you look at various sources and youtubes under 'moonshine thumper' and similar search terms. Have a good laugh...
Try and find one decent, even semi-academic, source on it. You won't find it.
[Edited on 17-2-2015 by blogfast25]
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Loptr
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| Quote: Originally posted by blogfast25 | | Quote: Originally posted by Luke | | How are you going to decide how much energy to put into the setup with a thumper and the setup without a thumper? The setup with a thumper is going
to need more energy. |
The thumper people don't do that either: they just heat.
We will heat both the same way, that's a fair comparison.
You are of course already trying to pick holes and we haven't even done anything yet!
I suggest that as a 'believer' you run your own experiment, one in which you account for all heats. |
I lol'd when I read "thumper people". 
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blogfast25
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Loptr:
Whatever makes you happy.
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blogfast25
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| Quote: Originally posted by Zombie | Ok,
I have a stick rendering, and I think all the important guidelines.
Just a few common sense ones here... Pot / thumper as close together as possible.
Both at same level (bases)
Flow rate of output is critical. Minimum product condensing water flow, and minimum heat required to maintain a broken stream into collection vessel.
This is the MOST IMPORTANT point I can make...
The outcome has no teams or bragging rights.
I have too much respect for all of you that are involved to make this a pissing contest.
Any questions along the way I will be happy to provide input, without changing parameters or running for the other goal.
This is the first time that I can find that anyone has run this experiment. That does not mean it has not been run before but from where I sit, the
results have a real world value.
Thank you all for this marathon 22 hour keyboard session. God Bless...
Ken
Had to edit: control heat to maintain a broken stream condenser out put
(that got lost from the image)
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There's much to pick on there but it will have to wait till tomorrow night. You do make laugh, I'll grant you that...
Night night.
[Edited on 17-2-2015 by blogfast25]
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Zombie
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| Quote: Originally posted by Luke | | How are you going to decide how much energy to put into the setup with a thumper and the setup without a thumper? The setup with a thumper is going
to need more energy. |
This is stated in the parameters.
The out put stream is the throttle. You monitor this stream for a steady broken stream into the collection vessel.
I assume one "control run will be needed to set the product condenser to knock down vapor, and get a feel for the heat needed.
Slow even heat will not de rail the results, as long as the out put rate is slow, and controlled thru the run.
you do have to watch, as the changing ABV / BP directly translates to output.
In BOTH tests the stream will runs faster, and the Alch depletes. so even if there is operator error it will balance, and yield the same results in
both tests.
No worries.
They tried to have me "put to sleep" so I came back to return the favor.
Zom.
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Zombie
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| Quote: Originally posted by blogfast25 | | Quote: Originally posted by Zombie | Ok,
I have a stick rendering, and I think all the important guidelines.
Just a few common sense ones here... Pot / thumper as close together as possible.
Both at same level (bases)
Flow rate of output is critical. Minimum product condensing water flow, and minimum heat required to maintain a broken stream into collection vessel.
This is the MOST IMPORTANT point I can make...
The outcome has no teams or bragging rights.
I have too much respect for all of you that are involved to make this a pissing contest.
Any questions along the way I will be happy to provide input, without changing parameters or running for the other goal.
This is the first time that I can find that anyone has run this experiment. That does not mean it has not been run before but from where I sit, the
results have a real world value.
Thank you all for this marathon 22 hour keyboard session. God Bless...
Ken
Had to edit: control heat to maintain a broken stream condenser out put
(that got lost from the image)
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There's much to pick on there but it will have to wait till tomorrow night. You do make laugh, I'll grant you that...
Night night.
[Edited on 17-2-2015 by blogfast25] |
Thanks... I needed that. You really know how to pick a topic!
They tried to have me "put to sleep" so I came back to return the favor.
Zom.
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Etaoin Shrdlu
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| Quote: Originally posted by blogfast25 | | Quote: Originally posted by Etaoin Shrdlu | If you only test one method, you can only say that that one method doesn't work, aside from some reasonable extrapolations. And there are so many
methods there could be people out there with excellently working thumpers, and a bunch of others not getting any improvement but suffering from some
quasi-placebo effect, they could all work to some extent, they could all be bunk...
|
You are making this more complicated than it is, IMO. This is a fairly simple thing to do. While universalism can strictly speaking not be claimed, if
a simple set up shows results either way it's very reasonable to assume the conclusion will be more or less universal.
With your approach I would need to test every single apple, to make sure they all fall to earth. |
No, of course not. Generalizing to all apples for the most part would be fair enough. But, say, generalizing to apples in orbit, or on other planets,
or dropped over a trampoline, would probably be a mistake.
Like I said, I'd accept the result of whatever your experiment is as probably indicative of the efficacy of thumpers in general. But I'd still keep my
mind open to the possibility that someone might show up with a tweak to the parameters that really did work.
| Quote: Originally posted by blogfast25 | I also suggest you look at various sources and youtubes under 'moonshine thumper' and similar search terms. Have a good laugh...
Try and find one decent, even semi-academic, source on it. You won't find it. |
I tried. There are none I could find. And you're right, it was mostly quite funny.
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macckone
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A thumper is just like a plate in a commercial distillation tower.
Assuming the thumper is filled with alcohol that is richer than
The pot still the distillate will be richer in alcohol up to the azeotrope.
Yes the thumper absorbs heat and requires more to complete the
Distillation but it is hypothetically less heat than two distillations.
I run a reflux still for water and it uses a lot more heat but also
Provides the equivalent of triple distillation in one pass.
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Fulmen
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No. It is not a full plate step since no liquid is returned. That makes it a fractionate condenser. The problem is that according to Zombie it is
filled with fresh mash (say initially 10%) and ends up the same strength as the spent mash (2-3%). This doesn't add up.
We're not banging rocks together here. We know how to put a man back together.
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Chemosynthesis
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Let's assume the thumper works, and does work as either a second distillation stage, or a plate, or however one wants to view it.
Does anyone have opinions on the ethanol holdup? I'm looking at DeltaH in particular. Obviously, the traditional method of increasing theoretical
plates is to increase surface area, and this results in more holdup, proportional to this increase. With a thumper, you have a multi-phase system that
now takes into account Raoult's law [edit- from the first stage. Duh, Raoult's law applies in distillation. Additional terms]. If, and I am still
using a hypothetical here, a thumper can be substantiated as a valid design with some empirical, quantified data... I would be very curious to see how
efficient one would be relative the surface area or length of a column, and then try to determine if one is better or worse than the other in terms of
mechanical yield loss due to holdup.
[Edited on 17-2-2015 by Chemosynthesis]
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Luke
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Ok cool, so you are going to be running the still as it would traditionally be run.
I dont know whether one system would require more power over the other but it should be a consideration. But if you are going to be doing it by
output flow rates there won't be a problem.
| Quote: Originally posted by Zombie | | Quote: Originally posted by Luke | | How are you going to decide how much energy to put into the setup with a thumper and the setup without a thumper? The setup with a thumper is going
to need more energy. |
This is stated in the parameters.
The out put stream is the throttle. You monitor this stream for a steady broken stream into the collection vessel.
I assume one "control run will be needed to set the product condenser to knock down vapor, and get a feel for the heat needed.
Slow even heat will not de rail the results, as long as the out put rate is slow, and controlled thru the run.
you do have to watch, as the changing ABV / BP directly translates to output.
In BOTH tests the stream will runs faster, and the Alch depletes. so even if there is operator error it will balance, and yield the same results in
both tests.
No worries. |
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deltaH
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| Quote: Originally posted by Chemosynthesis | Let's assume the thumper works, and does work as either a second distillation stage, or a plate, or however one wants to view it.
Does anyone have opinions on the ethanol holdup? I'm looking at DeltaH in particular. Obviously, the traditional method of increasing theoretical
plates is to increase surface area, and this results in more holdup, proportional to this increase. With a thumper, you have a multi-phase system that
now takes into account Raoult's law [edit- from the first stage. Duh, Raoult's law applies in distillation. Additional terms]. If, and I am still
using a hypothetical here, a thumper can be substantiated as a valid design with some empirical, quantified data... I would be very curious to see how
efficient one would be relative the surface area or length of a column, and then try to determine if one is better or worse than the other in terms of
mechanical yield loss due to holdup.
[Edited on 17-2-2015 by Chemosynthesis] |
Not so sure what you mean by the ethanol holdup here, can you clarify, please?
***
As for the liquid in the thumper, as a poor second stage, it's alcohol content is probably higher than the still and lower than the final distillate
at all times. So towards the end of the run, when the conc. of the alcohol in the still is much lower, then so too would the conc. of the alcohol in
the thumper be, but still higher than the still's. Anyway, the conc. of alcohol recovered in batch distillate starts out high and ends low as well.
It's for the distiller to decide when to stop pulling and so this sets the overall recovery. He decides when to stop because the conc. drops too low
towards the end. The thumper ups conc. by acting as a partial second plate, so that allows the distiller to continue the run a little longer before
reaching the same low conc. of distillate he would have for a single stage... so I would imagine it improves overall recovery in a batch operation,
but that's speculative. Again, it would have been nice to model all this, but none of the free software I have can do non-steady state calculations
for batch distillation.
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DJF90
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| Quote: Originally posted by blogfast25 | | Quote: Originally posted by DJF90 | It wouldn't be the first time you've been wrong, would it Gert? The reduction of potassium hydroxide by magnesium (stickied thread) rings a distict
sounding bell.
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Great logic, DJF90. I was wrong about something ergo I must be wrong about this too. Even basic logic escapes you. Smearing on the other hand
suits you down to the ground. |
I never said you was wrong about this, just that its not incomprehensible that you could be. No need to be a cunt about it, eh?
Members tried replicating a patent/Pok's work and had difficulties getting the same result, mostly because they failed to actually replicate the work
that had been done. It didn't help that it is a finicky reaction, but incompetence doesn't help either.
| Quote: Originally posted by blogfast25 |
Re. experiments on thumpers, a fellow experimenter and myself will carry out this experiment. Unlike you of course...
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Like many others here I don't have the free time to do experimental work at home anymore. You're the one starting the thread, you're the one wanting
answers - you do the work. I think that asking Zombie for his experience and then dismissing his claims without any real-world experience of your own
was rude and inappropriate. I'm surprised he's still willing to assist you; personally I'd have told you to piss off.
I don't know if the thumper works as advertised or not, but I didn't claim to either. However, I think it is not an unreasonable claim to make. These
guys aren't after excellent efficiency, otherwise they would be using proper fractionating columns; they just want a little bit more from their
distillation, and if the thumper provides that then fair play to them.
[Edited on 17-2-2015 by DJF90]
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blogfast25
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| Quote: Originally posted by DJF90 | | I never said you was [sic] wrong about this, just that its not incomprehensible that you could be. No need to be a cunt about it, eh?
|
It's NEVER inconceivable that I'm wrong. It simply goes w/o saying.
| Quote: Originally posted by DJF90 | | Members tried replicating a patent/Pok's work and had difficulties getting the same result, mostly because they failed to actually replicate the work
that had been done. It didn't help that it is a finicky reaction, but incompetence doesn't help either. |
INCOMPETENCE????? Like Len1, woelen and many others I was initially sceptical of the claim until I had my own first successful run. I became the main
experimenter and caretaker of the thread and another related one. What have you done? Ah, wait, behave like a CUNT, that you HAVE done. And
it's not the first time either!
As regards the point that it's me that has to do the work? On what grounds? Zomb is making very strong claims, so why is he absolved? Because a twit
like you says so? Pffffff....
GO AWAY, you old gossip queen! 
[Edited on 17-2-2015 by blogfast25]
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blogfast25
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I'll be back later to discuss operating conditions with Zomb, I have work to do right now.
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Fulmen
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| Quote: Originally posted by deltaH |
As for the liquid in the thumper, as a poor second stage, it's alcohol content is probably higher than the still and lower than the final distillate
at all times. |
Exactly. If you look at the sim i uploaded you can clearly see this. You're basically splitting the output from the boiler into two streams, and if
you look at the mass/molar balances you'll see that the total output must be the same.
As long as nothing is returned to the boiler the output must be the same, right? And some of the product must condense in the thumper for it to have
any effect, right? After all the output from the boiler is saturated vapor, so any heating must come from condensing some of the vapor.
We also know that there is an equilibrium between vapor and liquid, you can never condense pure water from water/alcohol vapor. So some alcohol MUST
condense out in the thumper.
If you combine the content of the thumper and the remainder from the boiler you should see that the concentration will be higher than without a
thumper, basically you're stopping the still earlier.
We're not banging rocks together here. We know how to put a man back together.
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blogfast25
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Light relief:
My favourite still/thumper design:
http://stillplans.net/moonshine%20still%20single.htm
Enjoy! Order! Haggle! Now with NEW 'Tilt Reflux Technology'!
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Chemosynthesis
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| Quote: Originally posted by deltaH |
Not so sure what you mean by the ethanol holdup here, can you clarify, please?
***
As for the liquid in the thumper, as a poor second stage, it's alcohol content is probably higher than the still and lower than the final distillate
at all times. So towards the end of the run, when the conc. of the alcohol in the still is much lower, then so too would the conc. of the alcohol in
the thumper be, but still higher than the still's. Anyway, the conc. of alcohol recovered in batch distillate starts out high and ends low as well.
It's for the distiller to decide when to stop pulling and so this sets the overall recovery. He decides when to stop because the conc. drops too low
towards the end. The thumper ups conc. by acting as a partial second plate, so that allows the distiller to continue the run a little longer before
reaching the same low conc. of distillate he would have for a single stage... so I would imagine it improves overall recovery in a batch operation,
but that's speculative. Again, it would have been nice to model all this, but none of the free software I have can do non-steady state calculations
for batch distillation.
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This does a better job explaining it than I can. The holdup often leads to mechanical losses due to surface area, especially in packed columns, unless
you feel like washing out all your contact surfaces.
Attachment: liquidholdup.pdf (194kB)
This file has been downloaded 2382 times
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DJF90
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| Quote: Originally posted by blogfast25 |
| Quote: Originally posted by DJF90 | | Members tried replicating a patent/Pok's work and had difficulties getting the same result, mostly because they failed to actually replicate the work
that had been done. It didn't help that it is a finicky reaction, but incompetence doesn't help either. |
INCOMPETENCE????? Like Len1, woelen and many others I was initially sceptical of the claim until I had my own first successful run.
|
Yes incompetence. It may pain you to hear it but if you try replicating someone elses work using different solvents/additives, you shouldn't be
suprised when it doesn't work. The experiment should have been performed exactly as Pok had reported, before modifications were made. Several pages of
poor results could have been avoided in such a manner.
I bet that made you feel real important. Good for you!
I try to provide constructive criticism; I can't help it if I come across as a cunt sometimes.
| Quote: Originally posted by blogfast25 |
As regards the point that it's me that has to do the work? On what grounds? Zomb is making very strong claims, so why is he absolved? Because a twit
like you says so? Pffffff....
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You started the thread, askig the question about thumpers. You solicited Zombies participation; its not up to him to have to prove anything to you. If
you want to show that thumpers work/don't work, then go do it.
Gossip queen? Kind of ironic that its you that double/triple/quadruple posts, isn't it. I bet anyone here could tell you who has the highest post
count on the board... its a shame the signal to noise ratio is so bad.
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blogfast25
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| Quote: | | Pot / thumper as close together as possible. |
We may not be able to do that but we will insulate the vapour line from still to thumper.
| Quote: | | Both at same level (bases) |
We can do that but why? What does gravity have to do with anything?
| Quote: | | Flow rate of output is critical. Minimum product condensing water flow, and minimum heat required to maintain a broken stream into collection vessel.
|
Slow distillation we can do. What does minimum condensing water flow have to do with anything? We don't want to LOSE any EtOH.
| Quote: | The outcome has no teams or bragging rights.
I have too much respect for all of you that are involved to make this a pissing contest. |
Pfff...
Question. Say 100 volume parts of 10 ABV feedstock. How much in the still, how much in the thumper at start of run?
Are we allowed to heat up thumper liquid at start, just to save a little time? Thumper heating will be switched off once it starts simmering. Heating
by still pot vapours then takes over.
I also note that many of these demand are COMPLETELY ignored by all thumper people on the tinkerwebs but anyway.
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blogfast25
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DJF, you boring old fart, go hang out at some chat room or other.
| Quote: Originally posted by DJF90 |
Yes incompetence. It may pain you to hear it but if you try replicating someone elses work using different solvents/additives, you shouldn't be
suprised when it doesn't work. The experiment should have been performed exactly as Pok had reported, before modifications were made. Several pages of
poor results could have been avoided in such a manner.
|
That point shows how LITTLE you know. The experiment has shown itself far less sensitive to materials than you think. All kinds of solvents, an
alternative catalyst, various physical forms of Mg... all work.
You're an idiot with an agenda. An incompetent gossip queen.
[Edited on 17-2-2015 by blogfast25]
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macckone
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One important fact that is missed a lot here is that the vapor stream has a
higher heat content than the azeotrope. This isn't some miracle violation
of the laws of thermodynamics. A thumper is going to be less efficient than
a true plate but more efficient than a second distillation based on heat input.
Once the thumper reaches steady state it loses its effectiveness.
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blogfast25
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Favourite Thumper Resources (Cough!):
http://homedistiller.org/equip/designs/thumper
You've gotta love this bit:
| Quote: | Jim writes ...
Run your doubling keg in a water bath makes a good drink and it's pure. Do not add no liquid it makes it's own liquid |
Video: don't strain your neck!
https://www.youtube.com/watch?v=sM1pGpU56HU
Microstill with 'doubler', unfortunately it was undrinkable. Oh well...
https://www.youtube.com/watch?v=D_Nye_fGe50
Pulling out all the stops: Vacuum and THREE thumpers!
https://www.youtube.com/watch?v=Vio9M0gkT5w
And all I asked for was a measurement or two...
[Edited on 17-2-2015 by blogfast25]
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macckone
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To answer a couple of blogfast's questions. The usual ratio is 1:3 from the original link. Assuming
that the starting and final abv are the same for the pot and thumper that would give 33% enrichment.
note that is simple mass transfer and doesn't account for heat transfer. Starting off with a cold
thumper seems to make more sense thermodynamically. Initially the stream will condense in the
thumper producing a higher abv in the thumper. Then the stream will start to pass through with the
water condensing out and alcohol being absorbed into the vapor stream. Once it reaches steady
state, the amount of water condensed must equal the amount of alcohol evaporated at a heat value
level. Note this is lower than when the thumper is absorbing heat. If the thumper is losing heat
to the environment the enrichment could be greater but never more than the mass value. Hypothetically
the thumper could be alcohol depleted at the end of the run yielding a higher gain than 33%.
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deltaH
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| Quote: Originally posted by Chemosynthesis | | Quote: Originally posted by deltaH |
Not so sure what you mean by the ethanol holdup here, can you clarify, please?
***
As for the liquid in the thumper, as a poor second stage, it's alcohol content is probably higher than the still and lower than the final distillate
at all times. So towards the end of the run, when the conc. of the alcohol in the still is much lower, then so too would the conc. of the alcohol in
the thumper be, but still higher than the still's. Anyway, the conc. of alcohol recovered in batch distillate starts out high and ends low as well.
It's for the distiller to decide when to stop pulling and so this sets the overall recovery. He decides when to stop because the conc. drops too low
towards the end. The thumper ups conc. by acting as a partial second plate, so that allows the distiller to continue the run a little longer before
reaching the same low conc. of distillate he would have for a single stage... so I would imagine it improves overall recovery in a batch operation,
but that's speculative. Again, it would have been nice to model all this, but none of the free software I have can do non-steady state calculations
for batch distillation.
|
This does a better job explaining it than I can. The holdup often leads to mechanical losses due to surface area, especially in packed columns, unless
you feel like washing out all your contact surfaces. |
Read your attachment, yes the holdup you mentioned is the same holdup I was taught in column design... way-back, glad the term is international
I will add this extra blah blah:
as you know, the ethanol-water equilibrium is very non-ideal and disobeys the classical Raoult's law and this causes the equilibrium curve on it's x-y
diagram to bulge strongly at low concentration, here I've drawn it for water ethanol using the NRTL activity coefficient model and constants for this
system:
So the thermodynamic minimum number of ideal stages required to reach a certain concentration can be determined by drawing steps on this diagram
starting from your feed conc. This graph's axis in in mole fraction BTW.
The point is that starting somewhere close to the left-hand-side feed, two or three stages quickly moves you to pretty high alcohol concentrations,
thereafter it starts to get pretty damn hard to enrich further because the curve pinches the steps as you get close to the azeotrope.
What's the point? The point is because of that big bulge, you only need a couple of ideal stages to go a long ways, after that it, gets wasteful as
you need many stages to go slightly, this is because of the non-ideal behaviour of this system and the early bulge in that curve.
So really you don't need packing per say, two or three stages should work pretty nicely, provided they are well designed and you can operate close to
thermodynamically ideal stage. Packed columns are always an option though, but with all the hassle of finicky operation and problems like avoiding
flooding, etc. For continuously run columns, this is less of a control problem, but batch operations are tough because things change continuously by
definition.
That's why I've said before, I think it may be important to really take care to build the thumper well, as in try to maximise the size of the bubble
surface area that is formed below the liquid... within reason. Many small side holes are better than one big central one in the dip tube.
I watched a youtube video about large moonshine stills and I noticed that they emplyed V-shaped notches on the side of the thumper's tube, i thought
this was really clever, shows some decent understanding of mass transfer and the easy way to improve things.
Industrial bubble cup trays have caps with side holes too, so again, impressed by 'muntan 'schoolin 
EDIT: drew in a couple of stages' steps for those who don't know what I meant by it.
PS:
Notice how the second stage's step is so much larger that the first stage (boiler). It worthwhile to employ a second stage!
Again, these are thermodynamically ideal stages and you won't get near these in real stages, these step only partially towards the equilibrium curve.
[Edited on 17-2-2015 by deltaH]
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