Sciencemadness Discussion Board - Moonshiners' 'Thumpers': Myth or Reality?

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.

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]

Loptr - 16-2-2015 at 18:45

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".

blogfast25 - 16-2-2015 at 18:49

Loptr:

Whatever makes you happy.

blogfast25 - 16-2-2015 at 18:52

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)

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]

Zombie - 16-2-2015 at 19:00

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.

Zombie - 16-2-2015 at 19:04

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!

Etaoin Shrdlu - 16-2-2015 at 20:07

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.

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.

macckone - 17-2-2015 at 00:36

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.

Fulmen - 17-2-2015 at 00:52

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.

Chemosynthesis - 17-2-2015 at 00:53

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]

Luke - 17-2-2015 at 01:27

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 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.

deltaH - 17-2-2015 at 04:59

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.

DJF90 - 17-2-2015 at 05:04

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.

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?

What, by the way was wrong with the reduction of potassium hydroxide by magnesium. Do explain, you know?

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.

Re. experiments on thumpers, a fellow experimenter and myself will carry out this experiment. Unlike you of course...

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]

blogfast25 - 17-2-2015 at 06:06

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.

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! :mad:

[Edited on 17-2-2015 by blogfast25]

blogfast25 - 17-2-2015 at 06:08

I'll be back later to discuss operating conditions with Zomb, I have work to do right now.

Fulmen - 17-2-2015 at 06:27

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.

blogfast25 - 17-2-2015 at 06:49

Light relief:

My favourite still/thumper design:

http://stillplans.net/moonshine%20still%20single.htm

Enjoy! Order! Haggle! Now with NEW 'Tilt Reflux Technology'!

Chemosynthesis - 17-2-2015 at 06:59

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 2380 times

DJF90 - 17-2-2015 at 07:19

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 became the main experimenter and caretaker of the thread and another related one.

I bet that made you feel real important. Good for you!

What have you done? Ah, wait, behave like a CUNT, that you HAVE done. And it's not the first time either!

I try to provide constructive criticism; I can't help it if I come across as a cunt sometimes.

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....

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.

GO AWAY, you old gossip queen! :mad:

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.

blogfast25 - 17-2-2015 at 08:04

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.

blogfast25 - 17-2-2015 at 08:05

DJF, you boring old fart, go hang out at some chat room or other.

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]

macckone - 17-2-2015 at 08:17

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.

blogfast25 - 17-2-2015 at 08:31

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]

macckone - 17-2-2015 at 08:52

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%.

deltaH - 17-2-2015 at 08:52

Quote: Originally posted by Chemosynthesis

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:

x-y diagram for water ethanol with steps.jpg - 35kB

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]

DJF90 - 17-2-2015 at 08:56

I never disputed that. My point was that if someone had grabbed the right reagents and followed the prep as described, then it ought to have worked first time, and it would have saved a lot of aggrevation/disappointment. Perhaps you should try listening to what is actually said and not your narrow-minded mis-interpretation.

You're an idiot with an agenda. An incompetent gossip queen.

Don't you have an experiment to set up?

blogfast25 - 17-2-2015 at 09:12

1. Assuming
that the starting and final abv are the same for the pot and thumper that would give 33% enrichment.

2. Then the stream will start to pass through with the
water condensing out and alcohol being absorbed into the vapor stream.

Point 1: care to explain that?

Point 2: that is part of the thumper fallacy, of course; the idea that the water condenses out. It remains a two-component/two-phase system, as shown again by delta H.

blogfast25 - 17-2-2015 at 09:16

Don't you have an experiment to set up?

Complaining about timing already? Bit early methinks. The hard work will be carried out by a fellow SMer, as I'm quite badly ill right now. 2 - 3 weeks till results, I think.

Consider yourself ignored now, little troll.

I'll address you if you write something relevant to thumpers.

[Edited on 17-2-2015 by blogfast25]

blogfast25 - 17-2-2015 at 09:21

No contest there (but it's basic stuff).

We (Aga/me) found accordingly when comparing EtOH water distillation with and without a Vigreux column.

It explains why relatively simple stills can reach high 'proofs'.

deltaH - 17-2-2015 at 09:31

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%.

My simulations showed that a cold thumper does no enriching, enrichment only starts from about 73C under my conditions where it peaks rapidly, then decreases with increasing temperature. In really, the thumper would operate somewhere above 90C I would imagine and reach that pretty quickly. I would't proof a distillate sample before the thumper gets hot and reaches pseudo steady state.

[Edited on 17-2-2015 by deltaH]

deltaH - 17-2-2015 at 09:36

Exactly, just demonstrating the why to those who want to know.

blogfast25 - 17-2-2015 at 09:41

People should consider the following thought experiment.

A thumper is full of almost pure EtOH and at equilibrium temperature. The vapour coming off the still is almost 100 % water, at about 100 C and is led through the thumper.

What will happen? What will be the mole fraction EtOH coming off the the thumper (vapour) be?

deltaH - 17-2-2015 at 10:00

Nearly pure ethanol comes off if well mixed. As to the how, if you zoomed in on a single bubble of water vapour, water diffuses from the bubble into the alcohol and alcohol diffuses from the liquid into the bubble. When the water vapour enters the liquid at the edge of the bubble, it releases it's enthalpy of vaporisation and this is in turn absorbed by the evaporating ethanol. This continuous until equilibrium is reached (but never quite gets there). But that's not to say that ethanol vapour doesn't also diffuse back into the liquid as well, it is a dynamic system and molecules are constantly zooting too and fro, all the time, the rate of ethanol evaporating is simply large than it condensing and vice versa for water.

[Edited on 17-2-2015 by deltaH]

Magpie - 17-2-2015 at 10:02

The heat is supplied by the condensing of the incoming vapor from the still (latent heat). Efficient condensing would be promoted by having a high depth of submergence of the still vapor outlet pipe.

Enrichment of the thumper outlet vapor is based on the vapor-liquid equilibrium (VLE) curve for the system ethanol-water. Enrichment is due to the high relative volatility of alcohol to water in the region of interest, ie, around 20wt% alcohol of the liquid in the thumper. See Zombie's and deltaH's VLE curves.

This has been stated above several times. I'm just trying to say it more succinctly.

In regard to calling people genitals, Conan O'Brien said "what kind of a dick would call a person a vagina?"

[Edited on 17-2-2015 by Magpie]

blogfast25 - 17-2-2015 at 10:21

The heat of mixing of ethanol and water is exothermic by - 777 J/mol (Wiki), and all mixing is exoentropic.

So both ΔH and ΔG of mixing are negative (< 0).

To separate, that energy must be expended.

The idea that steam coming off the still provides that energy is fallacious. You need to look at the entire system: unheated thumpers simply introduce more heat losses. Insulated ones act like steam pipes.

And heated ones are a little more complicated than one might think. Primary still vapour would have to condensed to just below its BP. Once the thumper is, say, half full, a secondary distillation would be carried out by heating to BP and condensing the thumper vapours. But that wouldn't be a real thumper...

Fulmen - 17-2-2015 at 10:21

Magpie:
yes, the heat is supplied by the condensing of the incoming vapor. But what condenses? Lets start with .1 mole fraction vapor entering an empty, warm thumper. What will actually condense? Assuming that only a small fraction of the vapor condenses and full equilibrium between the phases?

blogfast25 - 17-2-2015 at 10:23

Nearly pure ethanol comes off if well mixed.

My point precisely: EtOH content coming off is lower than it was initially. Gradually EtOH content in thumper and its vapours decrease.

blogfast25 - 17-2-2015 at 10:28

The heat is supplied by the condensing of the incoming vapor from the still (latent heat). Efficient condensing would be promoted by having a high depth of submergence of the still vapor outlet pipe.

You're creating energy ex nihilo, Magpie. That energy you mention has already been accounted for. Latent heat has to be expended too, to revolatise the condensate.

[Edited on 17-2-2015 by blogfast25]

blogfast25 - 17-2-2015 at 10:35

Quote: Originally posted by Fulmen

Assuming that only a small fraction of the vapor condenses and full equilibrium between the phases?

Assume ALL of it condenses. That condensate's been enriched in EtOH of course, no contest whatsoever.

The fallacy is to consider the primary vapour led into the thumper liquid is just a heat source: it's not, it contains WATER!

The mole fraction EtOH coming off the primary still is of course already lower than that of any condensate formed in the unheated thumper.

deltaH - 17-2-2015 at 10:36

To separate, that energy must be expended.

I don't understand what you mean by this exactly. In a multi-trayed distillation column, heat is only inputted at the boiler and taken out in the condenser (usually), but every tray in the column is enriching more and more. Every tray is not individually heated though. So how does that work then?

Etaoin Shrdlu - 17-2-2015 at 10:47

Light relief:

My favourite still/thumper design:

http://stillplans.net/moonshine%20still%20single.htm

Enjoy! Order! Haggle! Now with NEW 'Tilt Reflux Technology'!

Oh god I'm dying of laughter.

deltaH - 17-2-2015 at 11:17

Just saw near the bottom that they offer a two thumpers in series version, was wondering about that. I guess the enrichment effect of a second thumper is probably much smaller than the first?

blogfast25 - 17-2-2015 at 11:23

Every tray is not individually heated though. So how does that work then?

It doesn't have to be. Heat is provided by the boiler. The column itself, in a ideal scenario, operates adiabatically (ΔH = 0). Things constantly condense and re-volatise. At the end you get your energy back in the condenser(s), MINUS what was expended for the separation.

My point with regards of Magpie's Latent Heat is precisely that: condensation occurs and latent heat is released but evaporation also occurs and consumes latent heat.

[Edited on 17-2-2015 by blogfast25]

Loptr - 17-2-2015 at 11:27

Light relief:

My favourite still/thumper design:

http://stillplans.net/moonshine%20still%20single.htm

Enjoy! Order! Haggle! Now with NEW 'Tilt Reflux Technology'!

Oh god I'm dying of laughter.

They also spell it "Wight Lighting".

[Edited on 17-2-2015 by Loptr]

blogfast25 - 17-2-2015 at 11:28

Oh god I'm dying of laughter.

What's also funny is that his refluxer certainly works (despite the pompous name) but does anyone believe his little pickle jar would work? It's certainly hopelessly under-dimensioned, looking at the size of the pot. That thing would fill up in no time!

Molecular Manipulations - 17-2-2015 at 11:35

Try Gallagher's "Milk of the Gods"

blogfast25 - 17-2-2015 at 11:38

Just saw near the bottom that they offer a two thumpers in series version, was wondering about that. I guess the enrichment effect of a second thumper is probably much smaller than the first?

Two jam jars for the price of one! Triple distillation!

If you put five 'doublers' in do you get 300 % EtOH?

Where's Zomb when we need him?

[Edited on 17-2-2015 by blogfast25]

deltaH - 17-2-2015 at 11:41

Oh god I'm dying of laughter.

I was under the impression that the liquid level in the thumper doesn't keep increasing post start-up, no?

blogfast25 - 17-2-2015 at 11:48

Quote: Originally posted by Molecular Manipulations

Try Gallagher's "Milk of the Gods"

Link?

blogfast25 - 17-2-2015 at 11:50

I was under the impression that the liquid level in the thumper doesn't keep increasing post start-up, no?

But Delta, HOW CAN THAT POSSIBLY BE?? An uncooled pot like that MUST act in part as a condenser, BY DEFINITION, almost!

deltaH - 17-2-2015 at 12:05

I was under the impression that the liquid level in the thumper doesn't keep increasing post start-up, no?

But Delta, HOW CAN THAT POSSIBLY BE?? An uncooled pot like that MUST act in part as a condenser, BY DEFINITION, almost!

In part, but the heat losses to the air is small, it doesn't have a large surface area and it's convective cooling which is also not large, compared to a water cooled condenser that is.

I read http://homedistiller.org/equip/designs/thumper to try to answer this issue of the size of the thumper, they make the point that you don't want it too small because the extra alcohol has to come from the volume of what was originally placed there and as it's depleted, it works worse and worse until it has little effect. That makes sense to me, so yes, that jar does look a little small, but then again, it is recommended to use distillate tails to charge it, which would help to have more alcohol in a smaller volume of course.

There's probably an optimal size born out of experience with these things. I'd say it's probably made as large as the tails generated from distillation from a certain sized rig.

blogfast25 - 17-2-2015 at 12:11

In part, but the heat losses to the air is small, it doesn't have a large surface area and it's convective cooling which is also not large, compared to a water cooled condenser that is.

Totally subjective. What if you use a fairly large copper thumper on a cold night in the Appalachian Mountains?

The point stands: the thumper MUST fill up, slowly or quickly is fairly irrelevant.

There's probably an optimal size born out of experience with these things. I'd say it's probably made as large as the tails generated from distillation from a certain sized rig.

Look at the designs on the Tinkerwebs: there's no real discernable pattern.

[Edited on 17-2-2015 by blogfast25]

deltaH - 17-2-2015 at 12:21

In part, but the heat losses to the air is small, it doesn't have a large surface area and it's convective cooling which is also not large, compared to a water cooled condenser that is.

The point stands: the thumper MUST fill up, slowly or quickly is fairly irrelevant.

[Edited on 17-2-2015 by blogfast25]

I think there need merely be enough room for one run... what's that, a couple of hours for a couple gallon still?

You could also do something exotic, like pipe a tube with a tap to 'relieve' it back into the still periodically during a run and have an easy way of filling it with fresh distillate afterwards. Then you would have true reflux... well the batch-wise equivalent anyhow

blogfast25 - 17-2-2015 at 12:25

That makes sense to me, so yes, that jar does look a little small, but then again, it is recommended to use distillate tails to charge it, which would help to have more alcohol in a smaller volume of course.

Why not put 100 % proof in it? Then claim you're 'doubling'? Could work but not what we're discussing here.

Yep, turn it into a proper refluxer, again: not what we're talking about. Not the thumpy people either...

[Edited on 17-2-2015 by blogfast25]

deltaH - 17-2-2015 at 12:32

The thing is, as I understand it, there's no need for a proper reflux for making 'likker' since it's not that difficult an enrichment based on the phase equilibrium discussed earlier. So really, this seems to be a very simple solution that gets the job done. If so, then hats off :cool:

The only advantage from more trays and employing reflux is you can increase the alcohol recovered because employing a reflux ratio gives you that extra degree of freedom, but that comes at the cost of extra energy consumed to run the boiler, so really that 'ain't free neither'.

Apologies... I feel the need to start speaking 'billy.

blogfast25 - 17-2-2015 at 12:40

delta H:

Of course it's not free, whatever you do. No contest.

Secondary argument (already made to be fair):

If this little trick works, how come you don't read about it in engineering textbooks, journals or even half-decent internet sources (you know, the ones that might feel the need to substantiate things with experimental data)?

I posit it to you that it's for the same reason no decent person would publish anything substantiating the 'HOH' crapola: it DOESN'T WORK!

deltaH - 17-2-2015 at 12:47

"it DOESN'T WORK! "

I'm waiting for the experimental evaluation from you and SM members before calling it, since to me it looks at least plausible.

blogfast25 - 17-2-2015 at 12:56

"it DOESN'T WORK! "

I'm waiting for the experimental evaluation from you and SM members before calling it, since to me it looks at least plausible.

You've not addressed my point though: if it does work why is the information available about it of such abominable quality? Not to mention scarce?

[Edited on 17-2-2015 by blogfast25]

deltaH - 17-2-2015 at 13:09

"it DOESN'T WORK! "

I'm waiting for the experimental evaluation from you and SM members before calling it, since to me it looks at least plausible.

You've not addressed my point though: if it does work why is the information available about it of such abominable quality?

Cause snobbish academics wouldn't touch anything 'billy with a ten foot pole

To be fair though, this is just another way to operate a distillation process, there's probably case specific weird and wonderful setups and tricks employed in industrial columns not necessarily well published, they are just simply different designs and variations on a theme. The toolbox for variation on distillation is vast, you can use re-heaters, pump-arounds and and and... I don't even know half of all the crazy things that can be done and is done in this field. So basically, I think it's not commented on by the greater scientific community because it's application is a bit narrow. It suites 'shining, but really the advantages are not that great out of that context were other means would suit better.

...and maybe there is reliable literature out there somewhere to be unearthed. I doubt the keyword "thumper" would be referenced in the type of literature you're looking for, so in short, it probably is out there somewhere.

blogfast25 - 17-2-2015 at 13:18

[...], it probably is out there somewhere.

A bit like Bertrand Russel's Celestial Teapot?

deltaH - 17-2-2015 at 13:26

I'm trying to dig through patents now, because this sounds like the kind of thing that would have been patented at some point in time. A patent usually publishes some numbers in their 'examples' section.

No luck yet, probably because of the vast wealth of distillation related patents out there and also the funny unnatural language patents use.

[Edited on 17-2-2015 by deltaH]

blogfast25 - 17-2-2015 at 13:32

Cause snobbish academics wouldn't touch anything 'billy with a ten foot pole

Lily-livered librul academics are 'fraid they's gonna beat up by them billys with their baseball bats, for publishing their Appalachian secrets, bro. What goes on in Appalachia stays in Appalachia!

[Edited on 17-2-2015 by blogfast25]

deltaH - 17-2-2015 at 13:44

it's called a double retort:

copper-rum-still-with-double-retort.jpg - 11kB

Notice what appears to be overflow pipes to return liquid to the still :cool:

see here:

http://eatsdrinksandsleeps.com/page/5/

Image looks very old. Apparently standard in the traditional rum making method?

I used google's similar image search and found another in an old book where it also appears to be used but called a rectifier.

See (PS. scroll down):

http://chestofbooks.com/food/beverages/Alcohol-Properties/De...

[Edited on 17-2-2015 by deltaH]

Magpie - 17-2-2015 at 14:09

In reference to the submergence of the vapor pipe from the still: I don't know how much the typical moonshiner submerged the outlet but it would elevate the bp of the wash in the pot above that obtained using atmospheric pressure. 2.3 ft of water submergence is equivalent to 1 psi.

Zombie is likely taking one much needed nap, or he had to go to work, or both. He has been giving his all for science.

[Edited on 17-2-2015 by Magpie]

blogfast25 - 17-2-2015 at 14:25

it's called a double retort:

Notice what appears to be overflow pipes to return liquid to the still :cool:

see here:

http://eatsdrinksandsleeps.com/page/5/

From that link:

Quote:

Alcohol boils as at lower temperature (78.3° C) to water 100° C. So when the pot still is heated, alcoholic vapour will be released before water is, it passes into the low wine retort, a second copper vessel which contains an alcoholic mix of low wines and water. The hot vapour passing through, boils the liquid in the retort, releasing its most volatile components. This vapour is now more concentrated in flavour and is carried through to the high wines retort, where the process is repeated. The vapour is now high strength and is condensed. By adjusting the composition of liquids in the low and high wines retorts, a distiller can create a range of different flavours.

The 'thumpers' are already charged with alcohol.

Eatsdrinksandsleeps, science 101 indeed!

Oh, yes: 'chestofbooks', Zzzzzzz....

Is that all you've got?

[Edited on 17-2-2015 by blogfast25]

blogfast25 - 17-2-2015 at 14:29

In reference to the submergence of the vapor pipe from the still: I don't know how much the typical moonshiner submerged the outlet but it would elevate the bp of the wash in the pot above that obtained using atmospheric pressure. 2.3 ft of water submergence is equivalent to 1 psi.

Zombie is likely taking one much needed nap, or he had to go to work, or both. He has been giving his all for science.

C'mon Magpie, you're grasping at straws. Do you know what the influence of 1 psi on BP is???

Next you'll come up with bubble sizes, surface tension and air humidity!

"... his all for science". I assume there was an emoticon missing there!

[Edited on 17-2-2015 by blogfast25]

Fulmen - 17-2-2015 at 14:30

deltaH: The last link shows a pipe that I interpret as the return flow, making it a full stage. The first one is harder to tell, but there is something there as well.

blogfast25 - 17-2-2015 at 14:39

Quote: Originally posted by Fulmen

deltaH: The last link shows a pipe that I interpret as the return flow, making it a full stage. The first one is harder to tell, but there is something there as well.

Both look exactly the same. But full stages that leak heat unimpeded? The heat loss must cause extra condensation.

More like inefficient refluxers...

[Edited on 17-2-2015 by blogfast25]

Fulmen - 17-2-2015 at 14:59

It's the same principle really. Whether the reflux is controlled by an external condenser and divider or by partial condensation in the stage itself is irrelevant for the principle. It acts like a cooled fractionating column, not unlike what we would set up in the lab.

aga - 17-2-2015 at 15:18

To my simple mind it seems like this :-

Start Condition: Boiling pot & Thumper pot contain e.g 50w% EtOH, equal volumes

Begin heating Boiling pot.

EtOH starts leaving Boiling pot, and instantly condenses in the cooler Thumper pot liquid.

This increases the Thumper pot volume, temperature and w% of EtOH.

Eventually the temperature in the Thumper pot is sufficient for the EtOH in there to begin leaving, to be recovered in the condenser.

The main difference is that the now boiling Thumper liquid has a higher w% of EtOH than the original Boiling pot liquid.

Would anyone here have any experience in Ethanol/water distillation where the w% of the stock liquid has a marked impact on the w% of the distillate in a simple distillation ?

Would a higher concentration of ethanol:water impact in any significant way on the distillate concentration ?

blogfast25 - 17-2-2015 at 15:23

Would anyone here have any experience in Ethanol/water distillation where the w% of the stock liquid has a marked impact on the w% of the distillate in a simple distillation ?

Would a higher concentration of ethanol:water impact in any significant way on the distillate concentration ?

These questions are quite accurately answered by the EtOH/water boiling point/composition diagram, which delta H linked to a few pages higher up.

Here:

http://www.sciencemadness.org/talk/viewthread.php?tid=61566&...

[Edited on 17-2-2015 by blogfast25]

aga - 17-2-2015 at 15:45

Dullard that i am, the graph is a bit incomprehensible, with the X axis labeled 'Y ethanol' and the Y axis unlabelled.

If i understand anything from it, does that mean that you get a bigger w% EtOH change starting from a Low EtOH concentration than you would starting from a High EtOH conc ?

If so, the w% of the Thumper liquid should end up fairly close to that of the end product.

blogfast25 - 17-2-2015 at 16:03

Aga:

x axis is EtOH, y axis is water. The curve relates the vapour composition (higher in EtOH) to the liquid composition (lower in EtOH).

Each 'step' of the 'stairs' shown is 1 single stage distillation (= 1 evaporation + 1 condensation).

Start from a higher EtOH, you end up with a higher EtOH. More 'steps' also means more EtOH.

The number of 'steps' depends on set up: Vigreux = more steps than no Vigreux for example...

[Edited on 18-2-2015 by blogfast25]

Magpie - 17-2-2015 at 16:23

Aga:
x axis is EtOH, y axis is water. The curve relates the vapour composition (higher in EtOH) to the liquid composition (lower in EtOH).

No, I think that the x-axis is "mole fraction ethanol in liquid" and the y-axis is "mole fraction ethanol in vapor." I have this same diagram in my "Principles of Unit Operations" book by Foust et al. It is a vapor-liquid equilibrium (VLE) diagram for the system ethanol-water. deltaH please verify.

One of the often repeated phrases in this discussion is that heating a solution of water and ethanol drives off ethanol as a vapor as if it were only ethanol that was evaporating. Ethanol is never alone in the vapor but is always accompanied by water vapor.

[Edited on 18-2-2015 by Magpie]

aga - 17-2-2015 at 16:25

Oh.

Start with more, get more, just Less % difference.

So if the starting condition was the same in the Boiling pot and the Thumper, then the increased EtOH concentration in the Thumper pot *before* it starts boiling Will give a higher EtOH concentration in the end product, as it will be starting from a higher EtOH conc.

If so, it should end up the case that the Thumper output will have a higher w% than a straight non-Thumping distillation.

blogfast25 - 17-2-2015 at 16:27

Oh.

Start with more, get more, just Less % difference.

So if the starting condition was the same in the Boiling pot and the Thumper, then the increased EtOH concentration in the Thumper pot *before* it starts boiling Will give a higher EtOH concentration in the end product, as it will be starting from a higher EtOH conc.

If so, it should end up the case that the Thumper output will have a higher w% than a straight non-Thumping distillation.

According to Thumper 101, yes. Not according to moi.

Or Fulmen.

My point is simply that that would work if you condensed the primary still pot vapours into the thumper, then externally heated thumpy. That would be 2 distillations.

Not by blowing water-rich primary vapours through it though...

[Edited on 18-2-2015 by blogfast25]

Magpie - 17-2-2015 at 16:42

So if the starting condition was the same in the Boiling pot and the Thumper, then the increased EtOH concentration in the Thumper pot *before* it starts boiling Will give a higher EtOH concentration in the end product, as it will be starting from a higher EtOH conc.

Not quite. The vapor out of the thumper is richer in ethanol than the liquid in the thumper because of the relative volatility of ethanol to water. The thumper is acting as a vapor/liquid equilibrium stage and the increase in ethanol can be determined from the VLE diagram.

Example:

In a perfect equilibrium stage liquid at its bubble-point (at boiling) that is 0.2 mole fraction in ethanol (x-axis) will produce a vapor that is ~0.53 mole fraction in ethanol (y-axis). You can determine this from the VLE diagram I posted in my last post (which I copied from deltaH's post). This is how a fractionation column works.

[Edited on 18-2-2015 by Magpie]

[Edited on 18-2-2015 by Magpie]

blogfast25 - 17-2-2015 at 16:47

You keep forgetting that you're blowing EtOH impoverished primary still vapour into the enriched thumper liquid.

It's not like you're adding dry heat.

aga - 17-2-2015 at 16:47

Erm, after all the EtOH has left the primary pot, it's all in the Thumper pot.

Thumper liquid will now be Hot.

Next the Water vapor will start entering Thumper, driving the distillation in Thumper, and changing the EtOH:Water conc as well.

Sounds like a race against time/conc.

The First distillate from the Thumper should therefore be of a Higher w% than expected from a straight distillation, with the conc steadily decreasing as the heating steam, and the evaporating EtOH reduces the Thumper EtOH conc.

Maybe the 'Great Secret' is that the first distillate out of the Thumper is the 'Good Stuff'.

Squaring the circle, the Laws of Thermodynamics are not violated at all.

Over the entire distillation, the total volume of EtOH collected will be exactly the same Thumper vs Straight distillation.

Exactly When you collect your distillate dictates your EtOH concentration when using a Thumper.

Glad we got that sorted out without all that tedious 'actually doing anything'.

[Edited on 18-2-2015 by aga]

Magpie - 17-2-2015 at 16:52

Aga, I think you have the right idea. Moonshining is a batch process and the boys will shut the still down at a certain point to maximize the product to their specifications.

aga - 17-2-2015 at 16:58

More than that : they developed a Time Function, where they collect distillates at differing Times into the distillations.

Each Timed portion represents a different EtOH concentration.

Heads, Flow and Tails were the billyclue.

Yeehar !

[Edited on 18-2-2015 by aga]

blogfast25 - 17-2-2015 at 17:00

Aga, I think you have the right idea. Moonshining is a batch process and the boys will shut the still down at a certain point to maximize the product to their specifications.

The overwhelming majority of your boys don't actually measure anything. 'Proof' at start and end perhaps, nothing more...

aga - 17-2-2015 at 17:05

Someone mentioned that this could be solved with a can of beer.

I think i just did.

At the very least, the basis for a definitive experiment is now available.

Distillation, EtOH conc of distillate measured say every 10ml or so.

Distillation with Thumper, EtOH conc of distillate measured the same.

Results would show one way or the other what the Thumper does or does not do.

Get on with it !

Magpie - 17-2-2015 at 17:07

You keep forgetting that you're blowing EtOH impoverished primary still vapour into the enriched thumper liquid.

It depends on which part of the batch process you are in. In the latter part you are right and that is likely where the boys will shut down the still.

In the beginning of the distillation the vapor from the pot will be richer in ethanol than the thumper liquid.

blogfast25 - 17-2-2015 at 17:12

In the beginning of the distillation the vapor from the pot will be richer in ethanol than the thumper liquid.

How much richer?

aga - 17-2-2015 at 17:12

S'wot i just said, rehashed.

aga - 17-2-2015 at 17:17

OK.

Seems i just got Brilliant, and the fact is being ignored.

Praise, even Worship please, and lots of of it.

Anyway, enough Said, and 0 actually Done.

There's a possible explanation of Why moonshiners use a 'Thumper', and why they claim it to be a 'doubler' etc, and a way to answer the Original Question.

Experiment.

The data will show whether my Genius Moment was such, or whether Thumper Theory is in fact Hogwash.

blogfast25 - 17-2-2015 at 17:20

Experiment.

It seems to be the only way out of the quagmire. Let this not be another Vietnam.

Magpie - 17-2-2015 at 17:25

How much richer?

I'll get back to you on this (soon). Mrs Magpie just called me for supper. We're having steak flambe (just kidding).

blogfast25 - 17-2-2015 at 17:29

How much richer?

I'll get back to you on this (soon). Mrs Magpie just called me for supper. We're having steak flambe (just kidding).

Lobster Thermidor here. NOT kidding (?)

Give my regards to the lady.

aga - 17-2-2015 at 17:40

Thinking about it, if my drunken theory is right, the Levels of the distillation pot and the thumper are irrelevant : they need not be at the same height at all.

A quick search on moonshine thumpers found a few images of 'stills where the thumper pot is suspended in the air, above the output of the 'still pot.

Heating of the Thumper should also be undesireable, as you'd want as much of the EtOH from the 'still pot to reach it, and condense in there before Thumper starts boiling, which rules out thumper heating being desirable.

Crowfjord - 17-2-2015 at 17:54

How do you guys plan on measuring ethanol concentration in your experiments? Depending on how small of a scale you're working with, it might be too little for a hydrometer.

I think I might join in on conducting an experiment. Maybe. I've been considering making some rum the past few weeks anyway.

blogfast25 - 17-2-2015 at 17:56

Quote: Originally posted by Crowfjord

How do you guys plan on measuring ethanol concentration in your experiments? Depending on how small of a scale you're working with, it might be too little for a hydrometer.

I think I might join in on conducting an experiment. Maybe. I've been considering making some rum the past few weeks anyway.

We're looking into refractometry. Very small sample only needed. But we need to test that properly for accuracy and repeatability.

aga - 17-2-2015 at 18:02

That'd work better than titrations.

From experience, EtOH titrations on 100s of samples would take quite a while ...

Edit:

A quick look on ebay for 'alcohol refractometer' turns up many results, and very affordable too.

I think i'll get one.

The actual accuracy would not be too important, as it would be a Comparison of straight distilled w% vs thumper distilled w%.

[Edited on 18-2-2015 by aga]

blogfast25 - 17-2-2015 at 18:21

The actual accuracy would not be too important, as it would be a Comparison of straight distilled w% vs thumper distilled w%.

Correct. The absolute values are less important. Relative but statistically relevant numbers are far more important.

Absolute Values opens a can of worms like the use of Absolute Material Standards. Not easy. Big Science territory.

[Edited on 18-2-2015 by blogfast25]

Zombie - 17-2-2015 at 18:54

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.

Sorry, I got held up, making up for time lost yesterday.

I just wanted to catch up on the thread, and I'm still reading.

The first part. I think insulating will be ok. Keeping the vapor HOT is the key to how a thumper works. It is after-all the power source (hot vapor).
If it is NOT hot enough the result will be the thumper will fill, and not deliver product out so that will be obvious.

Second, I can't say that Grav. wil / wil not be an issue. I run my thump below the fluid level of the boiler, and for the sake of replicating what I know to work, that is the basis.

The reason for minimum PC cooling is it is the only way to be sure the boiler is heated at the correct settings.
You can heat the boiler on the sun, and a pc can knock it down but you will be evaporating too much water, and thereby negating the reason for doing this in the first place.
Minimum PC cooling to reduce vapor is a mandatory requirement in Whiskey making, and this IS what we are doing.

You will have a boiler / 1/2 size thumper. The boiler should be 3/4 full, and the thumper 1/2 full.

I will avoid answering all the speculative stuff, and only the Tech. stuff till I catch up on the thread.

Zombie - 17-2-2015 at 18:56

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.

This was the "free (+)" energy I refereed to in the beginning.

blogfast25 - 17-2-2015 at 19:01

You will have a boiler / 1/2 size thumper. The boiler should be 3/4 full, and the thumper 1/2 full.

Ok, welcome back.

No gripes except with that quote. We'll be using say a V (volume) pot still and a V/2 (half that volume) thumper. If the total feedstock was say A, how should we allocate that over both? Example: 75 % in pot still, 25 % in thumper?

It'll be a small set up, probably 500 ml pot still, 250 ml thumper. Insulation on the primary vapour line, slow distillation.

Final distillate condensing will not interfere with anything, I guarantee you that.

Set up will be revealed before any distillations take place.

[Edited on 18-2-2015 by blogfast25]

Zombie - 17-2-2015 at 19:04

This is exactly right. The thumper will follow the heat curve of the boiler, and that makes it imperative to maintain the product stream as the indicator of power management.
Too little power, and the thumper fills.
Too much power, and you are spewing unwanted water vapor, thereby negating the purpose.

Magpie - 17-2-2015 at 19:06