What Two Thumpers Can Do

[Bolverk]

Hey Haggy,

After playing with your thumper calculator I just don't think the juice is worth the squeeze on this tall skinny thumper idea. I just won't get the pressures I want to justify the cost of the build.

[haggy]

Bolverk
OK, it is your dime.

But here are the thumper calculations I just completed. Maybe you will change your mind.

And before this, to make the charge to the two thumpers, you need to do two stripping runs with the 8% wash, then take the low wines from both and do another strip to get the material to use to make up the 22% and 40% ABV thumper charges.

Temperatures seem to be high enough to bring out some of the esters for the enhanced flavor. And the thumpers do not fill up much, only during their heating up. You have to go deep into the run ( all 6.5 hours ) to get to the heavier esters.

haggy

P.S. I saw your continuous distillation idea. Cannot comment on that now, I will look at it.

[Bolverk]

Thanks Haggy, I appreciate you running this... this idea may not be as dead as I thought.

[goose eye]

You can lite a wick under your doublein keg to get it close to hot then rake the coals back. Shoot them thangs if that what you lookin.
Good to see folks pushin know how but every now and again just light the wick and let it be. Like one ole boy said help you get your chi right

So I'm tole

[haggy]

Kareltje has sent me data for several runs that he made with two thumpers. This was good complete data where in addition to the ABV and amount made vs run time, he also measured the amount remaining in the thumpers at the end of the run. I had to modify slightly the calculation of the heat losses in each thumper to agree with the amount remaining data.

A typical run was a One and Done run with 10.3% ABV wash in the boiler and both thumpers. The boiler had a 14 Liter wash charge and the 10 liter thumpers about 2 liters wash each. The boiler power was adjusted to 520 Watts which fit the run data. The Watts used were less than the data because of heat losses with the gas burner system.

The updated calculations agreed with the ABV and amount distilled data,

The volume in both thumpers increased with run time. Calculation results of the volume remaining in the thumpers are close to the data after adjusting the heat loss calculations of both thumpers. Both thumpers started with about 2 liters and ended up with about the same volume, 4 liters and 4.2 liters.

The initial distillate ABV of the data was a little higher than expected / calculated. I presume that colder equipment and lines at the start gave extra passive reflux and raised the ABV.

This One and Done run also made a good amount of hearts, about 2 liters at 63% ABV. Several other runs with different input data were studied and gave similar results.

So, with this new data, I now have a more proven and more reliable double thumper calculator.
Thanks, Kareltje


Then I was trying different inputs and found something " very interesting ".

Instead of putting wash in the boiler, I tried 30 % ABV "low wines" in the boiler and wash in the thumpers.

The resulting distillate ABV was high ( 80% ) and very steady at this level for a long time, 5 hours. Something like we see in a reflux column run. Then the ABV gradually decreased. A lot of Hearts were made.

Here are details of this type of run. We will start with 14 gal of 30% ABV in the boiler and 2 gal of 10% wash in both thumpers. The boiler power will be steady at 2000 Watts.

Input Data

image.png (11.87 KiB) Viewed 1111 times

Results

You can see the steady distillate ABV and its gradual drop and very steady cumulative product ABV over the entire run time.

Estimated Hearts made were about 4.6 gal at 74% ABV with Tails starting at about 40% ABV out the spout at 450 minutes run time from the start of the pot boiling.

The volume in the both thumpers rose initially from 2 gal up to 3.6 gal, then were steady ( almost flat ) for most of the run time. A Good Result also.

The liquid ABV in the last thumper has a gradual rise, then steady, then a gradual drop. This vaporizes to give the steady distillate ABV.

So, if you have two thumpers, give this concept a try and report on it. Maybe it is a very good way to run the two thumper setup. Much like a Spirit run in a pot still with two extra stages after the pot.


haggy

[haggy]

In a recent post, rubberduck71 reported on two runs he made with his two thumper still. Here is a link to that post : viewtopic.php?t=90521

Both runs had 25% abv in Thumper 1 and 40% abv in Thumper 2 and low initial charges. The July 3 run had an 8% abv wash in the pot, the July 24 run had the wash plus feints in the pot. The objective was to make a high distillate abv product and extend that abv for a long run time. Both runs did this well.

The reason this works is that both thumpers have small charges so incoming vapor when condensed will initially raise the liquid abvs and keep them high. The Thumper 2 liquid abv is high initially and stays high for a while then decreases slowly during the run. So the vapor abv out of Thumper 2 is high.

Here is my Excel Pot and Two Thumper simulation of the July 24 run. A 700 watt power value ( less than the actual setting ) fit the run distillate abv and rate data well. Thumper heat losses were 46% and 42%. When tails were seen, the pot power was increased to 1200 watts, then the abv dropped fast.

Input Data

image.png (12.06 KiB) Viewed 1022 times

Vapor and Thumper Distillate ABV

Thumper Volume and Distillate Gal

Pot and Thumpers Liquid ABV

So, this run by rubberduck71 proved the objective stated above. Go to the link to see details of the runs and the amount of hearts made in the runs.

[haggy]

Some ( well-known ? ) facts about thumpers are:

1. Thumpers that are WELL INSULATED:
Have less heat losses
Have more product vapor distillate - good
Have less liquid fill up of the thumper - good
Require less pot heating (gas) - good

And conversely,
Thumpers UNINSULATED have more heat loss, less product volume and more liquid fill. This could lead to more heat ( gas) that is needed to get a desired product rate.


2. Stills with Two Thumpers can do a One n Done Run using only Wash
Barrel strength hearts product ( 62.5% ABV or greater ) can be made in one run using > 9% abv wash in the boiler and in both thumpers.


I have seen these two facts demonstrated in several of Kareltje's previous two thumper runs and now in some recent two thumper runs. He used only a wash in the boiler and also in the two thumpers. He sent me this recent data for three different runs and agreed to me posting it.

His thumpers were well insulated and had low heat losses ( 25% to 30% ). I fit my two thumper calculation model to his data by varying the amount of heat loss in each thumper. Thumper 1 was lower heat loss than Thumper 2. He measured the volume in the thumpers after the run was completed and the ABV and amount of distillate product during the run. The model results agreed well with the data.


Details of a One n Done Run using Wash only
Here is an example of one of the three recent runs. The boiler had 14 liters of 12% abv TFFV wash and was run at about 510 watts heating. Both of the 10 liter thumpers had 3 liters charge of the 12% abv TFFV wash at the start of the run.

Here are the calculated and data abv results during the run:

Here are each thumpers volume and amount of the distillate and data during the run:

The volume of the thumpers did not increase too much after their initial heat up. Run time starts when the boiler starts boiling and sending vapor over to the first thumper to heat it up. Tails started at about 45% abv out the spout, 290 minutes run time. The thumpers each started at 3 liters volume and rose to about 4.8 and 5 liters volume at the end of the run ( 440 minutes ).

Also, a good amount of hearts, about 2.3 Liters at 70% abv (above barrel strength) was made. The alcohol yield of the hearts based on total alcohol charged was about 67%, a very good result.

There were also two other very similar runs, only the amount of wash in the thumpers was varied, 2L + 4L and 4L + 2L. The run results were very similar. They were also One n Done runs. My two thumper calculator using the same heat losses fit the abv and distillate amount of the other two runs just as well.

So, these three double thumper runs demonstrated the above thumper facts very well and helped confirm the validity of the two thumper calculations.

haggy

[zach]

I recently acquired 5 gallon milk can that I decided to use as a second thumper. This thumper has connections for an electric heating element. It also has 4" connection on top. I have sieve plates , LM or VM head that I could place on top of the thumper.

I use steam to strip wine/ pomace or all grain ferments. I'm trying to decide how to operate this new configuration. My goal is for a one and done with my steam stripper with the 2nd thumper.

I use the simulator on hobbybrennen.ch to evaluate my options.

My initial conditions look like this:

If I run the second thumper with minimal reflux and stop at roughly 49% abv on the outlet the simulator predicts the following;

If I run the second thumper with internal heating element (500 watts) and 50% reflux and stop collecting product at 49% abv on the outlet the simulator predicts the following:

I added un-insulated riser piping to generate the reflux in the calculator. Without the heating element the reflux fills 2nd thumper prior to stripping the first thumper.

Below 50% abv I would start collecting feints to fill the second thumper for the next run.

One advantage of the heating and refluxing the 2nd thumper is more ethanol recovery. With brandy I hope to keep the tails out of my collection, and believe I could control the power and reflux for a cleaner product with higher abv. With whisky I kind of like a little bit of tails so the heat and reflux on the thumper might not be used.

Does anyone else use steam stripper run with second thumper?

[Bolverk]

I've got the steam boiler and a 60 boiler (thumper) and 30 thumper

Id be more inclined to do the first way you said.

I remember reading what made a double retort work correctly was the temp delta from one thumper to the next and the stacking of ABVs... I'd have to go reread that post to get more detailed. The big take away was that it should all be fed off the power from the main boiler.

I also would run as little reflux as I could but this is entirely personal, it depends what you like to drink. I like funk, Id run that down to about 55% and probably add some of those deeper grain heavy tails to my final cut.

I'm really into the idea of reproducing some old pre-pro style whiskeys. the method they used was steam power into new beer and singlings (low wines) in the thumper. My last run was really good, unlike any rye I've ever tasted.

[shadylane]

Is this enough pressure and operating temperature increase to make a difference in the product?

I can't answer that question.
First, I'd have to replicate the recipe and 2-thumper rum still.
Then do dozens of runs so the fractions used for heads and tails are stable.
Last comes the hard part, making adjustments needed to get the formulas to agree with reality.

Damn, the more I look at and rethink what I said the grumpier it sounds.

[Hügelwilli]

zach,

my comment about your comparison with the thumper simulator:
The difference you get comes mainly from your decision to stop collecting hearts at 49%abv vapor. In the simulation with the activated heating element you have much more reflux above the second thumper than in the other simulation. This rises the abv and therefore extends your hearts, when you cut strictly based on abv.

Your calculated hearts yield of 85.5% of the total alcohol looks much too high for me. Normally you have to end the hearts much earlier. Also the 77.7% of the other simulation is perhaps too high.

[zach]

Thanks Bolverk & Hugelwilli for your comments.

In reality I will make cuts on taste, like any other spirit run, but for simulation I had to have a final condition.

The initial conditions I posted yesterday were based on a 12% wine in the first thumper and I probably overcharged the 2nd thumper which resulted in high recovery rate.

I ran another simulation based on a 7% whisky wash and less low wines in the 2nd thumper resulting in a much lower recovery rate.

Initial conditions

Final condition with no heat/reflux on 2nd thumper

Final condition with heat & reflux on 2nd thumper

[Bolverk]

I like the "Final condition with no heat/reflux on 2nd thumper", that's what I'd do...

[Hügelwilli]

In reality I will make cuts on taste, like any other spirit run, but for simulation I had to have a final condition.

zach,

But "final condition" means the possible cut point?
If you use reflux you will end the hearts at a higher current abv than if you don't use reflux. That's why I think your comparison could be better. For example end the hearts in both simulations after you have collected 70% of the total alcohol amount. I think this would be more realistic.

To use reflux to extend the hearts yield is something many members here would not recommend.

[haggy]

zach,

You said:

One advantage of the heating and refluxing the 2nd thumper is more ethanol recovery. With brandy I hope to keep the tails out of my collection, and believe I could control the power and reflux for a cleaner product with higher abv. With whisky I kind of like a little bit of tails so the heat and reflux on the thumper might not be used.

That is correct, the thumper 2 refluxing part. But it is really kind of obvious. The higher product abv due to more reflux will give more alcohol in the product over the entire run. The need for heating is not so much, especially if a low thumper 2 fill is used. A low thumper 2 fill is desired since it will result in a higher liquid and product abv.

I looked at your last case, 7% abv in the Thumper 1, with my pot and two thumper calculator and tried to get a valid comparison of the still with low thumper 2 refluxing and with high thumper 2 refluxing. My input data is the amount of heat loss in each thumper. A high heat loss would be due to no insulation or with a riser refluxing.

All the same input charges of your last 7% run were used in these calcs. My first case with insulation has a heat loss of about 22% in each thumper. The second case will keep the same 22% heat loss in Thumper 1 and have about 42% heat loss in Thumper 2.

Both cases were run to and through much of the tails. Then a calculation is made for the amount and abv of the hearts. The amount of heads is first estimated, then the rest of the product down to the start of the tails ( at 40% abv out the spout ) is hearts.

So, here are results of the case with insulation and no riser. The 2nd paragraph gives a breakdown of the expected heads, hearts and tails.

You see that 5.13 L of hearts at 51%abv was made. Some other information is also given. You see the heat losses are about the same 22% in both thumpers.
________________________________________________________________

Here are results of the case with no insulation (and a riser) in Thumper 2 giving a high heat loss of 43%. Again, check out the 2nd paragraph.

In this case, about 5.6 L of hearts at 59% abv was made. That works out to about 26% more ethanol recovery with the no insulation / riser case, confirming your observation.

_________________________________________________________________

Here are some more results so you can see a complete picture of the runs. The insulated low heat loss case is first and the no insulation/riser case is last.

In addition to more ethanol recovery, you would make a cleaner product and keep more tails out of the product in a two thumper still with high thumper 2 heat loss via no insulation or riser refluxing. You could also follow an insulated thumper 2 with a reflux column and get an even cleaner, higher product abv and less tails.

haggy

[zach]

Thanks haggy for running the numbers !

How are the percentages of heads/hearts/tails determined in your calculations?

[zach]

To use reflux to extend the hearts yield is something many members here would not recommend.

Hugelwilli

Not trying to be confrontational, but why? I see a large number of hybrid pot stills with short offset columns being used in industry. Doesn't this provide the ability to separate fractions slightly better and keep more of the hearts?

[haggy]

zach,
You and many others might be sorry you asked this:

My calculation of heads, hearts and tails - best calc that I did for this version is this - it is based on studying many posts:

1. Calculate the total amount of alcohol charged = liters L of alc
2. 20% of that is the alcohol in the heads - volalcheads - in liters
3. Headabv = cuml abv after 2 steps of thumper 2 = abvheads
4. Heads L volume = volalcheads / abvheads

1. From the ongoing run calcs - you know the total volume made when abv out the spout goes less than 40% abv - call this the start of tails - some do more than 40%, some less so we have - Tails start L Volume
2. Hearts L volume = Heads L Volume - Tails start L Volume
3. Tails L volume = Final Total volume - Tails start L Volume


So now we have the volume of the three cuts and heads abv. The other abv's are more complicated, and not exact, but the best I could estimate at the time:

1. Estimate the Tails abv - ? ( tougher to do - did this equation ) =
( 40 + abv out spout at end ) /2 = Tailsabv
this can be improved on - with a more detailed calcs
2. Calc the total ethanol L out = Final Total alc L out * cuml abv out
3. Calc the ethanol L in the heads and tails - since we now know the heads and tails volume and abv
4. Ethanol in the hearts = Total ethanol L out - ethanol L in the heads and tails
5. Heartsabv = Ethanol L in the hearts / hearts L volume

If I run a case and stop the run at the end of hearts ( when tails start when abv out the spout goes under 40% ), so no tails are made. Then look at the calc of hearts abv, I get about the same result as this calc above when run went into the tails. So calc is ok but could be improved by better estimating the tails abv. Also, I could let the user decide how much abv out the spout to start the tails.

I did a stop the run at the 40% out the spout with the insulated first case above and got 2.4 L of alcohol out vs 2.62 L before above. So not exactly the same.

I did a stop the run at the 40% out the spout with the uninsulated second case above and got 3.2 L of alcohol out vs 3.3 L before above. So not exactly the same, but close.

The comparison : 3.2 / 2.4 = 1.33 - so, 33% more alcohol this time. We get the same conclusion as above.

zach, so due to your question, I may go back and do a more exact job of estimating the Tails abv. PM me if you have more questions on the calcs.

haggy

[zach]

Wow haggy! Thank you for the explanation.

With your model, the first 20% of the ethanol in the ferment is consider heads.

Then when product condenser outlet reaches 40% abv, the remaining collection is tails.

The volume collected between the two cut points is your hearts. I can see how someone who has a consistent process can make cuts by volume.

Sometimes I detect tails at 50% abv at the spout. I might choose to keep these or not depending on what I'm making, but I think the 40% abv is the right order of magnitude. We all keep some of the heads and tails unless making a neutral spirit.

[haggy]

Yeah, thanks

I could make it user friendly if someone wants to use this Two Thumper browser file.

Could have an input data on amount of heads - initial value at 20% of total alcohol

And an input data on when tails start - initial value at 40% out the product condenser

But, in reality, Cuts are usually done by taste and smell - this is just a guideline

[Hügelwilli]

To use reflux to extend the hearts yield is something many members here would not recommend.

Hugelwilli

Not trying to be confrontational, but why? I see a large number of hybrid pot stills with short offset columns being used in industry. Doesn't this provide the ability to separate fractions slightly better and keep more of the hearts?

zach,
when you distill with reflux, you hold down the tails very long. But at this point almost all good flavors are already collected. This means, when you extend your hearts this way, you collect spirit with only few good flavors, a few bad flavors and much tasteless alcohol. Not really bad stuff, but much less quality than before. At the end you dilute good product with less good product by extending the heart cut.

[Twisted Brick]

Not trying to be confrontational, but why? I see a large number of hybrid pot stills with short offset columns being used in industry. Doesn't this provide the ability to separate fractions slightly better and keep more of the hearts?

zach,
when you distill with reflux, you hold down the tails very long. But at this point almost all good flavors are already collected. This means, when you extend your hearts this way, you collect spirit with only few good flavors, a few bad flavors and much tasteless alcohol. Not really bad stuff, but much less quality than before. At the end you dilute good product with less good product by extending the heart cut.

Great point. There's a reason the humble pot still has remained the quintessential tool for flavored products for ages.

Our best booze isn't comprised of just hearts, which flavor-wise are sorta benign. To me, the objective is to stretch out the two 'flavor' zones in the pot still curve during distillation (skip messing with the hearts) to help define your spirit flavor profile. This will extend the range of each cut area so you can choose each cut point depending on your mood and aging method. Of course the length (depth?) of these zones will be different for each distiller.

Some may disagree, but a thumper adds a single (and/or half) distillation which by increasing takeoff ABV compresses the ethanol fractions of the run to the heads end, essentially shortening the pot still curve, instead of stretching it out.