Thumper advice .

[Shayne]

Using a 15 gallon milkcan set up attached to a narrow thumper from brewhause , the thumper is filled about half way with same mash in the main vessel. Right at start up as the heat starts to I guess create pressure most of the contents of the thumper are expelled leaving it about 1/4 full . 
 

‘’question is , is that enough for the thumper to do its job ? First time I’ve used it as there was an issue with quality and took time going back and forth across the ocean wide . 

[SlickFloss]

Don't use mash in the thumper use finished distillate or wines, it can either charge itself or you can use from previous run

[DrDistillation]

I'd say it depends if you are doing a stripping or spirit run.  Dirty mash in the thumper during a strip run so it won't burn/scorch like it might in the boiler with direct heat.

Then if using the thumper during the spirit run, load it with low wines/feints from previous runs.

You can use a thumper a number of different ways.

[SlickFloss]

I don't think a thumper is a great tool to use for stripping, first I don't like the amount of energy you will put into the run with your intention being a quick strip. Second, kicking up your proof on a stripping run just takes out flavors for you to fractionate for yourself later, grandaddy used to tell me flavors in the water if you strip it all out you can't access it later, thats not technical or academic quotation but its been a great guiding principle for me. Plus less dilution later which is another input cost. You're stripping water out to dilute and put it back in later. In a factory with city water and the ability to price however I want thats not as much of a concern anymore, but in the woods where efficiency is king and clean brew water is a precious commodity, you'd lose a hand for it.

[DrDistillation]

However if you are using a thumper for the purpose of being able to ferment on the grain and distill it then you are GETTING flavors this way, not loosing them.  You're able to get more flavor as well as not lose alcohol from discarded grains.  With a thumper you can still run down low for fantastic flavor down to the 1 to 2% ABV (left in boiler) where lots of flavor resides but most people stop far short of, thinking they are wasting energy (but missing out on fantastic flavor).

On a strip it's done quick and using a thumper of good size adds another benefit in that it allows you to strip more per run.  From the standpoint of the op he could for example do 2 strip runs using the thumper and likely have enough to fill his boiler with low wines.  Thus the energy spent on 2 strip runs with thumper vs 3 typical strip runs without thumper will almost certainly use less energy as well.

The spirit run could then be done without the thumper or could be used with feints from a previous run to again bring over more flavor.

So depending how you use the thumper you can add, not remove flavors.

Not sure what the dilution part is about as you would not be adding water back later during the distillation process.  Matter of fact, you can hold back the "sweat water" to use specifically to dilute the distilled product back down to cask strength adding yet more flavor in.  You can even "oak" some sweat water to use for dilution after oaking is done as well.  This would be impractical in commercial distillation but for the home distiller is pretty easy to do.

Home distillers have it nice from the standpoint that an extra buck per run for electric is meaningless if it helps to produce a better product for them.  Same with cleaning.  A 7.5 gallon thumper is easy to take out side and house down to clean.  A lot of things not practical to do in a big distillery are easy to do at the home/hobby level and can help to produce better spirits.

[Shayne]

Appreciate the replies guys . 
 

First time I had the thumper run dry and the main show didn’t do anything . The second try something similar happened . So I removed the thumper and just added two sections of my column set up one with a plate and one section stuffed with copper mesh . And ran a stripping run like that . 
 

“With a thumper you can still run down low for fantastic flavor down to the 1 to 2% ABV (left in boiler) where lots of flavor resides but most people stop far short of, thinking they are wasting energy (but missing out on fantastic flavor).

you can go this low ?

I have not had any luck so far with the thumper . My goal is flavor as ending up with neutral flavors is a waste of effort and ingredients. 
 

 

 

24 minutes ago, DrDistillation said:

 

[DrDistillation]

Start your thumper about half full of either mash or low wines and it really can't run dry assuming it's just a thumper and you haven't added a heat source to the thumper (don't want to do this).

BTW, you can't judge if it ran dry looking at it later because as your boiler cools down it will "suck back" juice from the thumper as the pressure changes in the boiler as it cools off.  The way to stop this is to have a break or ability to open the pipe between the boiler and thumper and vent to the atmosphere.  Typically this is done with a vent in the pipe of the boiler itself. This is always a good idea but with 2 SS kegs you're boiler won't collapse from pressure as it's pretty strong.   If you use tri-clamps you can throw on gloves to handle the hot pipe and undo/break a pipe to prevent the "suck back" and get a true visual of what is left in the thumper.

To answer your question, you can go very deep in the strip run until your alcohol meter shows 0 coming out of the still.  Realistically the sweat water I mentioned is usually about 5% ABV as measured at the parrot/alcohol meter  and your temp is 210 to 212F or 99/100C and basically just water left in the boiler while you drive what ever vapor is left in the column/riser out that still has some alcohol in it.  So test the taste of this down low and see if it's worth keeping for each new spirit you make.  Otherwise just do the math to see where the trade off of energy vs alcohol produced is worth it.  A sugar wash is easy on your time and may not be worth running down past 15% coming off the still but a hard to sparge or higher cost grain mash is worth getting the most out of especially if it's just an electricity cost and not your time/work.  Only you can decide this but if you get "something" useful from the strip run like sweat water that you can't get otherwise then it adds to your product if used wisely.

Certain spirits produce sweat water worth using and some don't. I wouldn't bother with a bourbon mash but would with a 100% malted barley mash.  With a Rum you can get some good oils down low that you'll want especially if trying to make "funky" rum or Jamaican style rum..  With a still your size it's worth experimenting as the difference in heating what you have left in the boiler is likely under a buck in costs which is nothing for a hobby/experimentation.

I've got a test system similar to yours which is a 26 gallon boiler and 15.5 gallon 1/2 keg to use as a thumper.  Basically exactly twice your size so I know the runs well.

[SlickFloss]

DD: I have never and would never run as you describe. Not saying you can't or don't do it successfully but I don't and would never even try. I originally was going to respond to all the things you said, but deleted it.

OP: Sounds like you had some success omitting the thumper for the stripping run, but what you're doing is still not the best if what you're looking for is flavor. What type of spirit are you trying to make? The set up you have described can be modified to be more intelligent for a whiskey/rum stripping run if thats what you're doing. When you run with that set up you're stripping and applying reflux, which is going to have flavor consequences. What proof do you pull at running your strip as described? 

 

Lets go back to my original advice. What if we used low wines in the thumper.

Edited June 24, 2020 by SlickFloss
Clarity

[DrDistillation]

Slickfloss, I know 5 or 6 different ways to use them to help with distillation.  However anymore I think thumpers have fallen out of favor with packed columns and plates being easily used or doublers more in fashion at commercial distillers.  Being able to control energy very easily these days the other advantages of thumpers is also diminished.

I'd love to hear your comments that you deleted and it surely wouldn't offend me in any way.  This is the way we all learn!

With that said, the only real use of thumpers I do anymore is to put the grains in them for a fast strip run that is crazy smeared and fully flavorful, but most of the stuff I personally make these days is fermented off grain so...

[Shayne]

Right now I’m on sour mash . I am pulling really high 93* since I was using one downer plate and some copper mesh in the two sections I didn’t think it would be too much of a reflux guess I was wrong . In anycase I’m not getting the flavor I’m looking for . And yeah rum is another one . All I really make is stuff a teenager would like for a spodie party . Wife used most of my old stock as hand sanitizer 😹

[DrDistillation]

Well, you really answered your own question about taste.  At that high an ABV off the still you aren't going to have much taste left.  You need to get that way down for a whiskey.

For a pot still style run I'd strip fast and down to nothing left and you should have an ABV of 25%-28% or so in the low wines.  This would allow you're spirit run to produce hearts right around the 160 proof mark and will slowly drop during the run.  Tails will then be somewhere in the 130 to 110 proof range when they come over depending on grains and how clean your ferment was.

After blending take your left over heads and tails and throw them into a feints container and mix them in with your low wines on the next spirit run of the same spirit.  The combination of feints, sour mash and lower proof off the still should get you the flavors you're looking for.

[JustAndy]

It sounds like you aren't using a commercial still, please make sure you have an appropriate pressure release valves and safe discharge piping, especially if you are running mash in the thumper. 

[Al The Chemist]

Jumping in 4 years late on this one. @DrDistillation, as to your comment of thumpers falling out of favor with the advent of bubble plats. If you are going purely for a higher ABV off the bat I’d agree there. Though for things like Rum for instance, where you want a secondary reaction chamber for esterification with a lower water content. Or any other flavor infusion phase that is not botanical, I really can’t find any other solution besides a thumper.  

Would be curious to hear more of your thoughts on this. I’ve tried many different types of still configuration for Rum (without a thumper) and have found that even multiple pot distillation is not amazing. The plates separate the esters too far into heads and tails and most of the ester have an evaporation temp either above or below ethanol.  

@JustAndy, do you have any additional information about the pressure buildups for different amount and height of fluids?  I am looking into building a vertical thumper for a 3kw 10gal boiler and I don’t want to scale things wrong and over pressurize.

[Bolverk]

14 hours ago, Al The Chemist said:

do you have any additional information about the pressure buildups for different amount and height of fluids?  I am looking into building a vertical thumper for a 3kw 10gal boiler and I don’t want to scale things wrong and over pressurize.

Not Andy,  but here's a good online calculator I found.

https://www.convertunits.com/from/psi/to/foot+of+water

 

 

[Al The Chemist]

Thanks @Bolverk 

 

[Al The Chemist]

I've heard mention of people charging a thumper with backset combined with deep tails. Seems to me like that will not have enough alcohol content to do the trick in the thumper. I guess the idea was to try and “infuse” more flavor into a rum. Was curious to hear your thoughts. 

[Bolverk]

I'd put the backset/dunder in the boiler vs the thumper. The volatile acids will carry over from the boiler to the thumper, from there esterfy and then carry over into the distillate. I think the dunder in the thumper would carry over too many undesirables.

Too much water in my opinion. If you mixed some deep tails and high tails you could have more alcohol diversity to create more interesting esters, but in my experience, you want to keep the ABV of thumper above 40-45% for successful esterification.

 

Fun cousins process experiment...

Take your lees (the thumper stillage), add lime (CaO) until you cant desolve any more in the liquid. Then reduce that down until it's just power. This is going to be your "lime salts" or "acid salts" really its calcified carboxylic acids. Then on your next batch add 10% of the salts by weight to your tails alcohol (for the thumper), add sulfuric acid until the esters bloom. Let this sit for 24 hours before using. 

[Al The Chemist]

Makes sense, thanks!