Is the Thumper really a second distillation

ben_2

Hello everyone,

I have an interesting topic for discussion. We all know how distillation works. You boil a liquid and the lighter parts evaporate earlier and the heavier later. Then we liquify the vapour and get a solution of purer content. Double distillation is just as easy. You heat the liquid from the first still and do the same process over again.

Now here comes the thumper. From what I have learned the tumper is a still that is not fed by the liquid from the first still, but the vapour from the first still. Because the flow of column stills is not very constant the vapour hits the walls of the still in regular intervals and does a thumping noise.

But wait! I distillation not defined as vaporizing a liquid and liquifing it again. A column still thumper combination does this only once. The question that we have to ask us is:
Is the thumper really a second distillation?
and
Does that matter, if the outcome tastes good?

Marko_I

Never heard of "thumper" before, but found this:
http://science.howstuffworks.com/innovation/edible-innovations/moonshine2.htm
"Some moonshiners use a thump keg, which is simply a heated barrel into which the steam is forced. Some solid material from the mash usually comes along with the steam, so the thump keg, so named for the thumping sound the bits of mash make when they drop into the barrel, re-evaporates the alcohol, filtering out the mash. If a moonshiner wants to make his or her alcohol extra potent, he or she might "charge" the thump keg -- add undistilled mash or a few gallons of alcohol into the keg so the steam picks up extra alcohol vapor on its way to the worm box."

According to conversations in other forums, thumpers seem to be kind of outdated, not much effect but many problems.

ben_2

"Marko_I" wrote:
According to conversations in other forums, thumpers seem to be kind of outdated, not much effect but many problems.

Heaven Hill still uses a Thumper. Unfortunately I just found this out after I did the visit to the distillery.

[Deleted User]

As I understand it, the vapor from the column distillation is injected directly into the liquid contained in the thumper. As the vapor (bubbles) rises up through the liquid in the thumper, it is cooled and goes back into liquid form. The alcohol concentration and temperature of the liquid increase, and the alcohol that boils off is at a higher abv than what came out of the column still. For this to work the liquid in the thumper has to have a fairly high alcohol content to start the process. I'm no engineer, but this would seem to be a very efficient way to get a second distillation without adding any energy to the process.