manifolding water heat to heat a still ?

[freebear]

ok im thinking on using my outside wood boiler to heat my still i have a continues supply of 170 to 180 degree water i want to manifold it to the side of a still like it is manifold to the side of my water heater for the house as im thinking it should work goodbut thaughts and working good can be two differnt things without as much info you can get

has anybody toyed with something like this?

any input would be helpful before i get to much farther into this

[Samohon]

Welcome to the boards freebear...

Do you mean to have the hot water pipes 180F (82°C) go through the side of your still boiler to heat the wash..?

This processes uses steam in the still houses in Scotland, US and elswhere to boil the wash...

This is very doable with water but the temps given, IMO, would have to be higher...
Then you have the problem of thermal transfer of the water, how many degrees will it cool down before reaching your boiler...

Hope this shines a light somewhere....

[myles]

I thought about this too, but as samohon implies the issue is the thermal gradient. You won't get your wash up to 86 deg for example by using water at 82 degrees. Even if you took your hot water and boiled it before use the temperature gradient is still a bit low.

Just as an example for you have a look at this. This was heating 22 litres of plain water in a glycol filled double boiler just to test the thermal transfer rates. Monitored bath and wash temperatures and took the bath up to 120 degC and then turned the power off. Both graphs show temp in degC against time in minutes.



This is a typical run with 25 litres wash in the boiler monitoring bath temperature and vapour temperature in the pot.

[Samohon]

Yeah, that was my point exactly myles. The only other way around this issue would be a constant steamed heat source as in the diagram above.
Again, with water piped through the boiler, an adjustable temp would be required to make proper cuts...
The steam coils in commercial pot stills are temp adjustable and therefore proven to work...

Maybe the boiler could be brought to temp by electric/gas, then temps within the water pipes maintained to run the still, but for that, I doubt that a good thermal transfer could be maintained from source to boiler...

Nice though, but it just wont work at that temp...

Hope this helps man...

[freebear]

i was thinking to have a 750 watt element to heat it to the boil point the water manifold will be along side the still 3/4 copper on the inside and 1 1/2 on the out side so theres plenty of heat transfer there and before it goes back in to the still
i was thinking after seeing what was posted that reflux probably wouldn't work but if i went with more of pot still idea and draw it off right as its going back into the still at the top it would be able to keep the wash in the inside of the manifold at 170 degree

what made me think about this all is my hot water heater for my house is above 170 degrees all the time at the top of it

if i need a little more heat at the house i could bump outside stove to 196 and then the house would go to around 190
i was thinking sense i have a unlimited supply of 180 degree water right now there has to be a way to use it i would just need to heat it up to drop it back down
i have been running a 3 gallon pot still for the last 9 years its getting beat up pretty good so i want to build a new one and bigger and if i could use my outside wood stove for most the heating it would be great
i added a ruff draft of what i had in mind

thanks for all the input so far people

[loneswinger]

1. You could use the hot water to preheat the still charge while filling by using a counter flow heat exchanger.

2. You could use it to preheat the water for an external steam rig that then powers your still.

3. You could use it as preheated water in a continuous forced steam rig that powers your still (this would be a fun build).

I don't think that you could use the hot water itself to power the still, it just isn't hot enough. Unless you are running a vacuum still. Even then it would require a lot of hot water to keep the rig going.

[myles]

3. You could use it as preheated water in a continuous forced steam rig that powers your still (this would be a fun build).

Unless you build pressurised steam boilers / cookers for your day job this is a REALLY bad idea IMO. Glycol will get you to simmilar temperatures at atmospheric pressure.

[loneswinger]

3. You could use it as preheated water in a continuous forced steam rig that powers your still (this would be a fun build).

Unless you build pressurised steam boilers / cookers for your day job this is a REALLY bad idea IMO. Glycol will get you to simmilar temperatures at atmospheric pressure.

With what I had in mind the pressure would be limited by the input line pressure ~ 60 psi or so...ok maybe 60 psi steam is a bad idea.

I do not understand the Glycol idea.

[freebear]

i guess im not understanding why i cant heat it up to a boil and then run it off of the 180 to 190 temp with the wash heating throw the inside pipe and the outside pipe with the hot water heat when i ran my pot still i was ably to get 180 proof on the first run when i keep ed the pot between 170 and 175 temp
the more heat the more impieties that can get into your finished run or the column has to filter out

the best i can see is to put it together and see if it does what expect it to do

[loneswinger]

I guess I am not totally clear on the design, but if you are keeping the wash at 170-175 F, it will not be boiling unless:

1. You are at real high altitude.

2. You are running a vacuum still

3. You have a very high purity wash to start with.

If you could inject the water at say 190 you might be able to pull it off. However, lets say your wash temp is 185 F, and you are heating it with 190 F water. And you want to maintain an energy input of 1000 Watts. That is going to require about 310 L/hr of the hot water (ideally). When the wash gets to 187 F it will require 520 liters/hour of hot water. It just doesn't seem practical, unless like I said, I just don't understand your design.

-Loneswinger

[kiwistiller]

freebear, I think you might be confused between head temperature and pot (boiler) temperature. They are quite different. because the wash is lower in %abv, it will boil at around 200F,and even higher as it depletes itself of lighter fractions such as ethanol. Even though the boiling point of ethanol is lower, this doesn't matter because the BP of the wash is determined by the mixture of fluids, not each specific component.

[myles]

95.6% ethanol boils at temperature low of 78.2 degC. 100% ethanol boils at 78.5 degC.
As ethanol concentration decreases boiling point rises.

[freebear]

ok the main thing is to say it wouldn't be for the wash i have a striper still that i get out at high % but i want to make this one to bump it up after the fast running one it will be voltage controlled electric element then go into the column and im thinking to at controling the heat of the column the bottem part will be 180 to 186 and the top part ill have a mixer valve to drop it down at the top to be 170 to 176 im looking to make this s it comes out pure

[rad14701]

Welcome, freebear...

It sounds like you need to do some serious research because your understanding of distillation, or lack thereof, is obvious... While we understand your eagerness, doing proper research is a requirement around here... To be honest, you are wasting everyones time by attempting to to justify flawed logic... Not trying to be harsh, just forthright...

This "Welcome Center" topic drifted off topic from the very first post and should be moved into the Novice Distillers forum...