double boiler plan

In our view 30 gallons and under is considered hobby size. Do not bring anything larger than this to our site.

Moderator: Site Moderator

Post Reply
User avatar
Fredistiller
Site Donor
Site Donor
Posts: 253
Joined: Fri Feb 07, 2014 11:48 am
Location: Somewhere in Europe

double boiler plan

Post by Fredistiller »

Hi everyone,

I am planning of making my second potstill. As I run only brandy (later maybee some rhum) I would like to make a double boiler to prevent scorching. After reading almost all the topics in this forum about double boiler, I started drawing my plan.

I tried to make as much contact my with wash as possible. But with less volume possible.
For two reasons:
1. Minimise the weight, I had back surgery 25-30kg is the max for me. :?
2. Try to make "short" response time. (short in term of bouble boiler of course)

The idea is to have a "chamber" in the bottom with the heatings elements in it (2x1500W). I let 10mm space between the elements and the plate.
And a "layer" of 10mm all aroud the boiler at the same level than the wash. Is this enough to have a good circulation?

The volume of the double boiler is 9.5L of propylene glycol or oil.

Every plate would be 1,5 mm SS 304, tig welded. I also plan to insulate it very well with 50 mm Rockwool.

All the re/fill ports-drain needed are NOT drawn! I would do it later if this plan receive a GO from this forum.

I would really appreciate if you can have a look at my design. I know there are some drawings you can find in this forum, and I am not thinking I am smarter than everybody proposing this design. I tried to make the best /less bad design I could for the two reasons above. But if you have comments/questions please shoot!

I put two drawings: one pic in 3D and a sectional one in pdf.

Thanks in advance,

Fred.
Attachments
A view in 3D
A view in 3D
double boiler plan 2.pdf
A sectional drawing
(183.5 KiB) Downloaded 113 times
User avatar
der wo
Master of Distillation
Posts: 3817
Joined: Mon Apr 13, 2015 2:40 am
Location: Rote Flora, Hamburg

Re: double boiler plan

Post by der wo »

Perhaps building an agitator is easier? Cheaper? And will have less weight? And not the heating medium but the mash itself is circulated. If you have a very thick mash, the center will always be colder than the outer layer without agitation. This will smear the cuts, at least when distilling very thick mashes.

In my signature is a link to my agitator build. There are other ways too for sure.
In this way, imperialism brings catastrophe as a mode of existence back from the periphery of capitalist development to its point of departure. - Rosa Luxemburg
User avatar
Fredistiller
Site Donor
Site Donor
Posts: 253
Joined: Fri Feb 07, 2014 11:48 am
Location: Somewhere in Europe

Re: double boiler plan

Post by Fredistiller »

Thanks for the reply Der Wo. I'll keep on searching...
ShineRunner
Swill Maker
Posts: 464
Joined: Tue Dec 08, 2015 11:12 am

Re: double boiler plan

Post by ShineRunner »

There are a few double boiler threads floating around. Look at shadylane's build. I think Jimbo made one too, but not a lot of details on it.

Also, much easier than building a double boiler and achieving somewhat the same result would be building a second boiler/thumper for cooking your wash (I believe it is Marc when making brandy?). You can steam your Marc with a steam generator, boiler, etc, and not have to worry about scorching the solids in the wash. Look at the steam distillation thread. There's a lot of useful information in there about it, including safety precautions that need to be taken.

Plus you'd have the benefit of having a thumper for your eventual rum distillation.

SR
User avatar
Fredistiller
Site Donor
Site Donor
Posts: 253
Joined: Fri Feb 07, 2014 11:48 am
Location: Somewhere in Europe

Re: double boiler plan

Post by Fredistiller »

Yes that was also an option I had in mind. Clear the wash, put the liquid in the boiler, and put the solids in a thumper.

I always had some warm/boiling water on the fruits to kill every undesirable yeast and bacteries. So my washes are never that thick. Thanks for the comment!
User avatar
Danespirit
Site Donor
Site Donor
Posts: 2647
Joined: Tue Dec 25, 2012 8:09 am
Location: Denmark

Re: double boiler plan

Post by Danespirit »

Good replies so far..

If you still want to go the way with a double wall boiler, your solution would work.
I would go with two 2 KW elements for a shorter heat up time....that would be if your power circuit and breaker allows it.
You'll have to compensate for the expanding liquid in the construction. A vent or an overflow vessel would be a solution to that.
When you think of the expansion tank on the cooling system of a car, it only takes a small vessel to let the liquid flow forth and back. :idea:
How about making a stand where the boiler pivots around two axles, one on each side..?
It would allow you to tip and clean the boiler very easy. Furthermore, it eliminates the need for a drain pipe that goes all the way through the glycol chamber to the inner boiler.
The stand doesn't have to be out of expensive stainless steel. A frame made out of mild steel, could do the job , too..
User avatar
Fredistiller
Site Donor
Site Donor
Posts: 253
Joined: Fri Feb 07, 2014 11:48 am
Location: Somewhere in Europe

Re: double boiler plan

Post by Fredistiller »

I think that with a stand, I will splash my kitchen. :D

After some reflexions I think I ll go for the solution of clearing the mash and the thumper. With ULD elements it should be OK.

Thanks for the replies anyway! :thumbup:
Post Reply