Automated reflux still -newbie needs your opinion

[heksa]

First let me say hello to everybody - what a great place - I am spending way to much time here (that's my wife opinion)
The only other place where you can find so many dedicated maniacs is the ice fishing forum
After tons of reading I am ready (I think) to build my first still. Before any money and/or good material will be wasted
I am asking your opinion.Here is my design:
Automated valve control thanks to member sedso10 (great savings of $ 200.00)
Theoretically controlling temperature over the reflux coil (at + -173F) should send pure alcohol vapors to the
condenser. (probably to good to be true)
Thank you in advance.

[rad14701]

While that design does have some theoretical feasibility, that level of complexity isn't well suited for small runs under 50 - 100 gallons... While this concept works well with continuous still columns, like the Charles 803, it just doesn't perform as well for neutral spirits... The problem lies in the fact that the column head temperature will seek its own level, without the need for a condenser coil at the top... What will end up happening is that the temp will rise, the coolant will increase, and then you'll end up adding more heat, then more coolant will increase, and on and on... You will just end up with excessive reflux while the column chases the thermometer...

When you heat the boiler the vapor that rises will find it's own temperature equilibrium based on percentage of product in the wash... This means that the column will run cool until the low alcohols are removed... The vapor temp will then rise to the ethanol level until it has been removed... The temperature will then continue to rise as you hit the high alcohols... Trying to force the temperature is an act of futility... This is all explained on the main site, http://homedistiller.org" onclick="window.open(this.href);return false;" rel="nofollow, if you need confirmation on this...

Oh yeah, welcome aboard...

[heksa]

I knew it - to good to be true
Thank you - I learned something. Since I am going after clear (neutral) spirits I will stick to VM design

[HookLine]

Yup, you don't choose the vapour temp, it is determined by the mix of components in the vapour.

I have a VM column, they are excellent for neutral spirits.

[manu de hanoi]

The real prob with such design is that it's really hard to pick the narrow zone between high reflux and total reflux. once u reach total reflux then nothing will go out of ur takeoff pipe, I dunno how accurate is the thermocouple but usually you have a 1oC of accuracy on thermo probes (far from enough). What about the valve is it like open or close or do u control aperture size? .

Now if you want to use a thermo probe control it's fine but please put it 50 cm below the take off, a 5 degree variation there equals a 0.1 degree of variation at the takeoff point

[heksa]

Thank you manu , but after reading what rad 14701 said in his post I decided to build VM still
5' (4+1) 2" copper with copper packing and 1/2" gate valve

[manu de hanoi]

Thank you manu , but after reading what rad 14701 said in his post I decided to build VM still
5' (4+1) 2" copper with copper packing and 1/2" gate valve

no automation ?

[heksa]

No , decided to have some fun

[dog1976]

I built a still just like your design, but without PID control and I controlled the refluxing condenser seperate from the product condenser. I have had good luck with this design. You can put it in full reflux, collect one drop per second, 4 drops per second, or collect as fast as a pot still. If I was going to put PID control on it I would put the thermo sensor 1/4 to 1/3 the way down the packing (that where my thermometer is). That way you keep the column in near equallibream. The problem you will have with PID on this design, the atmospheric pressure is different every day and you will have to readjust the temperature to the PID everytime you use it.

[rkr]

Do a search for Automatic Reflux Control (ARC). It has been covered at least in Yahoo's distillers group. Alternatively you could read me old book online at http://distillers.tastylime.net/library ... 20Listings" onclick="window.open(this.href);return false;" rel="nofollow if you want non electric automation.

Cheers, Riku