Electric fan over boiler lid

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Cakicen
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Electric fan over boiler lid

Post by Cakicen »

I own a simple pot still. I'm thinking of using a fan to disperse the alcohol vapor that may form over the lid and keep it away from the heat below. However, does this cause the steam coming out of the lid to condense immediately and pour back into the boiler (like a reflux)?

Thanks in advance .
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Saltbush Bill
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Re: Electric fan over boiler lid

Post by Saltbush Bill »

If you suspect that alcohol vapor may be leaking from the lid then you need to re access your whole set up and fix the problem properly before running the still.
Cakicen wrote: Thu Dec 08, 2022 2:07 am that may form over the lid and keep it away from the heat below.
I'm presuming that you mean you are running over an naked flame?.......if so a leaky boiler lid is an accident waiting to happen, we don't like or want accidents here, they give the hobby a bad name.
In my opinion the fan will cause some reflux........how much is anyone guess and what its effect on the final product will be wont be known until after the run is completed.
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still_stirrin
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Re: Electric fan over boiler lid

Post by still_stirrin »

Cakicen wrote: Thu Dec 08, 2022 2:07 am I own a simple pot still. I'm thinking of using a fan to disperse the alcohol vapor that may form over the lid and keep it away from the heat below….
As SBB advised, alcohol vapor leaking from the lid is a dangerous situation, even more so if using a burner as your boiler power. Fix all leaks. Flour paste may help with this. Give it a try.
Cakicen wrote: Thu Dec 08, 2022 2:07 am However, does this cause the steam coming out of the lid to condense immediately and pour back into the boiler (like a reflux)?
A fan will create condensation in your potstill riser simply because you’ll be removing heat (energy) from the hot, rising vapors.

However, I wouldn’t call this “reflux” because reflux is the continuous process of condensing and reboiling (and condensing and reboiling) of the vapors such that constituents with a lower boiling point (alcohol, etc.) will separate from constituents with a higher boiling point (water). Reflux occurs when hot rising vapors exchange heat with the cool falling condensate.

Packing in the column provides a surface on which the vapors and condensate can transfer this heat. Without packing in your riser, you’ll simply remove heat which would cause the vapors to change phase (condense). In effect, this would not really boost purity but would definitely reduce the efficiency of your still, meaning you’d be wasting a lot of energy for no (real) benefit.

Bottomline, fix the boiler leaks and adjust your heat input to produce the vapor rate that gives you the correct product stream at the spout.
ss
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Cakicen
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Re: Electric fan over boiler lid

Post by Cakicen »

still_stirrin wrote: Thu Dec 08, 2022 4:58 am
Cakicen wrote: Thu Dec 08, 2022 2:07 am I own a simple pot still. I'm thinking of using a fan to disperse the alcohol vapor that may form over the lid and keep it away from the heat below….
As SBB advised, alcohol vapor leaking from the lid is a dangerous situation, even more so if using a burner as your boiler power. Fix all leaks. Flour paste may help with this. Give it a try.
Cakicen wrote: Thu Dec 08, 2022 2:07 am However, does this cause the steam coming out of the lid to condense immediately and pour back into the boiler (like a reflux)?
A fan will create condensation in your potstill riser simply because you’ll be removing heat (energy) from the hot, rising vapors.

However, I wouldn’t call this “reflux” because reflux is the continuous process of condensing and reboiling (and condensing and reboiling) of the vapors such that constituents with a lower boiling point (alcohol, etc.) will separate from constituents with a higher boiling point (water). Reflux occurs when hot rising vapors exchange heat with the cool falling condensate.

Packing in the column provides a surface on which the vapors and condensate can transfer this heat. Without packing in your riser, you’ll simply remove heat which would cause the vapors to change phase (condense). In effect, this would not really boost purity but would definitely reduce the efficiency of your still, meaning you’d be wasting a lot of energy for no (real) benefit.

Bottomline, fix the boiler leaks and adjust your heat input to produce the vapor rate that gives you the correct product stream at the spout.
ss

Hi still_stirrin, thanks a lot for the informations. Actually there is no leak at the lid. I tested with water vapour and mirror many times. My idea with the fan was just a final precaution, I like thinking paranoid.But now as i understand it is more harm than good.

Cheers
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