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Water bath pot still


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Has anyone had any experience in using a water bath pot still to produce whiskey? I know this type of still is great for fruits, grappa, etc., but what about whiskey production? Any/all comments appreciated.

I looked at a still that was hiding in Japan a while back. It was a new still and set up for grappa. I spoke with the manufacturer and determined that it could be retro-fitted to basically replace the hot water system with steam...assuming that this is similar, it may be possible to put a steam trap on the return line and run your baby on steam. Low pressure steam will probably get you spirit a lot more quickly than trying to run on hot water.



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A few comments: (I'm addressing this presuming "water bath" means a water jacket at atmospheric pressure)

We have a water jacketed still, but I would not call it a simple water bath. It's a direct fired still, so the water jacket is really just a boiler on the outside of the kettle. When you use a direct-fired still with a water jacket, the jacket is usually allowed to contain a small pressure. This allows the water to rise above 212F, and facilitates heat transfer significantly. The water jacket also provides very nice heat distribution so there's no scorching of the contents as you would find with a true direct-fired still. This type of still is easy to convert to live steam.

Also, we have some experience with using the small glass stills in our lab with a water bath. We were too cheap to buy the really-expensive-joe-cool-guy electric mantles for the still, so we're using butane fueled chafing dish heaters - like a single burner camping stove. When we experienced a bit of scorching around the rim of the puddle of fluid in the bottom of the hot beaker, we tried a water bath. This is simply a bowl of water placed under the hot side. It works okay, but it's a bit slow.

We've not tried this, but the purpose of steam is to get the temperature higher than the contents of the kettle so there's a big gradient between the heat source and what you're heating. If you didn't have steam, only hot water, you might want to try using vacuum to reduce the boiling point of the kettle, and that would hurry things quite a bit.

We have tried vacuum on the small stills mentioned above (but we didn't need the water bath at all)...and our distillations take far less time, the direct fire doesn't cause scorching, and they run cool enough that the turn-around time between runs is significantly lower...we run more times per day using vacuum. Your mileage may vary.

If I had a water bath still and had to run at atmospheric, I would be inclined to fill the bath with something other than water...something that would provide good heat uptake and transfer, and would allow heating above 212F. Perhaps there's an oil or glycol product that would fit the bill. Don't be fooled into believing that because ethanol boils at around 175F, that you'll do just fine using water as a transfer medium because it boils at 212F, so you'll be done when the jacket starts to boil. That's not how it works. A 10% solution of ethanol in water boils at something like 195F, not 175F, so when the water boils, your delta-T is only 7F. That's not going to transfer into the kettle very well.

Good luck,


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