i always wanted to try fermentation and distillation .. so a couple years ago i did ... the result from one gallon of mash was about a liter of very strong alcohol ... note: don't try this at home and i was very careful to make sure there was no methanol
A pot still is a type of still used in distilling spirits such as whisky or brandy. Heat is applied directly to the pot containing the wash (for whisky) or wine (for brandy). This is called a batch distillation (as opposed to a continuous distillation).
At standard atmospheric pressure, alcohol boils at 78 °C (172 °F), while water boils at 100 °C (212 °F). During distillation, the vapour contains more alcohol than the liquid. When the vapours are condensed, the resulting liquid contains a higher concentration of alcohol. In the pot still, the alcohol and water vapour combine with esters and flow from the still through the condensing coil. There they condense into the first distillation liquid, the so-called "low wines". The low wines have a strength of about 25-35% alcohol by volume, and flow into a second still. It is then distilled a second time to produce the colourless spirit, collected at about 70% alcohol by volume. Colour is added through maturation in an oak aging barrel, and develops over time. source: wikipedia
Basically, I made an improvised alembic. The tech is very simple and has been used around the world for thousands of years.
My stove was electric. You are making alcohol - never, ever do this over or near an open flame. The risk of fire or explosion is very high.
There are a huge number of instructional videos on youtube. Most show the same basic layout. I picked one of many for this post. It is probably not the best one so have a look for yourself..
Always remember to toss the first 10% (or so) of your production as it is toxic. Your own numbers may vary. Temperatures are very important, so find a good thermometer and use it.
The images with the enamel pot were taken about four years ago. The setup was used twice and has since gone to recycling. The enamel pot became a momo steamer.
One of the most useful tips I found with my setup was to use homemade bread dough to seal the pot. You can see it as the white ring around the lid. This helped make the process far more efficient by plugging leaks that depressurized the boiler. A pressure cooker may have been more effective, but the setup I used was much safer in that it eliminated the possibility of over pressurization or a clogged relief valve causing an explosion.
Circulating water to cool the vapor coil was an important step. I tried to use just ice but it melts far more quickly than I imagined. Adding the in/out for the cooling water made the whole setup work far better.
Be safe. Have fun.
(some search terms: home distillation, alembic, moonshine, pot still)