Fuel Ethanol still with column
Boiler, can be made of an oil drum for instance ( 200 litres/50 US gallon or smaller) and be heated by fire, steam, with a gas burner or an electric heater.
Alcohol is highly inflammable. If open fire is used as heat source; make sure the still is in a well ventilated area.
With a column strength and quality can easily be improved. This still is easy to operate and provide some reflux over packing to improve strength to at least 60-70 % even if the cooling water flow is unregulated. If the still is run slowly, that is, if the water flow is high the still can deliver higher strength.
Connect the column either to the drum opening or make a new hole onto the lid to connect the column.
Connect a hose from the product outlet on the column to the product vessel and make sure it is in safe distance from the heat source.
The thermometer on the boiler will tell when the distillation is done. When the temperature is 100C or close to 100, it is time to turn the still off.
Detailed instruction about the column:
Material, either copper or stainless steel. The column should be about 3” to provide enough speed to a 200 litre boiler. One metre high is enough to give rather good separation.
A bit from the top, drill a hole through the column and weld/solder a 12 mm pipe in place that goes through the column. This is the cooling tube. It provides the column with some reflux that will help to increase strength. More than one can be used, mount them a few cm apart. Using more will increase strength but reduce speed. Don't use more than four tubes.
At the top, mount a thermometer. If the temperature is close to 78 °C the strength is over 90 %. If the temperature is too high either reduce heat or increase water flow.
The product cooler is made from a 25 mm pipe with an outer shell made from a 40 mm pipe. The sizes is not critical, they are recommendations. Product pipe can be 18-40 mm. Gap between product pipe and outer cooling pipe is best to keep between 3-10 mm. Too large gap and the cooling capability will suffer. As an alternative to a bent pipe and a condenser that goes straight down a condenser at 45 degree angle downward can be welded onto the column.
Packing: It is essential to have some kind of packing into the column. There are several options. Either use 9 mm raschig rings made of ceramics. Or cut 10 mm copper pipe in 10 mm pieces. Or use pot-scrubbers that are made from stainless steel.
Lathe cuttings from stainless steel are a very good packing. This is the preferred choice.
If raschig rings are used it’s necessary to have some kind of packing holder at the bottom of the column. A plate with many holes. Pot-scrubbers and cuttings doesn’t need any plate, it will stay in place by the column wall.
Fill the column with packing from the bottom up to the cooling tube.
Cooling water should be connected from the bottom of the cooler, out at the top and into the cooling tube.
Make sure there is at least 30 cm (1 foot) free space in the boiler when it is filled up with mash.
by Gert Strand AB