At some point, after you're legal, you'll likely wonder, can I do this? Yes you can. Although there are many different still designs and variations, the primary principal of the distillation process is still the same; no pun intended. Soooo let's look at a couple of "STILL," examples.
Basically, distillation is the process of purifying liquid A. the stuff you put in the boiler. Boiling it and then condensing its vapor. Meanwhile liquid (B) starts boiling and begins making vapor, but liquid (C) is just sitting there.
Oh! I forget to mention, (A) is (B) and (C). Because (B) and (C) components have different latent heat of vaporization values, boiling and condensation takes place at different times. By maintaining the heat to restrict liquid (C) from boiling, only liquid (B) vaporizes and then condenses.
As you can see, distillation is the separation of one component (chemical) from another in the liquid; in this case (A) liquid is made up of (B) water and (C) alcohol. They separate simply because one boils before the other. In this case, alcohol has a lower boiling point than water, it boils and vaporizes first and begins to rise.
This is possible because of the different heat of vaporization (boiling temperature) between the two. Of course other factors influence the outcome, but this is the fundamental principal. I like to consider ethyl alcohol as liquid solar fuel.
This process that helps explain this is ”PLE” allows the system (still) to provide selective separation of components.
Picture a column with a series of plates (trays) critically spaced up and down the tube. Each plate has a bunch of holes drilled in it.
The holes allow the hot gas to pass through on its way to the top. In such a still column, each tray reaches equilibrium at different times because each one is at different temperature. The tray nearest the heat is the hottest. The most volatile gas rises to the coolest tray on top.
Meanwhile, hot gas pressure forces some of this vapor through a cooling condenser where it’s cooled and condensed into a liquid (alcohol) distillate. Some of it (reflux) is captured and fed back to the coolest top tray where the hot gas lingers.
The cool reflux also chills some of this hot volatile gas, turning it back to a liquid, both of which trickle to the bottom where it vaporizes once again. As for separation, perhaps a certain component is needed that equalizes at a certain tray half way up, there the hot gas can be drawn off condensed and turned into a specific product.
Additional trays may be added to enhance greater component selection. In any case, nearly all of it returns to the bottom – sorta like the suns hydraulic cycle. Anyway, column heights can be anywhere from a few feet for small scale system to the lofty industrial giants. By the way, I'm describing a basic reflux alcohol still.
Actually it's quite simple. Okay, now that you've got a handle on this part, you should have more than enough savvy to begin to how you can design your own still, but read on there's lots more.
Substance
Melting Point C°
Latent Heat of Vaporization kJ/kg
Boiling Point C°
Alcohol
-114
855
73.8
Water
0
2260 (@100°C)
100°
At some point, you'll be making 180 to 190 proof alcohol. Think of it, you’ll be making your own fuel. And you'll learn that a water content greater than 10% isn't fit for fuel. You'll be distilling a high proof clean burning liquid that you can run as is or mixed with gasoline.
Of course, depending on the percentage of ethyl alcohol you intend to run, you may have to modify your vehicle’s fuel delivery system to accommodate the change.
By the way, you should know what the term proof means. For every percentage point of alcohol purity, the proof is doubled; 10% is therefore 20 proof, 50% is 100 proof. What it takes to get to 100% requires correct procedure, precise control and TLC. That’s what this is all about!
Now I'm not going to give you a step by step recipe: i.e., one cup - stir over low heat, bla, bla, bla... There are two many books and web sites and a thousand recipes plus boocoos of information to settle on just one formula, so I'll leave that to you.
Beyond that, I'll provide lists of systems, types, variations, materials, and stuff like that. Then you’ll have more of an idea while getting up to speed. If you’re having trouble with definitions, go here, orrrr try this one.
I recommend that you read everything you can get your hands on – everything. Okay, before you begin to make moonshine, assuming you're legal, you'll need to build or buy a still and a safe place to operate it.
Wash The term wash referred to is simply the liquid extracted from fermented boiled mash. Also called sour mash, wort beer.
Therefore the excess water must be removed by absorption. The excess, also contains small quantities of constituents that influence the product's flavor.
However this is not about distilling alcohol beverages, but fuel. Nevertheless, even such small quantities of water and the impurities it contains can affect the combustion properties of the product.
But columns can be fed in many different ways. For instance a simple pot-tank-feed may be between the rectifier and the boiler. It feeds the column bottoms directly with vapors cooked off the mash, or the wash from a fermentation stripping sections of a column.
The boiler may be located in a separate location even with small systems for convenience. In this case the feed vapor must be kept at a higher temperature than the ambient pressure to work in the column. Good insulation on the feed tubing is called for unless you’re feeding wash from a fermentation tank. You may wish to preheat it first. What ever works. Return to List
Controlling the rate of vaporization for each substance (chemical) in a closed system is the point. Repeated refluxing will achieve increasingly pure alcohol. Mean while equilibrium is accomplished by carefully controlling the heat of the mixture. This way substances can be selectively separated.
In any case, since our focus is fuel for transportation, pure alcohol is our target. It has a higher vapour pressure than water, so it reaches balance with atmospheric pressure before water. This is the point where it boils.
If you’re tracking temperatures with some kind of instrumentation for control purposes, precise boiling points can be tracked and recorded according to yor critical data; i.e., altitude, temperature, time, etc, for future operations. Two examples are shown below
When both temperatures are combined, equilibrium is mid way between waters boiling (212°F) point and alcohols (172.94°F) or (192.2°). This example assumes equal parts of each. One can easily see that changing the ratio will move the mid way temperature in the column.
For instance reducing the alcohol raises the boiling point while more lowers it. Therefore, the mash temperature will fluctuate as more or less alcohol is drawn. One can see how vital a stable cooling system is.
The ordinary pot still can be scaled up or down. The proportions are generally 24:1. That is, if the column is 6 inches in diameter, the height is 144 inches or 12 feet. Of course the larger the pot, the longer it takes to bring it to temperature. Also, the larger the system, the more water needed to cool it.
Also, you may choose to use a refrigerated holding tank for still cooling, or use a storage tank with a return, or the least desirable, tap into a running water supply. The problem with this; you’ll waste a-whole-lot-a-water. See the counter or reverse flow condenser illustration right. A reverse flow is where alcohol vapor is fed into the bottom and forced out the top.
In either case, your still design will govern how you cool the product. For example, a reflux cooling system requires careful monitoring. In other words, condenser reflux circulation in the column must be monitored and well controlled. To little or to much cooling will directly influence the distillates purity and delay distillation time.
Without accurate data, a brand new reflux system will require best guess estimates to get started. Obviously, cut and paste methods require a lot of water to get the best results.
Unfortunately, multiple unknowns prevent plug and play operations. Yet if you get lucky and hit the right combination at the on set, you are the exception.
Nevertheless, if you have data from others proven distillation runs, it’ll take a lot less water and "about six hours to produce about 5 liters of 190 proof from a 25 liter boiler charge," or so says Mother Earth if you use their design. Return to List
With so many different packing materials available, there wasn't enough room to list them all here. Your best bet is to look around at what others have had success with and pattern your design after the proven ones currently in operation.
In reality, the art of designing a still where packing is used is about 50% creativity and 50% science. The creativity part comes from previous hands-on still construction experience. The science you cabn get out-a books.
Therefore, hands-on experience may lead the designer to use economical random packing such as ordinary marbles; yeah, plain ol' marbles. Or if a good source of stainless steel ball bearings is handy, they'll work too.
On the other hand, stainless steel scouring pads loosely piled in the area where the packing is required. Don't use plain steal wool pads because they will rust. And be sure not to cram the pads in so they're compressed. Consider the space between marbles then stack the pads accordingly.
Up scale Raschig Rings can be purchased, all of which can be simply dumped into the small column. Additional surface area is increased many fold, all of which increases the still's productivity.
Pell rings are stamped steel or plastic rings with open perforations around the circumference of the ring. Unlike solid Raschig rings, these provide much more surface area.
On the other hand, structured packing may be carefully inserted, positioning it to avoid pressure drops, but increasing the capacity of the column in large systems.
Structured packing materials are similar to children's building blocks only in different shapes and sizes.
In any case, you'll need something that won't crush, that's easy to clean, won't dissolve, melt, burn, or release impurities into the vapor. Personally I like the marbles and scouring pads.
As for how much is needed, of course that’s determined by the still type, end use, column diameter and height. Like I said, designing a randomly packed column is a mix of creativity and science. For packing material suppliers, see links below.
The pot still is basically a small batch system in the simplest form. It can produce 40 to 60 % alcohol. Though primitive, it collects and condenses boiling mash vapors into alcohol.
It is simply a closed vessel in which the mash is placed, sometimes a simple pressure cooker. As it boils, making steam, the alcohol condenses in a tube and runs into another container. It can be equipped with a column and refluxed if so desired. Return to List
Fuel grade fixin’s aren’t so exact, however quality mash is required. By the way, you may run across or hear the word wort. This is basically the German term for malt or beer. Anyway, a good place to start is the ethyl-alcohol category in the energy recourse's page, There’s a lot of material on mash, warts, and a whole lot a other weird terms, for the fixin's related stuff. Return to List
Sour mash is the most common and most often used method. Basically, a tiny bit of the previously fermented mash, now sour, is saved and used in the next batch to maintain the new yeasts quality.
This sweet mash method is as its name implies. Fresh fermented yeast is used. The purpose is to produce sweeter flavored beverages. Return to List
For example, keeping infectious outbreaks from occurring, careful cleaning between runs is required. Should you experience a still infection, one of the first signs will be a reduction in yield. If Acetobacter gets going, the alcohol you would have produced will be converted to acetic acid - vinegar. Maybe not much, but enough so as to make you wish you had cleaned, or ground that rough surface smooth. Or maybe you enjoy making vinegar.
STUFF YOU SHOULD KNOW Saturation temperature means the boiling point. The phrase saturated liquid means as much thermal energy is contained as it can stand without boiling. On the other hand saturated vapor means the least thermal energy as possible is contained without condensing.
If your design is a column larger than 6 or more inches in diameter, you can have a heating and air conditioning company make the tubing and parts you need at a reasonable price.
If you’re a pack-rat like me, you’ll have many things you can incorporate into a proper system. Look around! Return to List
So, whether it's corn, grain, potatoes, fruit, or what ever you dream up for the mash, when you’ve mixed it up, and put it all together, you’ll be producing ethanol for your car for about a buck ($) a gallon – is it worth it, you bet it is.
After all, with fuel prices on the way up, doesn’t the thought of building your own alcohol still and then using it to produce ethanol for around a dollar a gallon make a lot of sense? You bet it does. Return to List
At some point, after you're legal, you'll likely wonder, can I do this? Yes you can. Although there are many different still designs and variations, the primary principal of the distillation process is still the same; no pun intended. Soooo let's look at a couple of "STILL," examples.
Basically, distillation is the process of purifying liquid A. the stuff you put in the boiler. Boiling it and then condensing its vapor. Meanwhile liquid (B) starts boiling and begins making vapor, but liquid (C) is just sitting there.
Controlling the rate of vaporization for each substance (chemical) in a closed system is the point. Repeated refluxing will achieve increasingly pure alcohol. Mean while equilibrium is accomplished by carefully controlling the heat of the mixture. This way substances can be selectively separated.
When both temperatures are combined, equilibrium is mid way between waters boiling (212°F) point and alcohols (172.94°F) or (192.2°). This example assumes equal parts of each. One can easily see that changing the ratio will move the mid way temperature in the column.
The greater the number of plates, the more zones where various vapors can establish phase equilibrium, thereby allowing the separations of more components.
Another variation of the holed plates above is called a bubble-cap plate. These are used in large industrial continuous distiller systems, although the chemical industry is moving away from this kind to holed plates and packing.
Therefore, hands-on experience may lead the designer to use economical random packing such as ordinary marbles; yeah, plain ol' marbles. Or if a good source of stainless steel ball bearings is handy, they'll work too.
On the other hand, stainless steel scouring pads loosely piled in the area where the packing is required. Don't use plain steal wool pads because they will rust. And be sure not to cram the pads in so they're compressed. Consider the space between marbles then stack the pads accordingly.
Up scale Raschig Rings can be purchased, all of which can be simply dumped into the small column. Additional surface area is increased many fold, all of which increases the still's productivity.
Pell rings are stamped steel or plastic rings with open perforations around the circumference of the ring. Unlike solid Raschig rings, these provide much more surface area.
Stills behave like a series of single pot stills, formed in a long vertical tube. The most important part of any still is its top.
The vapor is introduced into the bottom of the column. Clean water stripped from the alcohol can be used for cooking succeeding batches. In fact this may be the best design for continuous runs. This type is simple to build, and construction costs are low.
As the hot vapor enters the column it is instantly condensed to a liquid by the heat exchanger, however this liquid is immediately vaporized by the hot gases rising from the reboiler.
In fact this one sorta' emulates Hawkeye's creation. It also indicates the reflux feed back and adjusting needle valves.
Adding components can go from as low-tech to hi-tech as you want; e.g. a PC terminal or a dedicated MPU. You could do real-time sampling on pH, temperature, flow rates for feed back to servo controllers, you could even log real time data for future reference and modifications later on. Or you could do everything by hand - its up to you.
Its construction simplicity makes it a popular system. Alcohol vapors rise with a minimum of pressure, stripped water drops through downcomers.
For example the mash must be free of clogs (solids) to avoid fouling the downcomers and caps. The downcomers are the tubing connecting the upper plate to the next plate below. See illustration right.
Basically this system is not recommended for those without a DIY bent. Nevertheless, if you insist, and want to know more about this particular variation, see THE MOTHER EARTH NEWS built collector (Issue No. 56, page 114).
It is generally a blown glass container comprising a bulbous chamber wherein the wash is heated. In order to fill the heating chamber, a hole fitted with a detachable cap is located at its top. The heating chamber has a straight long (tea-pot type snout) tapered neck protruding some distance from the chamber in which hot vapor cools and condensation take place. Since the lone tapered neck is constructed at a downward angle, thus allowing the condensed liquid empty out the end. See illustration right left.
There are usually three parts to the alembic: the main vessel, a large bulbous shaped container wherein the wash is heated, on top of which is the still head, actually a smaller chamber where steam collects The still head also has a long tapered tube that acts as a condenser. This in turn empties into a smaller separate gourd shaped receiver vessel.
STUFF YOU SHOULD KNOW
So, whether it's corn, grain, potatoes, fruit, or what ever you dream up for the mash, when you’ve mixed it up, and put it all together, you’ll be producing ethanol for your car for about a buck ($) a gallon – is it worth it, you bet it is.
