## Cylinders

Cylinders have more surface area per unit of volume than spheres. For convenience, (and because it's a common ratio in commercial packing materials), we'll assume that our cylinders are twice as long as they're wide, so if the diameter is d then the length is 2d. Also, to make the argument easier to follow, we'll make each cylinder out of one of the marbles. Doing the calculations, the width of each cylinder is 1 31 3 times the diameter of the marble, or d D 31 3 0.69336D. More math shows that...

## F 1 Yo

This equation shows that when the concentration of the volatile component in the boiler is very low, producing vapor with a very small Yo, F needs to be very close to 1 in order to achieve our aim (which means that you'd get hardly any product D). The higher the concentration in the boiler, the smaller F can be, meaning you need less reflux. This is the reason you need reflux in a column in order to get a pure product. A reflux column on its own will provide some of the total reflux required,...

## Activation

Activation is the process of processing a material that is intrinsically adsorbent, materials such as zeolite or carbon, to enhance its adsorbent properties. Heat and steam treatment activates carbon by helping to create large numbers of small pores of a selected size, and chemical treatments create the proper electrostatic environment to attract and hold onto specific molecules. The most effective activated carbons receive both steam and chemical treatment, and the millions of pores together...

## Support

Clamps hold pieces together, but how do you support the whole device A boiler, a tall column, a still head and one or two condensers makes a top-heavy assembly, just asking to fall over. It should be supported at the top, or in the middle. The simplest way is with a bracket attached to a wall, but another method offers additional benefits. Fasten one end of a wooden plank to a wall with a hinge, and fasten a drop-down leg to the other end. Cut a slot for the column partway through the middle of...

Why all this attention to measuring by mols The reason's really quite simple. A mol of water, weighing 18.016 grams contains the same number of molecules as one mol of ethanol, weighing 46.068 grams. Knowing the relative number of molecules greatly simplifies the calculations for chemical and physical phenomena. The actual number of molecules in a mol is named after the scientist who first proposed the concept, Lorenzo Romano Amedeo Carlo Avogadro, conte di Quarequa e di Cerreto (1776 - 1856)....

## Basic techniques

Here are some useful basic techniques and some tips and tricks that can save quite a bit of time. Remember, it's not our intention to put you through a long apprenticeship before you can begin enjoying yourself. You don't have to be a cabinet maker to enjoy whittling a stick A distillation rig is basically a set of containers and pipes joined together, so most of the techniques that follow will deal with how to assemble these components. This is only a start, because every new project will...

## They were wrong

A compound column is inherently stable in respect of the temperature of the reflux returned by the head condenser, so no special precautions need be taken to control the flow of coolant in that condenser, other than keeping it steady at a rate that ensures complete condensation of all vapor reaching it. Many people have spent needless hours worrying and struggling to design systems that avoid cooling the condensate, and all the time they were pursuing the wrong goal. Some time spent up front...

## Essential oils

Whether or not you know it, you encounter essential oils every day of your life, since they are widely used in food, candy, beverages, perfume, soap and cosmetics. Essential oils were well known even in ancient times. The earliest references to them come from India, China, Persia and Egypt, and the Greeks and Romans conducted extensive trade in oils and ointments throughout the known world. They were extremely valuable products, often worth their weight in gold. This is explains why...

## Stage

The product from a compound still is often much purer than commercially produced vodka, and most people are very satisfied with it as it comes from the still. If you want the ultimate in purity, process the product with activated carbon to remove the last hint of any congeners. We especially recommend carbon treatment if you are planning on making perfumes, essences, or delicately flavored liqueurs. It shouldn't be necessary if you want to make strongly flavored beverages or mixed drinks. The...

## Truth Tables

A Truth Table is a means of checking that you have considered the effects of all the possible ways in which switches can be set, and that no dangerous connections will be made. The usual way of denoting that a switch is ON is to use the number 1, and when it is OFF to use the number 0. The Truth Table in Fig. 7-12 describes the outputs you get when the switches of that example circuit (which happens to be the one we talk about later, and show in Fig. 7-14) are set in all possible ways. You can...

## General principles

Before starting any job, it pays to think about what you want to do, and whether you can do it with the tools and materials you have. It would be nice to be able to duplicate any commercially produced beverage at will, but is it realistic Unfortunately, the answer is no, because many factors are involved in creating the specific flavors in a product. However, you can duplicate many, and come close to many more. In this chapter we discuss how to operate the three types of still to produce...

## Properties common to all fermentations

All successful alcohol fermentations share many properties in common, which are discussed here. In the sections on fermentations for specific purposes, we discuss the differences in procedure that produce the special flavors and characteristics of individual beverage types. No matter what kind of product you are making, some things are always the same, and these are All ethanol fermentations require a source of sugar to ferment, and have limits to how concentrated or weak that sugar can be. All...

## Fully variable control

For reasons spelled out in Chapter 4, light dimmers and motor speed controllers must not be used for heating element control. They are not designed for the power load of a heater, and generate a lot of electrical noise. If you want to have fully variable electronic control, then please use the circuit we have provided in Appendix 5, or purchase a compliant control box for a stove or commercial hotplate element. These circuits will not violate the new regulations, and are designed to handle the...

## Operation

That's it Operation is equally simple. Close the gate valve and follow exactly the same procedure as for any other type of compound still (Chapter 5). When the time comes to draw off the heads, open the gate valve slowly until you are collecting distillate at the rate we recommend at this stage, which is about 1 or 2 drops per second. You may notice the only drawback of this system at this point - there is a lag of around 10 seconds after adjusting the valve before you see any change in the...

Many people confuse absorption and adsorption because the words sound similar, but they are very different processes. When a material is absorbed, it is held within a porous material by capillary action. A sponge absorbs water, and releases most of it when squeezed. A piece of chalk or a brick will also absorb water, but clearly demonstrate that absorbed materials aren't always easily removable. Adsorption, on the other hand, is a process involving intermolecular and electrostatic forces. All...

## Sugarbased washes and

Sugarcane is clearly a good source of fermentable sugar. When cane is crushed, the sugar-rich juices are directly fermentable. However, sugarcane juice is not nearly as acidic as fruit juices, so the fermentation is easily contaminated by wild yeast and bacteria, which can have a significant impact on the flavor of the fermented beverage. Distilling fermented sugarcane juice yields aguaardente (strong water), known best as Cachaga. Sugar is made from sugarcane by boiling the juice down and...

## The Circuit

We have designed the circuit around pre-drilled stripboard (Veroboard type)as this requires no skill at making PC boards. If you know how to etch boards, then you may well end up with a neater arrangement. However, please do not fall into the trap of trying to cram everything into as small a space as possible. That is silly and counterproductive, and dangerous when dealing with the power board. In the diagram, we have completely removed the lands between terminals where breaks are indicated as...

## Vapor pressure

Every substance is a collection of atoms and or molecules held together by mutual attraction. The temperature of that substance is a measure of the kinetic energy these molecules have - the faster they move and vibrate, the higher the temperature. Depending on the temperature and the pressure, the molecules may pack together tightly as a solid, may pack loosely as a liquid, or may freely move around as a vapor. These different states of matter are called phases, and the transition from one...

## How alcohol is created

This book is primarily about distillation, the purification and concentration of impure or weak substances. We recognize that the majority of our readers are interested in the purification of ethyl alcohol solutions, and have included this chapter to describe the necessary first steps - the generation of the impure, weak solution to purify We will not go deeply into the chemistry or biochemistry of the processes, nor will we try to give expert-level advice or directions on any of the...

## The Product

Some of the products you get, particularly the hydrosols, will be cloudy or milky liquids. This is due to the fact that some of the products are very fine suspensions of concentrated substances. Some of them will clear on their own, but some cannot clear, by their very nature. Don't worry about it too much, because you will be using tiny quantities, and if you are using them to flavor spirits or scent perfumes, the substances will dissolve immediately when added to ethanol. It's very rare that...

## Two stage fermentations

Where solids (peels, grains, twigs and stems, other ingredients, etc.) or proteins are present in large quantities, a two-stage fermentation can be very useful, and is traditional for wine production. An initial primary fermentation is carried out, usually in an open fermenter. An open fermenter is usually fitted with a lid to keep the precious fluid clean, but since this is not an effective airlock it can be regarded as being open to the atmosphere. After the initial foaming has died down, or...

## Supercooling and Column Stability

Hot vapor rises in a compound still to be condensed and returned to the column as reflux. How cold can this reflux be before operation of the column is upset Most people's initial reaction is to say, Very little cooling can be tolerated - it may upset the equilibrium, and will certainly change the reflux ratio. This response is so common that it is almost unquestioned, and some people have gone to great lengths to design still heads to minimize reflux cooling. What can theory tell us about this

## Michael Nixon

Mike is a Chartered Engineer, a Member of the Institution of Electrical Engineers, and proud to be a Kiwi. His grounding was in physics, chemistry and mathematics, leading to a career as an engineering officer in the Royal Air Force in England. He is now retired and living in Auckland, back home in New Zealand. Like many Kiwi Blokes, his pride and joy is his Shed. A Shed is a place where a Kiwi Bloke spends much of his time alone surrounded by his tools, current and past half finished projects...

## A final word

We have deliberately made the layout of the circuits large. This has been done for two reasons It minimizes the risk of short circuits Many amateur electronics enthusiasts vie with each other to produce the smallest layout they can. This goes back to the Good Old Days of discrete components, before integrated circuits were even dreamed of. To cram a one or two transistor radio into a match box was considered the height of skill, and sometimes the most amazing techniques were used to achieve...

## Expression

With some kinds of plant material, there's no need for solvents or heat at all. You can simply squeeze the flavoring compounds out of the plant material. Citrus peels are the best-known example. Many of the intense flavors and scents we want are contained in the oils that permeate the outer surface (the zest) of citrus fruit. The white pith is bitter, so be careful to separate the thin, outer oil-bearing layer from it. You can do this with an ordinary kitchen grater, but a Stanley Surform...

## The RF choke

The RF choke is the only component you will have to make yourself, but a quick look at the diagram will show that this is very easy. The choke is simply a hollow bead (a torus) of powdered iron, and the power supply wire is wound as many times as you can around its circumference. The alternating power supply voltage has a frequency of between 50 and 60 cycles each second, and small inductance of the choke will have little or no effect at this low frequency. However, EMI harmonics have high...

## The Workshop

You don't have to grow your own grapes make wine, nor do you need to make all of your own equipment to become a practical distiller. However, it is very useful to know how to make things yourself, even if it's just how to connect prefabricated parts together in different ways. In this chapter, we'll cover workshop basics and several small projects that will help you with your equipment. We will cover the basic techniques needed to make equipment out of copper or brass, and techniques that can...

## Basic electricity

There are four key electrical relationships that are often used If heating elements are connected in parallel, so each has the full supply voltage across its terminals, the total power delivered will be the sum of each of the individual elements If they are connected in series, so current first flows through one and then the other, the total power delivered can be calculated from the relationship 1 Ptotal 1 P1 + 1 P2 Voltage, Current and Resistance are related by Ohm's famous Law Voltage...

## Yeast rehydration

Active dry yeast is often not properly re-hydrated. The first few seconds of re-hydration, as the cell walls re-constitute themselves, are critical to the survival of the yeast. Re-hydrating at too low or too high a temperature will cause a large percentage of the added yeast to be sickly or die, resulting in slower than expected fermentation. The same effect is caused by excessively high sugar concentrations at the beginning of the fermentation. This can cause up to 80 of the added yeast to be...

## First thoughts

Let's start by considering a column under 100 reflux, and assume for the moment that the condenser is perfect - any vapor touching it is condensed and its latent heat whisked away, but it doesn't cool the resulting liquid below the dew point. The mass of the reflux being returned to the column will be equal to the mass of the vapor arriving. The temperature of the reflux will be the same as the temperature of the vapor in the top of the column, so this liquid reflux will trickle down through...

## A graphical description for mixtures

A picture is truly worth a thousand words, and a few graphs can help create a clear understanding of what happens when mixtures are heated and condensed. These phenomena are the reason that distillation works, and understanding them is essential to designing any type of effective distillation Let's start with a methanol water mixture with X methanol by volume. We've chosen methanol because its characteristics are similar to ethanol, but they're not complicated by azeotropism. (Methanol is not...

## Strain selection

The biggest contributors to the final flavor of the fermented or distilled product are the strain of yeast selected and how that strain is treated during the fermentation. Different strains of yeast make different congeners in widely different quantities. They also have very different responses to temperature, presence of specific nutrients, oxygen levels, etc. There is a considerable amount of information available about yeast strains and varieties, in books and magazines as well as from the...

## Some basic requirements

What do you need to get started A place to work, something to hold the pieces being worked on, and a few basic tools will allow you to make a surprising number of quite complicated things. Of course, the better the workspace and the tools, the easier many tasks will become. As with all hobbies, it is best to start with the basics and try your hand. If you are having fun and making progress, you will find it far easier to justify each acquisition of more and better tools and equipment. The...

## Measurement

The Golden Rule of the workshop is Measure twice, cut once. It sounds simple, but is profound. Even NASA has suffered from not observing this rule closely enough. Multi-million dollar projects have been lost because plans were misread and a small component was machined to the wrong size. Always allow for error. This is never truer than when drilling holes. Drills tend to wander when they first meet the metal they're supposed to cut through, and once a hole is started in the wrong place, it's...

## Weights And Measures

There are many different systems of weights and measures in use around the world, and it's often difficult to translate from one to another. Fortunately, the metric system is in use almost everywhere on Earth, and the American and Imperial systems are widely familiar. We shall use the SI metric system as our baseline, and provide conversions to the American and Imperial measurements, where it would be useful. The American and Imperial systems share the same weight and distance measurements,...

## Molecular structures

The structures of the simple alcohols follow a simple pattern, which is easy to understand from a few pictures. The formulae for the first three alcohols are depicted pictorially in Fig. 82. Notice that there are two different pictures of propanol, and four for butanol. This is because there are more than one ways to arrange the molecules of some substances, and these different arrangements of atoms are called isomers. The structures shown here are simply two-dimensional representations of...

## Ways of controlling Power

Electrical services differ from country to country. Methods that work well with a 240V system will not work with 120 V. Methods that work where both voltages are available are useless where only one voltage exists. Most North American homes have both 120V and 240V available, although many, especially in areas served by gas, do not have any 240V circuits installed. Most of the rest of the world uses 240V exclusively. We have written three separate sections on stepwise control - one for people...

## Method

This method starts with lower sugar content and less yeast, and relies on growing your own yeast during the fermentation. Since yeast can be expensive, this is the less expensive method, but it requires more work and monitoring than method 1. Start with sugar concentration of 160 - 220 grams per liter of solution. When sugar content drops to about 41 g l (1.016 s.g., 4 Plato), add 20 grams per liter (2-1 2 oz. per US gallon). Continue this cycle until you have used all the sugar planned for the...

## Stage 3

Toward the end of the run, the vapor temperature begins to rise slightly, and tails begin to appear in the product. Your nose is a better detector of tails than the thermometer, though, and toward the end of the run it is best to start collecting into a bottle and check for the presence of tails every ten minutes or so. If there are no tails, add the contents of the jar to the bulk container each time you check. Once tails appear, collect into a separate container until the temperature begins...

## Other ways of connecting pipes and tubes Readymade couplings

Hardware and plumbing stores carry a wide variety of off-the-shelf connectors that can save you the trouble of making flanges. Connectors have been designed with almost every conceivable situation in mind, and most are designed for easy assembly. Many connectors for pipes come ready soldered, and all that is needed is to slip them onto a pipe and apply heat to make a perfect joint. Others will be threaded, so you can screw the fitting onto a matching mate. These ready-made connectors are almost...

## Moles and Mols

Knowing this scale makes relative measurements easy, because 18.0 grams of water has the same number of molecules as 46.1 grams of ethanol. Such quantities, assigning a practical unit of measurement instead of using atomic units is called a mole, and if using grams then 18.0 grams of water would be 1 gram mole, and 18.0 kilograms of water would be 1 kilogram mole. Of course, a kilogram mole of water would have 1000 times as many molecules as a gram mole, and if you used pounds for your...

## Building Control Boxes

The box itself should preferably be made of insulating material, or firmly attached to the bare ground or earth wire. All wiring must be firmly connected and properly insulated. The wall socket is protected by a circuit breaker or fuse, but it can't hurt to provide extra protection by mounting two fast-blow fuses in the control box itself, one in each heater element line and rated for the maximum current to be drawn. (UK residents will have plugs that incorporate 10amp fuses, providing the same...

## Books available from book stores

Wright (1918) Distillation of Alcohol and De-Naturing Leonard Monzert (1889) Practical Distiller Irving Hirsch (1937) Manufacture of Whiskey Brandy & Cordials Leon W. Kania The Alaskan Bootlegger's Bible (Happy Mountain Publications - 2000) Kathleen Howard and Norman Gibat The Lore of Still Building

## Summary

Since d < 1, this is a converging series with limit N N 1 If T 10 then d 10 x 0.601 220.8 0.03, and the series converges very rapidly. If T 50 then d 50 x 0.601 220.8 0.14. The series still converges rapidly, but takes a bit longer to The reflux oscillates around a mean of N. This oscillation is rapidly damped, and therefore inherently stable.

## Equilibrium Curves

You now have enough information to work out what happens when you heat a mix of ethanol and water and send the vapor through a reflux column, by combining Raoult's and Dalton's laws with either the Clausius-Clapeyron or the Antoine equations. The following demonstration uses the Clausius-Clapeyron equation. We know from Raoult that PTOTAL P1 + P2 X1P1* + X2P2* We know from Raoult that PTOTAL P1 + P2 X1P1* + X2P2* And we know from mol fractions that X1 + X2 1 so As Pi XiP* and also (from Dalton)...

## Connecting pipes and tubes

By far the simplest way of connecting pipes or tubing end to end is to use an off-the-shelf threaded coupling, or a plumbing union. Both of these consist of two separate pieces that can be soldered onto the ends of the pipes to be joined, and then they can be tightened together or taken apart easily with a simple wrench. Connectors have been made with almost every conceivable situation in mind, and you can save yourself a lot of work by looking to see if an off-the-shelf item will do what you...

## Equipment required

You need a boiler (with heater element control), a packed fractionating column, and two condensers a reflux condenser for the top of the column, and a small Liebig condenser for collecting product. You also need a way of hooking them all together and managing the vapor flow. This is done by using a vapor control head. You can make the head by placing a 2.5 cm (1) diameter tee between the top of the column and the reflux condenser. This is a standard plumbing part, and should be available at any...

## Definitions

Alcohol extract Herbal materials are soaked in alcohol and then filtered out. The alcohol retains essential oils, resins and other compounds. Extracts are equivalent to essences and tinctures. Absolute A solvent extract of fragrant materials from botanicals, producing an alcohol-soluble liquid or semi-liquid oil. Common solvents include, among others, ethanol and hexane, which are then removed. Attar A traditional term for the steam-distilled essential oil of rose petals. This term is also used...

## Annealing

A torch is not only useful for soldering or brazing, but can also be very useful for annealing metals. Metals don't have a uniform structure - they're crystalline. If you bend a piece of metal back and forth until it fatigues and breaks, and look closely at the broken surfaces, you'll see the metal crystals exposed on the surface. You might need a magnifying glass, but they're there. When heated to a high enough temperature - usually red hot - these crystals tend to grow together and form...

## Boilers Summary

All of these methods of heating are suitable, and each has advantages and disadvantages, so none of them can be declared the winner. Choose your design based upon your own unique situation. You can make a boiler yourself (paying due attention to grounding and electrical safety, or to fire and ventilation if using open flame heating) or you may choose to buy a boiler ready-made. Small electrical water heaters are a good option because they're compact, sturdily made, and are usually well heat...

## Saturated Vapor Pressures

If you raise the pressure or lower the temperature of a gas or vapor, the molecules become more crowded. As they move closer and closer together, the mutual attraction of the molecules eventually will overcome the thermal energy keeping them in a gaseous state, and droplets of liquid will begin to form in the vapor. A vapor that has reached this point is called saturated. A very common example of this process is fog - a suspension of tiny water droplets in air, which is a mixture of gases and...

## Pot Distillation

A pot still is the simplest type of still to make and run, but the purity and strength of the product are lower than achieved with other designs. Almost any size of tubing can be used to carry the vapor to the condenser, because the dimensions are not critical. 50 mm (2 inches) in diameter by 50 cm (20 inches) is a reasonable size. In this size still, the length or insulation of the tubing have a tiny effect on the quality of the product. You can easily experiment with tube length and...

## Now take off product between condenser and buffer at rate r gmsec

Vapor initially reaching condenser is N gm sec Cooled distillate reaching buffer is (N - r) gm sec Rising vapor condensed in buffer is (N - r)d gm sec Reflux ratio R (N + Nd - rd - r) N N - r +N + (N - r)d N Vapor now reaching condenser is N - (Nd - rd) N - Nd + rd Cooled distillate reaching buffer is N - Nd + rd - r Rising vapor condensed in buffer is (N - Nd + rd - r)d Reflux ratio R (N - Nd + rd - r) + (Nd - Nd2 + rd2 - rd) N N - r - Nd2 + rd2 N N - r +N - (N - r)d2 N Vapor now reaching...

## Speeding up

One way of speeding up the operation of an existing still is to increase the boiler power. As long as you do not get into channeling or choking, this will work very well. Many people have reported being able to run a 50mm (2) column at 2 kW, and a 75mm (3) one at 4 kW. We would not recommend trying power levels any higher than these Your condenser(s) must be able to handle the vapor load created at higher power. The standard reflux coil can easily handle 2000 to 3000 Watts, depending upon...

## Stage 2

After two hours have elapsed at 100 reflux, the system is in equilibrium, and the top section filled with the foreshots. You need to collect this product very slowly, (1-2 drops per second), so you will not disturb the equilibrium. You must proceed cautiously at this stage, because there is only a small quantity of the foreshots and it would be easy to disturb the small zone they inhabit in the top of the column. You will begin collecting them at a temperature as low as 60 C (140 F), and as...

## Compression ring

One specialized type of connector is called a compression coupling, and this is particularly useful for small diameter tubing. A small ring of metal with bevelled edges slips over the pipe. This is the compression ring (sometimes called an 'olive'), whose edges are forced inward to grip the tube when the hollow nut and bolt are screwed together. No soldering is needed, and it forms a gas-tight seal. The only drawback is that this is a one-time joint only, and you'll need another compression...

## Congeners fusel alcohols

(Fusel German for rotgut or hooch) The molecules made by mistake tend to be longer chain alcohols, acids and esters, all of which add flavors (usually unpleasant) to the product, and many of which are toxic. These are called congeners, which means with from the birth - they were produced at the same time and by the same processes as the alcohol we desire. The composition of these congeners, collectively known as fusel oils, or more correctly fusel alcohols, varies with the carbohydrate source...

## Beers and Whiskeys

Beers are fermented products made from cereal grains. Grains store starch (a long-chain molecule made by stringing together large numbers of sugar molecules) as an energy supply. Starch is not fermentable but, when it is broken down, many of the resulting sugars are. Allowing the grain to sprout (called malting) creates enzymes that break down the starch into sugars and shorter-chained sugar polymers (dextrins). When this mixture (called a mash while it contains the grains, or a wort if the...

## Boiling

When neither cold nor warm soaking is fully effective, heating the solvent to its boiling point often does the trick. This is particularly so when the flavor and aromatic compounds are tightly bound in a dense matrix of plant material which hinders access by the solvent. Seeds, bark and root material can all fall into this category and extraction using a boiling solvent is often the only practical way of getting a good yield. This process is limited to use with products that are not affected by...

## Compound Distillation

If you're on the quest for the purest product that can be made by distillation, the compound still is your tool. The price of the distinctly higher purity is a slightly more complex operation and longer operating runs. The compound still is simply a fractionating still with a condenser on the top and a means of returning controlled amounts of condensed liquid back to the column as induced reflux. The fractionating still achieves reasonable separation through the naturally occurring reflux in...

## Worry Free Speedup

Once again, we introduce a trade-off, this time between time and money. A safe and worry free way to significantly speed up the process of compound distillation, without stressing the column or reducing the reflux ratio, is to add columns. Using our guidelines of 1 kW of power for a 50mm (2) column, you could run with a 3 kW element continuously at full power if you mounted three 50mm columns to the still, each with their own condenser. A single condenser could be used, but only if you devise a...

## Activated Carbon

Removing unwanted substances from liquids and gasses by filtering them through a solid material is an ancient technique. The process of adsorption was described as early as 1550 BC in an ancient Egyptian papyrus and later by Hippocrates and Pliny the Elder. It was mainly used for medicinal purposes. At the beginning of the 19th century, the ability of bone char to take the color out of liquids was discovered by the sugar industry in England. At the beginning of the 20th century, methods of...

## Azeotropes

An azeotropic mixture is one whose boiling point is lower than that of any other combination of the compounds in the mixture. This is caused by the attraction between the molecules of the mixture, and is not predicted by the ideal gas laws. When an azeotropic mixture vaporizes, the vapor has exactly the same concentrations as the liquid, which is why you cannot form a more concentrated mixture by distilling. On the left, we've attempted to combine two graphs into one to explain the phenomenon....

## PH

Water molecules are constantly splitting apart (dissociating) into a hydrogen ion (H+) and a hydroxyl (OH-) ion, and just as rapidly, these ions recombine to form water. Acidity is produced by hydrogen ions and alkalinity is produced by hydroxyl ions. In pure water, the concentration of hydrogen ions and hydroxyl ions is equal, and the solution is neutral - neither acidic nor alkaline. In pure water, the equilibrium concentration of H+ and OH- is 0.0000001 (10-7) gram moles per liter. Gram...

## Electrical relationships

Voltage current x resistance volts amps x ohms V IR power voltage x current watts volts x amps W VI thus power W VI V2 R I2R Work is the mechanical expression of energy. In scientific terms, it is the exertion of force over a distance. For example, if you raise a 1 kg mass 1 meter, you have done 9.8 Newton-meters, or Joules of work. Work and energy are measured in the same units. Energy is the capacity to do Work, and it may be exist in many different forms. Commonly encountered forms of energy...

## Heater

Fig. 3-1 shows reflux occurring in a laboratory retort, about the simplest still imaginable. Reflux and Product Ratios The Reflux Ratio is the ratio of the vapor returned to the still as reflux to the total amount of vapor produced. The reflux ratio is often expressed as a percentage if the boiler produces 100 parts of vapor and 90 parts of this are condensed and returned, then the reflux ratio is 90 . Operating under 100 reflux, or at a reflux ratio of 100 , means that all the vapor is...

## Atoms and Molecules

You don't have to be a rocket scientist to understand how distillation works, but it does help to know a little about chemistry - the science of atoms and molecules. Everything is made up of atoms, and those atoms are joined together into millions of different kinds of molecules. Molecules are combinations of atoms, and each different combination forms a unique substance. If a molecule contains more than one type of atom, it is called a compound. We only have to concern ourselves with the...

## Soldering

Soldering is the normal method for connecting copper plumbing pipes. This is a very different thing than the sort of soldering done on electronic circuits with small soldering irons. Heavy duty soldering of large metal parts requires flame, and sometimes a lot of it. You will need those safety goggles Hot solder and corrosive fluxes can spatter alarming distances. Since you will be handling hot metal, a pair of good quality leather workshop or welding gloves is a very good idea. Metal stays...

## Fig

You can see that all the alcohols follow a very simple progression dependent on the number of carbon atoms in their structure. Isomers of a compound have the same chemical properties, but their physical properties such as boiling point are affected by the different way they're physically put together. Have you noticed how much smaller the water molecule is than the others, and the way that the hydrogen atoms are naturally arranged at an angle to the oxygen atom That will prove important later...

Meads are fermented from honey, The most concentrated natural source of sugar. Honey is a mixture of natural sugars, and does not ferment by itself because the concentration literally pulls water out of bacterial or yeast cells (a process called dessication), preventing them from growing. This tendency of concentrated sugar solutions to pull water out of other things is called osmotic potential, and can have a profound impact on the survival and fermentation rate of yeast. The basic mead...

## Preparation for use

The salts and chemical residues that may be present in activated carbon can spoil the flavor of a beverage treated with them. Always wash new carbon thoroughly before using it. The only effective way of washing activated carbon is to boil it for at least 5 minutes in fresh water, then rinse it in several changes of water, then repeat the boiling and rinsing two more times. This treatment will assure that you have pure activated carbon that will not leave any tastes or residues in your ethanol.

## Components

2 x BTA140-600 triacs (115 120V application) 2 x BT130-600 triacs (240V application) 2 x M0C3041 optoisolator zero crossing triac triggers 1 x 74HC00N CMOS 4x2input NAND gate 2 x 100 microfarad 63VDC electrolytic vapacitors (radial.end connectors) 2 x 4.7 nanofarad (0.0047 microfarad) high voltage disc ceramic capacitors 4 x 330 ohm 1 4 watt carbon resistors 2 x 180 ohm 1 4 watt carbon resistors 2 x 5.6 kilohm 1 4 watt carbon resistors 1 x 50 kilohm single gang linear potentiometer 1 x matching...

## Constant Load Heater Controller

This appendix is written for those who already have practical experience in electronics, so we don't spend time explaining what all the components are and how they work. If you don't have such experience, then this appendix may perhaps stimulate interest in yet another useful and absorbing hobby. Only one small part of the circuit discussed here has any direct connection with power supply voltages, so if you get a friend who does have experience in electrical circuits to first check what you...

## Stage 1

It is extremely important to give the column enough time to equilibrate. When this state is achieved, the composition of this mixture remains the same in each zone of the column, even though molecules are entering and leaving that point constantly. In particular, the liquid vapor mix at the very top of the column will eventually consist of one, and only one compound. However, this will only be true when all the vapor reaching the top is returned to the column as liquid reflux. As soon as some...

## Methods of Extraction

We mentioned vanilla as an example of extraction by soaking in a cold solvent, but this is not always the best way of extracting the flavored and scented substances found in the fruits, seeds, leaves, bark or roots of plants. The list of methods below is not exhaustive, but does cover the methods that you can safely use at home. Cold soaking at room temperature in a solvent such as water or ethanol. Hot soaking by subjecting the plant material to a hot liquid solvent. Boiling the plant material...

## Zero crossing and EMI

As switch-on for each heating element occurs when the MOC3041 chip detects rising zero crossing of the main power supply, and switch-off of the power triac naturally occurs when the voltage falls to zero crossing at the end of a half cycle of that supply voltage, sudden voltage ramps are avoided. Sudden voltage ramps occur during every half cycle of the main power supply when triacs are phase controlled, as in small light dimmers, and this is a major source of electromagnetic interference, EMI....

## It is easier to write the pH range is from 2 to

So, the pH of a solution is the negative logarithm of the hydrogen ion concentration, pH -log H+ If the hydrogen ion concentration is increased, the pH drops, and the solution becomes more acidic. If the hydrogen ion concentration is decreased (increasing OH- ) the pH rises, and the solution becomes less acidic in other words, more basic (alkaline). Since the system is based upon powers of 10, a pH of 4 is ten times more acidic than a pH of 5, and a pH of 10 is ten times more basic than a pH of...

## Flanges

Flanges are very useful devices for connecting two items together and are easily made if they're not readily available at your local store. A flange connection is simply a pair of flat plates attached to the two items to be joined together. The plates can be screwed or clamped to each other, with a seal of some sort between them. Flanges are sometimes a better choice than screw-in fittings because they offer great mechanical strength and can be sealed very easily. Flanges may be round or...

## Wood saw

Vernier calipers (extremely useful for measuring tubing - cheap yet accurate digital ones are widely available). Add to this one of those folding Workhorse benches if your space is limited. These are the type which feature a vise top, and are sometimes called mitre benches, with guides for angle cuts. The hand drill is the only power tool you may need at first. If you take on many projects, you will quickly want to move up to a good quality drill press. By the time you get around to lathes,...

## Safety

The control circuit is isolated from all power supply voltages, not only by the optoisolator but also by distance. Connection to the power module is by means of around a couple of metres of 3-core wire. This carries only tiny currents at dry cell battery voltage, so the type of extension lead used with portable tape or CD players is ideal. However, please ensure that the power module is very well insulated and safe to handle with its covers on. Triacs will typically emit around 1 watt of heat...

## Switches

The style and selection of available switches and outlets varies greatly from country to country. The important point in selecting switches for your control box is that they should be able to handle the load. Select commercial or industrial grade switches rated for 20 amperes, and double check that the voltage rating is 240V or higher (most are actually rated at 600v), whether you are making the 120V control box or the 240V version. These are not standard household switches, but should be...

## Reflux

Why have reflux Why is it important After all, we've shown that repeated distillations will produce increasing concentrations of volatile compounds, and you can achieve this in a simple pot still by distilling the product several times. Eventually, you'll end up with a product containing a very high concentration of all the most volatile components of our original brew. The crux of the issue is that little word all. You will end up with all the ethanol, all the propanol, all the butanol, etc,...

## Stepwise control

Boilers can be very effectively controlled if a few carefully-chosen values can be easily selected. One way of doing this, half-wave rectification, is an antiquated technique that definitely violates power regulations. The remaining methods include using multiple heating elements in various combinations, selecting between multiple voltages, or a combination of both techniques. Selecting multiple voltages is only possible in some countries, and having multiple voltages available in a single...

## Scaling Up And Speeding Up

Throughout this book, we have repeatedly offered guidelines for sizing and operating small-scale distilling apparatus. These guidelines (3.75 - 5 cm column diameter, 750-1000 Watts operating power once at temperature) are admittedly conservative, but are known to be safe, reliable and to produce an excellent quality product with minimal attention and intervention. These guidelines are an excellent starting point if you're interested in producing high-quality ethanol for botanical extracts,...

## Templates

We said before that you can save a lot of marking out by drilling holes in one piece, and then using those holes to guide the drill when cutting holes in the other piece. If you have to drill holes like this in a number of pieces, and you want them to all be the same, you can save a lot of time and trouble by carefully drilling small holes in a master, or template, then using that to guide you when drilling all the rest. You will find that you achieve surprisingly good accuracy if the guiding...

## Wines and Brandies

Wines are the fermented juices of fruit, and when wines are distilled the final product is called brandy. Some fruit wines are commonly called by alternate names - for example, cider for fermented apple juice and perry for fermented pears. Most fruit juices will ferment by themselves if left out in the open air (witness an over-ripe plum), but the results are often not pleasant because many different kinds of organisms are present. Many fruits contain considerable quantities of acid (malic acid...

## Mol Fractions

The mol fraction is a very powerful tool when trying to understand what's going on in a mixture of compounds. When you're comparing the effect of the components of a mixture, the most useful way is to consider the proportions of molecules in the mix, which is done by measuring in mols, rather than conventional weights or volumes. The mol fraction of a component of a mixture is the ratio of the number of mols of that component to the total number of mols of all the substances. As an example, the...

## Raoults Law for Liquids boiling of mixtures

Later, Raoult extended this thinking to liquids. Raoult's Law states the vapor pressure contributed by each component of a mixture of liquids is the vapor pressure of that component multiplied by its mol fraction of the mixture. This is because the mol fraction of a component governs the proportion of the liquid surface the component occupies, and the share of the surface occupied by a component controls its ability to escape and make pressure. X1 mols of substance 1 in liquid (mols of...

## The Home Distillers dilemma

Given this fact, you might ask why would anyone want to ferment pure sugar, and the answer is one of the oddities of economics. Due to the nature of distribution channels, purified table sugar is often the least expensive source of fermentable material available to the small-scale experimenter or hobbyist. A home distiller intent upon making pure ethyl alcohol could use any of the above starting materials, but the cheapest, easiest and most available is pure white granulated table sugar. Where...

## Brazing Silver Soldering

Silver soldering and brazing are two techniques similar to soldering, but using materials that melt at a higher temperature and which have a much greater strength. Silver soldering uses solder containing significant amounts of silver. The term brazing comes from the use of brass alloys, but many different kinds of alloys are available for brazing. The temperature at which silver solder melts is much higher than ordinary solder, but lower than brazing alloys. The temperatures used in silver...

## Clausius Clapeyron Equation

We've discussed vapor pressures, and how you can calculate it if you know the number of mols, the volume and the temperature of the vapor. It would be tiresome to have to do this calculation every time you wanted to know what the partial pressure of a substance is at some temperature. The following equation, easily programmed into a spreadsheet, will give a value directly, allowing us to easily determine how a liquid vapor or solid vapor system behaves. The Clausius-Clapeyron Equation is P is...

## Cleaning used carbon

We mentioned earlier that the adsorption process could be reversed with heat. You can use this desorption process to re-activate used carbon. A significant amount of heat is required re-boiling the carbon will not do the job. Industrially, activated carbon is cleaned with steam, or by baking in an oxygen-free oven at temperatures as high as 800 C (1472 F). One of the best ways to re-activate carbon is with steam. You can pack the carbon into a metal tube and blow hot steam through it under...

## Root vegetables and Vodka

Any starchy or sugary root, tuber or stem can be converted into fermentable sugars, and all of them are used for this purpose somewhere on the globe. Reading through old manuals on alcohol production will give you details of many processes based on potatoes, beets, turnips, and just about any other starchy plant you can imagine. The basic process is to convert the starch to sugar using enzymes (from malted grain, fungi, or industrial sources), fermenting the sugars to ethanol, then purifying...

## Scaling up

For small scale distilling, the primary factors that can be easily altered are boiler power and column diameter. Column length will depend on the efficiency of separation, but if the packing is not altered too much then it doesn't make much difference, and 100-120cm (3 to 4 feet) is fine. Change the type of packing, and you're in a whole new ball game. As column diameter increases, the capacity of the column and the area you are trying to distribute reflux over both increase dramatically (by...

## Should I use marbles Ive heard of Raschig rings but what are they and are they suitable for my equipment Ive heard that

This subject is a hotbed of opinions and, quite frankly, a lot of half-baked ideas. We need to go back to first principles to try and shed some light on this contentious subject. Most people just don't understand how a plate in a large column operates. This is made worse by the fact that many of the equations used to describe the process use the term theoretical plate. This leads to the notion that all you need to do is put flat plates in the right places inside a column, and the job will be...

## If only 240V is available

If only 240V power is available, then you can use two elements and use them either independently or both together, either in parallel or in series. A different type of control box is needed, as with 240V it is safe to plug into just one wall socket. The diagram shows two heater elements connected to a control box, which is in turn plugged into the 240V power supply wall socket. There are just three switches a simple ON OFF switch for each of the elements, switches A and B, and a DPDT switch to...

## The Basics

Fermentation requires several things - sugar within certain concentration ranges, healthy live yeast, proper temperatures and nutrients to allow the yeast cells to increase in number and remain healthy throughout the fermentation process. A good, controlled fermentation with complete conversion of the sugars to alcohol but producing no bad or off' flavors, requires a few more Good sanitation and cleanliness Selection of the best yeast variety Using a large quantity of that yeast Fairly precise...

## How to use activated carbon

Activated carbon may be used as a filter bed, passing liquid through it in a slow, steady stream. This is very common industrially, where materials are passed through several beds of activated adsorbents as part of a continuous flow process. However, the longer a liquid is in contact with an adsorbent, the greater the degree of purification. If you are treating alcohol with a filter bed, you should dilute it to approximately 40 before the treatment. This is because the addition of water makes...

## Latent Heat of Vaporization LHV

The Latent Heat of Vaporization is the amount of energy a substance requires to transform from the liquid to the vapor state. If the liquid is being vaporized, this heat is absorbed if it is condensing, the heat is released. The reverse, condensing the same amount of liquid, releases the same amount of energy. This is sometimes called the Latent Heat of Condensation (LHC), but as they are the same amounts, we'll just use LHV to mean both. The following table lists the LHV for several substances...

## Single stage fermentations

Single stage fermentation entirely in glass is possible for beers made from malt extract or separated wort, wines made from purified or filtered fruit juices, honey-mead, molasses, and other sugar-based washes. The general technique is to sanitize the container and airlock, rinse thoroughly with clean water, introduce the fluid to be fermented together with the yeast, aerate, attach an airlock device and wait for initial signs of fermentation to begin - usually 12 to 24 hours. The complete...