Home Distillation of Alcohol (Homemade Alcohol to Drink)
Design Concepts
The following are some of the factors needing to be considered if
building a still.
Heating
Preferably electric - easy
to regulate the power, and no flame source to ignight stray vapours.
Keeping the element within the vessel further reduces the risk, however
it needs to be positioned such that you can easily clean around it.
Internal also means that you always have to keep a minimum amount of
liquid in the still, so that it wont boil dry. On mine this is about
6L - quite a bit if just wanting to do a small experimental run. Some stills
are mounted with two elements - the second is used to speed up the
pre-heating period.
If you are going to use gas, heed the following
advice of David Reid's :
Gas for heating is perfectly safe as long as it dosnt come into contact with
alcohol, ie: the naked flame must not come into contact with alcohol
either in the liquid or vapour form. At a very low % nothing will
happen, in the middle range the alcohol will burn, and at a high % it
will detonate and explode. I use gas (9kg l.p.g. bottle) with my small
glass still that I use for experimenting, and for botanicals.
The requirements you must have or meet are as follows:
1) You must have no leaks.
2) You must have accurate temperature control, or enough xperience to
know what is happening at all times and pretty well what the temperature is.
3) You should remain in attendance at all times and not leave the still
unattended even for a short time.
4) The area it is used in should be well ventillated so there is no risk
of alcohol fumes building up and causing an explosion.
5) Ideally the spirit receiver should be at least 10 to 12' away from
the gas flame so there is no risks of spillage and consequent fire or
explosion.
6) Hoses conveying the alcohol from the condenser to the receiver should
not be able to be burnt, melted, or able to come into contact with the
hot still body or boiler.
Gas is a good medium but you must know what you are doing. Like anything
to do with fire "A good servant but a bad master".
For your first still I would not reccommend it. If you read enough
history books you will see that a lot of early moonshiners did
themselves quite a bit of harm as well as burn down quite a number of
buildings.
Today with good regulators and controls there is no reason why you
should come to harm so if that is what you want to use go ahead but be
sure you know what you are doing before you do.
Having said that I would point out that there have been and there are
from time to time quite a number of fried corpses from people who think
they know what they are doing with electricity but dont.
Good luck with whatever path you choose and dont be afraid to ask
questions.
Have a good talk to your local gas company, B.O.C GAS Co, Air Liquide or
whoever your local l.p.g. supplier is.
Temperature Control
I haven't got this
fancy, rather just run with it at one setting, and ensure that you have enough
cooling water. The amount of alcohol in the wash determines what
temperature it will boil at, not the amount of power supplied. The extra
power will increase the amount of vapour you produce, though, and can
cause problems if the column diameter is too small. Match the power input
to the column size. Some stills have two heating elements - give the extra
boost while heating up to temperature, then just switch back to one, to
keep it simmering while doing the distilling.
Diameter
The more surface area, the easier
for the vapour to come off. So go for wide rather than tall for
the boiling pot.
Boiling Kettle / Pot
These can be made
from a number of readily available items .. old hot water cylinders,
pressure cookers, tea urns, soup pans & large bowls joined mouth-to-mouth, etc.
Just make sure that they will stand stable, are easy to empty without
giving yourself a hernia, and are easy to clean.
Lid
Needs to be sealed well, but not
to cause risk of pressure build up if the condensor blocks. Some
simply push on, and are held there by their own weight. Others are
fastened down with a couple of clips. You may want to consider some
form of pressure relief valve - eg a rubber grommet pushed into place.
Some lids use a length of soft PVC tubing split along its length to fit
around the edge of the lid - this deforms when the lid is fastened,
and helps maintain a good seal. If doing a wash that is prone to
vigorous boiling (eg malt based, or still have unfermented sugars
present), I'll use a couple of "bungy cords" - rubber cords with a
hook each end - to help hold the "pushed on" lid in place. Remember to
open the lid, or a valve in it, immediately after finishing, or else the
cooling vapour will cause a vacuum, which can collapse your still if
air can't get back into the system.
I reckon the only time the shape of the lid would be important is if you're making a
traditional pot still, where you're relying on the shape of the lid to
provide extra surface area for cooling so as to induce a small amount of
internal reflux, and then want to distribute this internal reflux evenly so
as to get it working effectively.
But in a reflux still, where you're generating a far greater amount of
reflux, and from the top of the column, you're counting on it working its
magic over the column packing (to do the equivalent of say 8-10
redistillations), and not via the lid (where you might get less than half an
effective redistillation if it had heaps of surface area ?)
In terms of whether or not putting the column connection off-center
is going to affect the vapour flow up the
column etc, basic hydraulics tells us that the pressure in a container is
equal in all directions - e.g. a car tire will go flat whether the hole is
at the top or at the bottom - so in our case, the steam will head out the
hole in the lid, no matter where we put it.
Condensor
You don't want this to block,
so have it so that it can be regularly cleaned; if using a long length
of tubing (say through a cooling tank), make sure you don't accidentally
crimp it.
Cooling Water
You need plenty of this.
Locate your still close to a tap & drain. Adjust the flow of cooling
water so that the distillate is warm to touch, but not hot nor cold.
If running off a tank or small well, and can't afford the excessive
consumption, try a closed system. Use a small pump to circulate
the water out of a large rubbish bin, through the condensor, and
then draining over a wide, sloping board back into the bin (eg air
cooling as it does so). I had trouble keeping the water cool enough
when the air temperature was in the 30's (C), but it should be
fine in cooler climates. Another solution is to freeze 2L PET softdrink
bottles of water in your freezer, and put these into the water bin
should it all get too hot. Passing the inlet tubing through a bag of
crushed ice also works to cool it.
Water Control
If you want to get real
fancy, you can try to adjust the cooling so that it increases the
reflux ratio at later stages of the run, in order to maintain high
purity output. I don't bother - just check it every half hour or so
by finger to see if it is too hot & the flowrate needs upping.
Packed Reflux Column
As a general rule
of thumb this should be 30-55mm diameter, and 600-1000 mm tall
(14-20 times the diameter).
(see Reflux Still Design Calculations to accurately
work this out for your requirements). If too narrow, the liquid trying to drain back into the still
will be blown out the condensor by the vapour; if too wide it will cool
too much (no vapour get out - all condenses prematurely), or there
will be inadaquate contact between the liquid & vapour and not much
purifying will happen. If in doubt, go slightly too large, then
shove a stainless steel rod or two up through the packing to take
up some of the space. Packing best to use is stainless steel wool / turnings.
Pack as much in as possible, but loose enough that you can still easily
breath through the tube if you try. Position the pre-condensor ABOVE
the packing, so that the liquid it condenses falls back through the packing.
Some designs (eg Partyman's & StillMakers) have the condensor below the packing.
Although these columns will still work, the only purification taking place
is via vapour/liquid that has cooled inside the packing - quite a lesser
amount. The greater the reflux ratio through the packing
(the ratio of falling liquid to rising vapour), the cleaner & stronger
your alcohol will be.
Pot Still Head
Commercial stills sometimes
have the head neck in, then flare out again, before heading off towards
the lyne arm. This is to encourage a little of the vapour to condense
out & return to the still. The more this happens, the cleaner the
liquor will be.
Thermometer
You need to be able to track
the progress of the distillation. For pot stills the thermometer needs
to be mounted in the head, whereas it should be at the top of the packed
column in a reflux still. Either case, its just prior to the condensor.
Cleaning
Make sure everything can be easily
dissassembled for easy & regular cleaning. You may wish to have a tap in the
base of the boiling pot to help drain out the spent wash at the end of a run
(20+ L of boiling liquid is fun to manhandle !).
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