Improvements in Processes for Rectifying and Distilling Alcohol and in Apparatus therefor.
Year: 1889

page_text: Date of Application, 15th Mar., 1889
Complete Specification Left, 16th Dec., 1889-Accepted, 18th Jan., 1890
PROVISIONAL SPECIFICATION.
Improvements in Processes for Rectifying and Distilling Alcohol
and in Apparatus therefor.
I EMILE AUGUSTIN BARBET, of Agde, (Herault) France, Manufacturer do hereby
declare the nature of this invention to be as follows
This invention relates to certain processes for rectifying and distilling, and also to
apparatus for the purpose, and has for its object to overcome the difficulties
experienced in the actual processes of driving off the remaining alcohol from the
products of a first distillation.
I have observed that the difference of chemical composition existing between the
liquid which flows back from the condenser into the trays, and the alcohol which flows
to the testing gauge is almost nothing, whence it happens by reason of the great
volume of back flow in comparison with the delivery to the gauge that at the
beginning of a rectification the condenser returns indefinitely into the apparatus an
enormous quantity of volatile products instead of leaving them to separate them-
selves from their contained alcohol.
By my invention I am enabled to increase the yield of the rectifiers and obtain a
greater quantity of product with good flavour and especially to produce much more
pure alcohol.
To this end I collect as better alcohol not those parts which have passed through
the condenser unaffected by its condensing power, but the alcoholic liquid which has
arrived at one of the upper trays or shelves of the rectifier.
This liquid is no other than the back flow itself but purified by the active bubbling
to which it has been subjected during ebullition.
The volatile impurities are easily driven off and the alcohol. which is collected is
purified and refined by the instantaneous ebullition in a much more complete manner
than by the ordinary effects of old age or maturity.
may compare this result to that of heating wines for the purpose of bringing
about the effect of old age, a process invented by M. Pasteur.
My process is applicable to all existing rectifiers of what sort so ever; and also to
the process of continuous rectification, for which Letters Patent No. 9397 of 25th June
1884 were granted, and it is easy to design the means required for the practical
realization of my invention.
The liquid drawn from any tray selected for the purpose is cooled by a serpentine
or tubular refrigerator before it arrives at a special gauge where its delivery is
regulated.
Cocks are placed at the outlets both of the rectifier and of the supplementary
refrigerator so that they may completely cut off in case of necessity, especially at the
beginning and end of the processes of ordinary rectification.
With continuous rectification closing of the cocks is seldom required since the
process of rectification is hardly ever stopped.
To make the new alcohol altogether superior it is necessary to be able to increase the
purity of the last products in the same manner as I have shown for the first products. [
To this end I provide for a second extraction of liquid from one of the trays about
the base of the apparatus, whether the process is continuous or not, but this is of much
less importance than the first extraction aforesaid.
The liquid thus extracted is very impure and contains a great quantity of last
products or "fusel oil."
As in the case of the upper or first extraction a test gauge is also used and a
refrigerator is interposed with suitable cocks; the particular arrangement adopted

page_text: however is of minor importance it being tlie process which is novel and of which
claim the application.
The said process is equally applicable in the distillatory columns especially for such
as produce alcohol of high degree or strength!
:
Thus the residue of distillation or spirits may be rendered much richer in first
products In the case especially of spirits which are not rectified, such for example
as spirits of wine, fruits, cider, tafia in rum &c. &c., an ageing effect can be very
quickly obtained analogous to that which can otherwise only be actually produced
by many years passed in maturing.
1
1000
COMPLETE SPECIFICATION.
Improvements in Processes for Rectifying and Distilling Alcohol
and in Apparatus therefor.
I EMILE. AUGUSTIN BARBET, of Agde, (Herault) France, do hereby declare the
nature of this invention and in what manner the same is to be performed to be,
particularly described and ascertained in and by the following statement :-
A rectifier is generally composed of the following parts—
A boiler furnished with a coil for steam heating.
A column with trays where the refining of the alcohol takes place.
A condenser or an analyser, and finally a refrigerator or cooler after which the
rectified and cooled alcohol arrives at a test gauge and passes ultimately into the
vessels designed to receive it.
The principle of the arrangement of all apparatus for rectification is identical and
based on the same theory.
The operation is as follows:-
The boiler is filled with the residues of distillation or raw alcohol and heated. The
alcoholic vapours which are liberated rise through the tray column where the refining
of the alcohol takes place and they arrive at the condenser which condenses the
greater part of these vapours and returns them in the liquid state to the top of
the trays. It is considered that these are the most aqueous parts and the most
impure of the alcoholic vapours which are condensed and returned to the tray
column, whilst the pure alcohol which has resisted condensation passes to the
refrigerator or cooler and constitutes ultimately the rectified spirit.
This general practice has serious disadvantages principally consisting in the
difficulty of driving off the products of the first distillation.
My new process avoids these defects and is based on observation and on. the
following theory.
It is incorrect that the condenser divides or separates the vapours, on the contrary
between the liquid which flows back (from the condenser into the trays) and the.
alcohol which flows to the gauge, the difference of composition is inappreciable
the volume of the said back flow being four or five times greater than that which
flows to the gauge, whence it follows that the condenser returns continuously into
the apparatus an enormous quantity of volatile products; consequently the stages.
technically called "mauvais goût" or incorrect flavour, "moyen goût" or
Havour, and "demi fin de tête" or half finished first products are so extremely
long as to detrimentally affect the final good flavour desired.
mean
In consequence of these observations I have devised taking the rectified alcohol
from off the trays and not as is at present done from amongst the products' that
have resisted condensation.
In practically applying this process I have proved that the liquid alcohol on the
trays being as I anticipated much more pure in volatile vapours than the back How,
the liquids of the trays correspond at the end of two hours of flow, to a quality
I

page_text: which would not be found at the gauge until the end of eight or ten hours. More-
over in the course of rectification alcohols are obtained absolutely devoid of all
foreign or piquant odour and of a quality much superior to those at the test gauge.
One may say in fact that an "ageing" of the alcohol is automatically produced by
"Pasteurization" analogous to the process of maturing wines.
I will now describe the manner in which I carry my improvement into effect.
I change nothing at the boiler A of the rectifier Figure 1, nor of the tray column B
both of which are or may be constructed on the known or any suitable system
with for example capped or perforated trays: To these sometimes I add a few more
climbers if the existing number of trays appears insufficient. The condenser C must
have a cooling surface sufficient to be able to condense all the vapours which come
from the rectifier: 1 do not touch the refrigerator or cooler nor the pipe d
which conveys to it the uncondensed vapours, but I add a supplementary refri-
gerator G whose function is to cool the purified alcohol which extract from one
of the upper trays of the apparatus. and I regulate the volume of this extraction
by means of a little cock at the entrance to the test gauge F. The outlet cock R
on the apparatus is fully open so that the refrigerator G has its tubular chamber or
its coil charged with alcohol, a condition necessary to obtain a perfect cooling of
the same; then a very small pipe descends from the cock R to a little water vessel H
in which it is rolled up into a spiral and terminates in a little testing cock t. At
the beginning of a rectification the cock R is closed, the bad or impure products of
the first distillation are allowed to escape as usual by a test gauge E, care being
taken to moderate the flow properly so as to keep the trays well filled and con-
centrate therein the volatile vapours; a little while afterwards on the contrary the
flow is allowed to increase, to avoid the condenser offering too great an obstacle
to the départure of the products of the first distillation; then when the alcohol
at the gauge becomes half refined the cock R is opened to permit testing by the
little cock : It can then be ascertained if the alcohol is sufficiently extra fine
for the quality which it is desired to produce, and in this case the cock R on the
refrigerator Ġ, which has remained full of alcohol from the last operation, is
opened. The water of the condenser is replaced by the mere fact that it is in
connection with the water in the refrigerator G and that this water rises to the
condenser. The delivery to the gauge F of extra fine alcohol is regulated and
necessary precautions are taken in order that the combined discharges from E and F
may correspond to the total normal discharge from the rectifier. The flow froin E
can consequently be reduced to a very fine stream which suffices nevertheless to
give issue to the small quantity of the volatile vapours whieh remain in the
apparatus. The alcohol resulting therefrom is besides constantly improving so that
at the end of a certain time it may be put to fine alcohol.
During this time the Pasteurized alcohol from the gauge F attains its maximum
of refinement and neutrality. The testing cock serves further to superintend and
ascertain the end of the operation, but nevertheless it is advisable to impress upon
the distiller the rule that he shall isolate the refrigerator G when the rectification
shall have attained three fourths of its normal duration.
At that time in fact the alcohol at the gauge E also becomes as clear of volatile
vapours as that at the gauge F and there will soon appear a slight smell of the products
of the end distillation. The cocks R and are shut, the water from the refrigerator G
is turned off and from that point the rectification is completed in the usual way.
It will be easily understood that this new process is applicable to all possible types
of rectifiers of which it increases the yield with good flavour ("rendement en bon
goût") and at the same time the purity of the alcohol produced.
This process may be equally applied to my system of continuous rectification
patented under No. 9397 on the 25th day of June 1884 in England. It allows of
obtaining without interruption ordinary fine alcohol at the gauge E; and neutral or
superior alcohol at the gauge.F.
I have only shown up to here one result obtained from my method and that is the
production of alcohol well purified from the products of the first distillation and well

page_text: aged and Pasteurized. The question of the purification of the products of the end
distillation or fusel oils has not yet been considered.
This second purification is very easy to accomplish by means of a second application
of the same principle of extracting the liquids from the trays, only this time it is
from one of the lower trays that I make the extraction, for it is at the lower part of
the tray column that the impurities of the end distillation accumulate. I make there-
fore an outlet for alcoholic liquid from one of the first trays from the bottom, and I
cool this liquid in a little coil L, see figure 2.
The cock K allows the extraction of any volume of liquid desired and when desired,
and this cooled liquid arrives at the gauge M where its strength and odour are proved.
At the beginning of a rectification this product is not very bad and the cock K may
remain shut, but about the middle of the duration of a rectification, it will be found
that the alcoholic liquid becomes extremely bad; it is then necessary to make a
regular extraction in order that these products shall not return into the boiler, and in
order especially that they may not pollute the alcoholic vapours which rise in the tray
column. The extractions are then continued until the end of the rectification.
By virtue of this improvement Pasteurized alcohol collected at the gauge F remains
quite free from all pollution by fusel oil, and as it was already purified of products of
first distillation, it is of a chemical purity altogether superior. 1 will repeat again
that this new principle of extraction is applicable, as in the first case, to all known
systems of rectification whether continuous or not.
When the rectification is continuous, it is from one of the trays at the bottom
(called "plateaux d'épuisement" or drainage trays) that I effect the extraction by
aid of exactly the same arrangement as that already described in reference to the
drawing. There is besides, between the extraction from the top and that from the
bottom, only one difference lying in the quantity of the liquid extracted which is
much less from the bottom than from the top otherwise the analogy is complete.
These processes of extraction of the liquid from the trays have also their rational
application in the distilling columns, chiefly those which give residues of distillation
of high degree or strength.
I append a drawing of the arrangement in Figure 2, although it is practically a
repetition of the arrangement adopted for rectifiers. A is the tray column for
draining the liquid. It receives at the upper part the liquid or mash previously
heated in the heater C. The alcoholic vapours which are liberated from the
column A pass towards the middle of the column B where they are to some extent
rectified.
From the top of B the alcoholic vapours charged with products of the first distilla-
tion pass into the heater C which performs the function of the condenser, the
uncondensed vapours will then go to the refrigerator or cooler 1) and to the gauge E.
From the upper trays extract by the cock R the Pasteurized alcohol which is cooled
by the refrigerator G and descends to the gauge F. By reducing the flow from the
gauge E to a small proportion nearly all of the volatile vapours are concentrated
there, whilst the alcohol passing through the gauge F will be almost absolutely
exempt of same. On the other hand if the extraction from the lower part by the
gauge M is properly done and in sufficient proportion nearly the whole of the oils will
will be extracted thereat. It is again by cock K that the volume of liquid desired
is extracted at the desired time and from whence it passes to the gauge M.
these conditions the alcohol from the gauge F will present with regard as well to the
product of first distillation, as with regard to the fusel oil, a purity such that in
inost cases it will be able to be sold to the consumer direct without any subsequent
rectification.
Under
I thus resolve in a satisfactory manner the problem of direct rectification of
the alcohol contained in the fermented worts by means of a single and unique
apparatus.
The same extractions may be effected whatever may be the nature of the distilled
liquids and especially for the distillation of liquids from fruits of which the spirits are
consumed without rectification, cognacs, dregs, rums, kirchs &c.

page_text: Thus at the first operation by an automatic Pasteurization various natural products
will be aged and matured by removing from them at will the products of the first or
last distillations which are liable to depreciate their value.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is
1. The hereinbefore described process of extracting after cooling the alcoholic
liquid from the trays of the apparatus, whether it be a continuous acting rectifier or
not, or a distilling column, the said extraction taking place for the purification of
products of the first distillation from the upper trays, and for the purification of the
products of the last distillation from the lower trays of the apparatus, these extrac-
tions being based on novel principles and effecting the production of much purer
alcohol.
2. In the application of the process above claimed I claim the apparatus and the
combinations of apparatus hereinabove set forth.
(a) For the purification of the products of the first distillation the supplementary
refrigerator G the cock applied to the gauge F, the pipe going from the
outlet cock and combined with a water vessel H and a testing cock t.
(b) For the purification of the products of the last distillation, the coil refri-
gerator or cooler L, the extracting cock K, the gauge M, these arrange-
ments being also applicable to distilling columns as well as rectifiers in the
manner set forth.
Dated this 14th day of Decemb…… 1000
J. C. CHAPMAN, F.I.P.A.,
70, Chancery Lane, London, W.C., Sub-Agent.