Improvements in Apparatus for Evaporating and Distilling Liquids.
Year: 1895

page_text: Date of Application, 4th Feb., 1895
Complete Specification Left, 30th Oct., 1895-Accepted, 25th Jan., 1896
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Evaporating and Distilling
Liquids.
I ALBERT AUGUSTE ROBIN of No. 21 Boulevard Poissonnière, Paris
Captain of Infantry do hereby declare the nature of this invention to be as
follows:-
This invention relates to the construction and arrangement of a low-pressure
still for the distillation of volatile compounds and more particularly such as are
inflammable.
The still hereafter described may be employed in the preparation of varnish for
plates, photographic films, artificial skins, celluloid plates or sheets and other
analogous materials in which it is desirable to avoid the formation of air bubbles;
it may likewise be applied to the purpose of extracting oils or fatty substances by
means of sulphur, carbon or other dissolving agents, of separating alcohol from
liquids of volatile character, of distilling ether and other volatile products which
are decomposed at a low temperature, and to other analogous processes.
The apparatus consists first of a water-bath or tank for containing liquid,
provided with suitable legs or supports and having an overflow. In the bottom of
the bath a hole is formed around which are arranged concentrically two lengths
of tube, one within the other, having inserted between them mercury, or any non-
volatile liquid indissoluble in the liquid resulting from distillation, or some plastic
substance suitable for forming a seal such as putty, or wax. Upon the surface of
the bath-liquid is poured a sufficient quantity of isolating non-volatile fluid of
lighter specific gravity than the liquid constituting the bath and insoluble therein,
for the purpose of preventing evaporation thereof. Within the bath is arranged
an evaporating-pan supported in a horizontal position by suitable screws provided
around its outer side and resting upon the flange of the bath. The bottom of this
evaporating pan is furnished with a tube bell-mouthed at its upper end joined. to a
length of tube projecting downwardly into the liquid or plastic substance forming
the seal. Below the bottom of the evaporating-pan a short pipe exterior to and
concentric with the downwardly projecting tube extends into the bath-liquid and
also forms a seal. Within the evaporating-par, which is preferably made flat-
bottommed, is introduced the liquid to be distilled or the compound from which it
is desired to eliminate the volatile constituents. The flange of the evaporating-
pan is made in form of a gutter to receive a liquid or plastic substance, similar to
that previously described for forming a seal, and into this the rim of a condenser
is immersed thus constituting a lute-joint. This condenser is of approximately
conical form the bottom being in the form of an inverted cone, and the top raised
towards the centre provided with suitable handles, and pierced with a central
opening for the introduction of hot water or any suitable refrigerating agent. All
parts of the condenser are covered with heat-resisting material, or with an envelope
formed of a non-conductor or bad-conductor of heat, with the exception of the
bottom.
The tube from the evaporating-pan which may be surrounded with cold water
or not, extends downwardly through the bottom of the bath into a receiver or
graduated gauge placed directly underneath and furnished with a suitable stopper.
This receiver is surrounded with ice, or it may be placed in a current of cold
water, and rests upon a disc supported upon a coil or other spring. By depressing

page_text: the receiver upon the spring the pipe or tube from the evaporating-pan may be
disconnected from the receiver when desired to suspend the distillation process.
I may beat the bath either directly by means of gas, or by causing steam to
circulate through a worm arranged around it or through some other suitable
conduit, in such a manner as to maintain a constant temperature. In either of
these cases an automatic beat regulator is fitted in the bath and immersed in the
liquid. If a circulating stream of water, derived for instance from a reservoir of
constant temperature, be employed, the level of the liquid in the bath is kept
always the same by means of the overflow. Evaporation during the distilling
process from the bath is prevented by the non-volatile isolating liquid superposed
upon the bath fluid.
When this latter consists of water petroleum may be
employed for the purpose of preventing moisture and avoiding loss of heat in
the still.
In a modification of the foregoing arrangement the evaporating-pan and the
bath are constructed in one piece, screws being used to support the bath in
position, and a tube passing through the bottom of both vessels forms com-
munication with the tube connected with the receiver below as before described,
but the seal at the junction of the tubes is in this case dispensed with. The seal
around the condenser is however retained.
In operation the solid or liquid compounds placed within the evaporating-pan,
under influence of heat from the bath give off their volatile constituents in
vapour, which being condensed on the bottom of the condenser, the liquid
product gravitates towards the lowest part and runs off finally into the mouth
of the tube arranged directly beneath that point, whence it is conveyed into the
receiver below.
Dated this 4th day of February 1895.
Improvements in Apparatus for Evaporating and Distilling
Liquids.
I ALBERT AUGUSTE ROBIN of No. 21 Boulevard Poissonnière, Paris, Captain
of Infantry, 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 :-
This invention relates to the construction and arrangement of a low-pressure
still for the distillation of volatile compounds and more particularly such as are
inflammable.
The still hereafter described may be employed in the distillation of varnish
for plates, photographic films artificial skins, celluloid plates or sheets and other
analogous materiais in which it is desirable to avoid the formation of air bubbles;
it may likewise be applied to the purpose of extracting oils or fatty sub-
stances by means of carbon disulphide or other dissolving agents, of separating
alcohol from liquids of volatile character of distilling ether and other volatile
products which are decomposed at a low temperature and to other analogous
processes.
In order more clearly to explain my invention reference is had to the accom-
panying drawings upon which
Figure 1 is an elevation of my improved distilling apparatus shewn partly in
section on line x-y of Figure 2;
Figure 2 being a part plan of the apparatus seen from above, and

page_text: Figure 3, a sectional elevation on a reduced scale of an apparatus shewing a
modification of the evaporating pan.
As will be seen
on the drawings my improved apparatus consists first of a
water-bath or tank K for containing a liquid, provided with an overflow D, .
and carried upon suitable legs or supports. In the bottom of the tank K
is formed a hole around which as shewn on Fig. 1 are concentrically arranged
two lengths of tube M one within the other having inserted between them
mercury, or any non-volatile liquid indissoluble in the liquid resulting from dis-
tillation, or some plastic substance suitable for forming a seal, such as putty or
Upon the surface of the bath-liquid B is poured a sufficient quantity of an
isolating non-volatile fluid of lighter specific gravity than the liquid constituting
the bath, and insoluble therein for the purpose of preventing evaporation thereof.
Within the bath is arranged an evaporating-pan R supported in a horizontal
position by suitable screws V. provided around its outer sides and bearing upon
the flange of the tank K. The bottom of the evaporating-pan R is furnished
with a tube O having a bell-mouth at its upper end, and joined to a length of
tube O' projecting downwardly between the tubes M into the mercury or plastic
substance forming the seal.
wax.
Below the bottom of the evaporating pan R a short pipe J¹ exterior to, and
concentric with the tube O', extends into the bath-liquid B, and also forms a seal.
Within the evaporating pan, which is preferably made flat-bottomed, is introduced
the liquid to be distilled, or the compound from which it is desired to eliminate the
volatile constituents. The flange J of the evaporating-pan is made in form of a
gutter to receive a liquid or plastic substance similar to that previously described
for forming a seal, and into this is inserted the rim S of a condenser C, thus
constituting a lute joint. The condenser C is approximately of conical form, the
bottom being in the form of an inverted cone P as shewn on Figure 1, and the
top T raised towards the centre, provided with suitable handles A, and pierced
with a central opening H, for the introduction of cold water or any suitable
refrigerating agent F. The exterior parts of the the condenser C are covered
with heat-resisting material, or with an envelope formed of a non-conductor or bad-
conductor of heat so as to ensure that the heat absorbed by the refrigerating agent
is extracted from the liquid being distilled.
The tube O, which may be surrounded with cold water or not, extends down-
wardly from the evaporating-pan R through the bottom of the tank K, into a
receiver or graduated gauge E placed directly underneath, and furnished with a
suitable stopper. This receiver is surrounded with ice, or it may be placed in
a current of cold water, and rests upon a disc Q, supported upon a coil or
other spring Z, in such a manner that by depressing the receiver E upon the
spring, the pipe or tube O may be withdrawn from the receiver.
I may heat the bath either directly by means of gas, or by causing steam to
circulate through a worm arranged around it or through some suitable conduit, in
such a manner as to maintain a constant temperature. In either of these cases
any automatic heat regulator may be fitted in the tank K and immersed in the
bath-liquid B. If a circulating stream of water, derived-for instance-from a
reservoir of constant temperature, be employed, the level of the liquid in the bath
is kept always the same by means of the overflow D. Evaporation, during the
distilling process, from the bath is prevented by the non-volatile isolating
fluid superposed upon the bath liquid. When this latter consists of water,
petroleum may be employed for the purpose of preventing moisture and loss of
heat in the still.
In the modification shewn on Fig. 3 the evaporating-pan R and tank K are
constructed in one piece, screws V being used to support the whole in position, and
a tube 02 passing through the bottoms of the two vessels forms communication
with the tube connected with the receiver below as before described, but the seal
at the junction of the tubes is in this case dispensed with. The seal around the
condenser in the gutter J is however retained.

page_text: In operation the solid or liquid compounds placed within the evaporating pau R,
under influence of heat from the bath B, give off their volatile constituents in
vapour which being condensed on the bottom'P of the condenser C, the liquid
product gravitates towards the lowest part and runs off into the mouth of the
tube O arranged directly under that part, whence it is finally conveyed into the
receiver E placed below.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. A low-pressure still for distilling volatile or inflammable compounds com-
prising the arrangement of a water bath in a tank K heated, to a constant
temperature by gas or other suitable means; an evaporating pan R containing the
liquid or compounds of volatile substances to be eliminated, a condenser C
containing a refrigerating medium, and a receiver E into which the volatile
substances separated and condensed are delivered through a pipe O from the
.condenser.
2. In a low-pressure still for the distillation of volatile or inflammable
compounds the arrangement of mercurial seals, or seals made of plastic substance
at the junction of the water-bath tank K and the evaporating-pan R, and at the
junction of the evaporating-pan and the condenser C, in combination with an
insulating bed of non-volatile liquid superposed upon the surface of the liquid in
-the water bath as described.