Improvements in Apparatus for the Condensation of Vapours for Distilling and like Purposes.
Year: 1898

page_text: Date of Application, 19th Jan.,
1898
Complete Specification Left, 3rd Aug., 1898-Accepted, 22nd Oct., 1898
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for the Condensation of Vapours for
Distilling and like Purposes.
I, CECIL HOWARD CRIBB, of 136, Shaftesbury Avenue, London, W., Analytical
and Consulting Chemist, do hereby declare the nature of this invention to be as
follows;-
-
The object of my invention is an improved form of apparatus for the conden-
sation of vapours for distilling & like purposes.
The condensers hitherto employed as a rule consist of a more or, less elongated
space (generally tubular) in which the condensation takes place with walls of
glass or metal kept cool by contact with air or water or the condensing chamber
may be a narrow space enclosed between two concentric spheres of glass or metal,
through the inner of which water circulates while the outer is only cooled by
contact with the air. A still more recent plan carries this latter arrangement a
step further so that the condensing space is a hollow cylinder (i.e. annular in
section) cooled on both inner and outer surfaces with running water.
My invention so arranges matters that if required the water can be made to
flow over the outer surface in a very thin stream, so that with liquids boiling
above 100° C., the water gets converted into steam, thus taking advantage of the
latent heat of vaporisation to cool the external wall with a minimum water supply.
The condensers may be constructed of glass, china, metal or other suitable
material and may be of various shapes and dimensions. The accompanying
diagrams, Figs. 1 to 3 show in longitudinal section the general form most suitable
for chemical work on a small scale, for which, when made in glass or metal this
type of apparatus is especially adapted.
The condenser consists of an inner tube (A) closed at its lower end and fused
at (X) to a slightly wider outer tube (B), which surrounds (A) and is narrowed
below into the tube (C), from the end of which the condensed liquid escapes.
The cold water supply is conducted to the bottom of (A) which it fills and over-
flows, running down the outside of (B) till it reaches the upper part of (C) where
it is intercepted by the little cup (D), through the escape tube E of which it
flows away to waste. This cup may if required be made so large as to completely
enclose the whole of the body of the condenser and in this case the direction of
flow of the condensing water may be reversed.
The vapour to be condensed may enter the condensing chamber directly
through a side tube J (as in Fig. 1-3) which may be wide enough if necessary
to take the end of a retort, or it may enter indirectly through a tube with an
expanded head, joined to the top of the condenser G Fig. 1. This head may
have two openings as in the figure, of which one is adapted for use with a retort
or a Wurtz distilling flask. The other K may be connected with a vacuum pump
when it is desired to distill under reduced pressure or a special tube may be
SD Q77

page_text: attached to another part of the condenser for this purpose, or the entrance tube may
be joined to the inner tube (A), as in Fig. 1, H so that the joint is completely under
water or both entrance and exit may be below the condensing chamber so that
by the simple turning of a tube the condenser may be used as a reflux condenser,
or for distillation at will, it being only necessary to place the receiver below the
mouth of the exit tube. When used as a reflux condenser the vapour of course
enters through the tube C. When employed for very volatile liquids the retort
or other vessel in which the liquid is heated and the receiver may be attached
by well fitting corks to the condenser, and to the other inlet K Fig. 1, a short
U-tube containing mercury (to act as a safety valve) is affixed, the distillation
or digestion may then be carried on in an entirely closed space, so that any loss
from evaporation is impossible.
To further increase the efficiency of the condenser the condensing space (Q)
between the inner (A) and the outer tube (B) may be converted into a spiral
channel by a spirally wound wire W, Fig. 3, tube or band of metal or other
suitable material, thick enough to prevent any short cut between the adjacent
turns of the spiral channel. It need not come into absolute contact with or be
tightly fixed to either of the walls of the condensing chamber, as the condensing
liquid will of itself be quite sufficient to prevent the vapour from taking other
than the spiral course, by closing up any small space between the spiral tube,
wire or band and the walls of the condenser.
As the fused joint at X is somewhat difficult to make in large glass condensers,
it may be altogether avoided by making the apparatus in two parts, as in Fig. 3,
and joining them by a ground joint or by a stout rubber ring R made if desired
T-shaped in section, or of other suitable form, so as to keep the glass surfaces
from touching one another. In this case the condenser can only be used with
liquids which do not act on or dissolve india-rubber.
Where it is desired to use a minimum quantity of water for cooling the appa-
ratus I employ various devices to spread the water evenly over the outside, and
avoid the necessity of having the top edge of the condenser on an accurately
horizontal plane. Thus string or wire may be wound round the outside in a
not too close spiral or the whole surface may be covered with muslin or with
wire-gauze, or with calico, blotting paper or any suitable absorbent substance,
or, (especially in metal condensers,) the wall of the condenser may be carried
above the joint X, and be perforated with holes a little below the top or the upper
edge may be serrated all round the top, or any combination of these devices
may be used.
The advantages of the condenser are:-
(1) The size is greatly reduced, while the efficiency is increased as compared
with the ordinary (straight) or the worm condenser.
(2) No special form of clamp is necessary to hold it. A vertical hole in a
block sliding up and down a retort stand being sufficient, as the condenser always
works in one position, i.e. vertical.
(3) The condenser is very easily adapted for working under reduced pressures,
or distilling, etc. in a closed space.
(4) For extremely volatile liquid in work in hot climates, the cup i.c. the inner
tube A, may be filled with ice or any freezing mixture. In any case the expen-
diture of water may be largely reduced.
(5) In the case of metal condensers made as in Fig. 3 & of glass ones made
as in Fig. 2 the inside of the apparatus is very easily got at for cleaning purposes.
Dated this 17th day of January 1898.

page_text: Improvements in Apparatus for the Condensation of Vapours for
Distilling and like Purposes.
I, CECIL HOWARD CRIBB, Analytical and Consulting Chemist, of 136, Shaftesbury
Avenue, London, W., do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement; -
The condenser is constructed in the manner hereafter described. The letters
refer to the drawings sent in with the Provisional Specification No. 1496
January 19, 1898.
The condenser consists of an inner tube A closed at its lower end and fused
at X to a slightly wider outer tube B, which surrounds A and is narrowed below
into the tube C, from the end of which the condensed liquid escapes. The cold
water supply is conducted to the bottom of A, which it fills and overflows, running
down the outside of B till it reaches the upper part of C, where it is intercepted
by the little cup D, through the escape tube E of which it flows away to waste.
This cup may if required be made so large as to completely enclose the whole of the
body of the condenser, and in this case the direction of flow of the condensing
water may be reversed.
The vapour to be condensed may enter the condensing chamber directly through
a side tube J (as in Fig. 1-3) which may be wide enough if necessary to take
the end of a retort, or it may enter indirectly through a tube with an expanded
head, joined to the top of the condenser G Fig. 1. This head may have two
openings as in the figure of which one is adapted for use with a retort or a Wurtz
distilling flask. The other, K, may be connected with a vacuum pump when it
is desired to distill under reduced pressure or a special tube may be attached
to another part of the condenser for this purpose, or the entrance tube may be
joined to the inner tube as in Fig. 1, H so that the joint is completely under
water. When employed for very volatile liquids the retort, or other vessel in
which the liquid is heated, may be attached by well fitting corks to the condenser
and to the other inlet K, Fig. 1, a short U shaped tube containing mercury (to
act as a safety valve) is affixed, the operation may then be carried on in an
entirely closed space so that any loss from evaporation is impossible, while at
the same time air can enter or leave the condensing space by displacing the mercury
into one or other limb of the U-tube and then bubbling out or in through it.
To further increase the efficiency of the condenser the condensing space Q,
between the inner (A) and the outer tube (B) may be converted into a spiral
channel by a spirally wound wire, as in Fig. 3, (W) which represents in section
a metal condenser tube or band of metal or other suitable material, thick enough
to prevent any short cuts between the adjacent turns of the spiral channel. It
need not come into absolute contact with or be tightly fixed to either of the walls
of the condensing chamber, as the condensing liquid will of itself be quite suffi-
cient to prevent the vapour from taking other than the spiral course by closing
up any small space between the spiral tube, wire or band and the walls of the
condenser.
As the fused joint at X is somewhat difficult to make in large glass condensers,
it may be altogether avoided by making the apparatus in two parts, as in Fig. 2
and joining them by a stout rubber ring made if desired T shaped in section,
or of other suitable form, so as to keep the glass surfaces from touching one
another. In this case the condenser can only be used with liquids which do not

page_text: act on or dissolve india rubber. This mode of construction has the additional
advantage of being easily taken to pieces for cleaning. In place of the india
rubber joint, metal condensers may have a screwed joint as in Fig. 3, X or a
slip in joint, or the junction may be effected in large condensers by overlapping
flanges kept together by nuts and bolts.
Where it is desired to use a minimum quantity of water for cooling the appa-
ratus I employ various devices to spread the water evenly over the outside, and
avoid the necessity of having the top edges of the condenser on an accurately
horizontal plane. Thus string or wire may be wound round the outside in a
not too close spiral, the whole surface may be covered with muslin or wire gauze,
or with calico, blotting paper or any suitable absorbent substance or, especially
in metal condensers, the wall of the condenser may be carried above the joint ✗
and be perforated with holes a little below the top or the upper edge may be
serrated all round the top, or any combination of these devices may be used.
To prevent the water in the inner tube A being spilt by any sudden movement
of the condenser, the cold water supply tube may be made to pass through a
cork which fits into the top of A and has on its outer surface a number of vertical
or spirally cut slits, through which the water may leave A on its run to the outside
of B, or especially in the case of metal condensers, instead of cork, a metal disc
may be fitted on to the cold water supply pipe, having its outer edge bent down
so that when in position a passage about 2 in. wide is left between the hori-
zontal part of the dise and the top and between the downturned edge and the
sides of the condenser respectively, the water is then directed vertically down-
wards, so that if the supply tap is suddenly turned on, it is bound to follow its
proper course.
To prevent accidents the escape tube E should be made about twice as wide
as the cold water supply tube.
16
To ensure the greatest efficiency the condensing space Q should be as narrow
as possible, consistent with a low resistance. Thus, a metal condenser, of which the
body measured 4 x 5 in. is made with the tube A and B so near together that
it only holds 9 cubic centimetres of water, when condensing at the rate of
4000 cubic centimetres an hour, the resistance was equal to about one inch of
mercury.
Having now particularly described and declared the nature of my invention and
in what manner the same is to be performed, I declare that what I claim is;-
(1) The general form of condenser herein before described.
(2) A double surface condenser as herein described having both surfaces cooled
by running water, the outer being cooled by water running over it in a thin
stream so as to admit of free evaporation.
(3) Glass and metal condensers as herein described so constructed that they
can be taken to pieces, the whole interior being easily accessible for cleaning
purposes.
(4) The employment of the spiral band or wire running round the condensing
space and thus converting it into a flat spiral passage.
Dated this 3rd day of August 1898.
CECIL H. CRIBB,
Applicant.