Improvements in Condensing and Cooling Apparatus for Acid Vapours.
Year: 1895

page_text: Date of Application, 26th June, 1895-
Complete Specification Left, 26th Mar., 1896 Accepted; 2nd May, 1896
PROVISIONAL SPECIFICATION.
Improvements in Condensing and Cooling Apparatus for Acid
Vapours.
I, EDWARD HART of Easton in the State of Pennsylvania, United States of
America, Professor of Chemistry; do hereby declare the nature of this invention
to be as follows:-
The present invention has reference to that class of condensing apparatus
wherein the condensing chamber is composed of glass or similar fragile material.
which is extremely liable to breakage when the apparatus is in operation:
In the Specification of a Patent granted to Henry Edward Newton, on my
behalf, dated September 11th 1894, No. 17289, I have described an apparatus of
this class, the condensing chamber of which consists of a number of glass. tubes
placed parallel one above the other. The heated vapours pass through these
tubes, which are maintained externally cool by the evaporation of water.
delivered from a pipe against the topmost tube, and trickling downward over
the others.
The danger of fracture in such an apparatus is increased by. too great. a
difference of temperature between the cooling liquid. and the hot, gas, by any
irregularity in the distribution of the cooling liquid, and by.currents of cold air:
striking the glass condenser on the outside. As a safeguard against this danger
of fracture, I now cover the tubes with thin open cloth, made of cotton, nitro-
cellulose, or other porous material. This covering serves to distribute the water.
evenly over the whole surface, to reduce the danger of fracture by interposing
continuously a poorly conducting liquid film between the hot glass and the colder
outside air, and, moreover, protects the condensing surfaces from mechanical
violence.
When the temperature of the outside air becomes low, it is possible and desirable.
to raise the temperature of the cooling water by passing the pipe by which it flows.
to the condenser through a fire, or by other suitable means. In this way, it is evident
that the difference between the temperature of the hot gases within the tube.and.
the cooling liquid outside may be regulated as required, and the danger, of fracture..
may be correspondingly decreased!
Although bave described my present invention, in connection with the
apparatus described in the Specification of the Patent above named, it will be.
understood that the improvement is applicable also to similar apparatus of somewhat
different form.
Dated thie Oschide ofJune 1805 ...
COMPLETE SPECIFICATION...
Improvements in Condensing and Cooling Apparatus for Acid
Vapours.
.1
1 EDWARD HART of Easton in the State of Pennsylvania, United States of
America, Professor of Chemistry, 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:
-
The present invention has reference to that class of condensing apparatus -

page_text: wherein the condensing chamber is composed of glass or similar fragile material,
which is extremely liable to breakage when the apparatus is in operation.
In the Specification of a Patent granted to Henry Edward Newton on my behalf
dated 11th September 1894, No. 17289, I have described an apparatus of this class,
the condensing chamber of which consists of a number of glass tubes placed
parallel one above the other. The heated vapors pass through these tubes, which
are maintained externally cool by the evaporation of water delivered from a pipe
against the topmost tube, and trickling downwards over the others.
The danger of fracture in such an apparatus is increased by too great a
difference of temperature between the cooling liquid and the hot gas, by any
irregularity in the distribution of the cooling liquid, and by currents of cold air
striking the glass condenser on the outside. As a safeguard against this danger.
of fracture, I now cover the tubes with thin open cloth made of cotton, nitro-
cellulose, or other porous material. This covering serves to distribute the water
evenly over the whole surface, to reduce the danger of fracture, by interposing
continuously a poorly conducting liquid film between the hot glass and the colder
outside air, and morcover protects the condensing surfaces from mechanical
violence.
When the temperature of the outside air becomes low, it is possible and desirable
to raise the temperature of the cooling water by passing the pipe by which it flows
to the condenser, through a fire, or by other suitable means. In this way it is evident
that the difference between the temperature of the hot gases within the tube and
the cooling liquid outside, may be regulated as required, and the danger of fracture
may be correspondingly decreased.
For the purpose of illustration, the invention is shown in the accompanying
drawings as applied in connection with an apparatus for condensing nitric acid
similar in general construction to that shown in the Patent above referred to, and
this construction will now be described, and the features forming the invention then
be specifically pointed out in the claims.
In the drawings,
Fig. 1 is a diagrammatic side elevation of the apparatus.
Fig. 2 is a cross section of one of the copdenser tubes, ou an enlarged scale.
From the retort A, the vapor passes through the pipe B into the vessel C, with
the top of which connects a vertical pipe D, which communicates, by a series of
condenser tubes E, with a second vertical pipe F, which is open at the top, so as to
form an escape pipe for non-condensable gases. The tubes E are shown as inclined
backward, so that the acid will flow back, through the tubes E and pipe D, into the
vessel C, from which it is syphoned off, by the syphon H, into the bottle or other
receiver I. The tubes E, however, are approximately horizontal, so as to expose
the tubes throughout their length to the action of the sprinkler placed above them,
which is shown as formed by a perforated liquid supply pipe G, any liquid not
evaporated being caught by trough K, having drain pipe k. The vessel C and
vertical pipes D, F, are preferably made of stone-ware, glass, or other similar
material, suitable to resist the attack of the acid, and 'the condensing tubes E are
preferably made of glass or similar material suitable to resist the attack of the
acid, and at the same time conduct the heat from the gases quickly, so as to secure
the proper cooling action. The size of these tubes E may be varied, but a construction
which is found efficient in practice, is produced by using tubes about one inch
in diameter and six feet or more in length, the pipe D being about three inches in
diameter.
•
Referring now to features embodying the invention, each of the tubes E is
provided with a porous covering a, which preferably consists of an open-mesh
cloth, such as cheese cloth, which has been found .efficient, this cloth extending
entirely about the tubes, and being shown as having its two open ends lapped
together, and projecting below the tube! The cloth may be secured upon the tubes
by sewing, or in any other suitable manner, if desired, but this will probably not
be found necessary, as bringing the two ends of the cloth below the tubes together,

page_text: while wet, as shown, will be found sufficient to hold the cloth in place, and the
projecting edges below the tubes aid in distributing the cooling liquid from one pipe
to the next.
It will be understood that any other suitable porous material may be used for
covering the tubes, but it will be found that cheese cloth, or similar open mesh cloth,
is very efficient.
The construction provides a porous envelope which serves two purposes, viz., to
distribute evenly over the surfaces of the tubes the liquid received from the sprinkler ;:
second, to secure a non-heat-conducting covering over the tubes formed of a layer
of liquid of approximately even temperature, so that the tubes are protected against
sudden changes of temperature, and tubes of glass or similar fragile material may be
used without danger of fracture.
For the purpose of heating the cooling water to the desired temperature, when the
natural temperature is low, the liquid supply pipe may be passed through a heater L,.
shown in diagram, which may be of any form, or any other suitable means may be
used for this purpose.
Although I have described my present invention in connection with the
apparatus described in the Specification of the Patent above named, it will be
understood that the improvement is applicable also to similar apparatus of somewhat
different form.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. A condenser apparatus for condensing nitric acid and similar gases, by
evaporation of liquid from the condensing surface, and having fragile condensing
surfaces provided with a covering of thin cloth or other similar porous material
acting to distribute the condensing liquid over the condensing surface, and
provide a thin liquid envelope for protection of the fragile condensing surfaces,
substantially as described.
2. An apparatus. for condensing nitric acid and similar gases, having the
condenser tubes E of glass or other fragile material adapted to resist the
attack of the acid, and each provided with a covering a of cloth or similar porous
material, and means for sprinkling cooling liquid upon said tubes, substantially as
described.
3. A condenser apparatus for condensing nitric acid and similar gases by
evaporation of liquid from the condensing surface, and having fragile condensing
surfaces provided with a covering of thin cloth or other similar porous material
acting to distribute the condensing liquid over the condensing surface, and provide
a thin liquid envelope for protection of the fragile condensing surfaces, and means.
for heating the condensing liquid before its application to the condensing surfaces,
substantially as described.
Dated this 25th day of June 1896.
NEWTON & SUN,
Agents for the Applicant.