Improved Apparatus for the Condensation of Nitric Acid and other Vapours.
Year: 1894

page_text: Date of Application, 11th Sept., 1894--Accepted, 20th Oct., 1894
ICommunicated from abroad by EDWARD HART, Professor of Chemistry, of
Easton, in the State of Pennsylvania, United States of America.]
Improved Apparatus for the Condensation of Nitric Acid and
other Vapours.
I HENRY EDWARD NEWTON of The Office for Patents, 6 Bream's Buildings,
Chancery Lane, in the County of London, Patent Agent, 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 an improved apparatus for the concentration of vapours,
and especially for the condensation of nitric and similar acids from gaseous into
liquid form. The improved apparatus depends upon the principle of the division
of the current of vapour, so as to secure a large cooling surface, and diminish the
friction of the gases, and that of the high degree of refrigeration secured by the
evaporation of liquid from the surface of pipes, or equivalent conveyors, through
which the gases are passed.
For a full understanding of the invention, a detailed description of an apparatus
for condensing nitric acid, embodying the invention in the preferred form, will now
be given in connection with the accompanying drawing, showing the apparatus in
diagrammatic side elevation, and the features forming the invention then specifically
pointed out in the claims.
In the drawing, A is the retort, which may be of any suitable form, and from
which the vapour 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 pipes, 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 pipes E may be exactly horizontal, or inclined in
either direction, but for the best results, they are preferably inclined slightly, as
shown, towards the pipe D, at their inlet ends, so that the acid will flow back
through the pipes 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, while the uncondensed vapours
pass onward through the pipes E into the pipe F, and are thus discharged at the
top, where they may be condensed by any suitable means. By this method of
returning the acid to the vessel C, the acid is boiling hot as it is syphoned off into
the receiver, so that in the case of nitric acid, no red oxides of nitrogen or chlorine
shall be dissolved in it, but it is delivered in a very pure condition. While,
however, this construction is preferable, and in itself forms a part of the invention,
it will be understood that the receiver may be connected with the pipe F, and the
pipes E be horizontal, or inclined towards the pipe F. The pipes E, however,
should be approximately horizontal, so as to expose the pipes throughout their
length, to the action of a sprinkler placed above them, and to secure the prolonged
cooling action which results from a slow current of the condensed or partially
condensed liquid. Above the pipes E is the water supply pipe G, perforated or
slotted in any suitable manner, to supply the amount of cold water required by
sprinkling the same over the pipes E.
As the pipes E are quite hot, the water is evaporated therefrom, and by
constructing the pipe G so as to properly regulate the water supply, all, or
substantially all, of the water may be evaporated from the pipes, so as not to
necessitate provision for carrying off the surplus water. It will be understood,
however, that it is not. essential that all the water should be evaporated, and a

page_text: trough K, with drain pipe k, may be used below the pipes E, as shown, to carry off
any surplus water, or other suitable provision be made for this purpose.
The vessel C and vertical pipes D, F are preferably made of stoneware, glass, or
other similar material, suitable to resist the attack of the acid, and the pipes E are
preferably made of glass or other material suitable to resist the attack of the acid,
and, at the same time, conduct the heat from the gas quickly, so as to secure the
proper cooling action.
The number, size, and length of the pipes, D, E, F, and other parts of the
apparatus, will be varied as is necessary, in order to secure perfect condensation of
the gas, it being obvious that this will depend somewhat upon the size of the retort
and other circumstances, and such variation being within the knowledge of those
skilled in the art.
A construction which has been found efficient is produced by making the vertical
pipe D about three inches in diameter, and the pipes E about one inch in diameter,
and six feet or more in length, the inclination of the pipes E being about one inch
in six feet.
It will be seen that by thus dividing the current of vapor, large cooling surfaces
are secured, and the friction of the gas is diminished, and that by the evaporation
of the water a large and rapid absorption of heat is secured.
While the invention has been described in connection with water as the cooling
medium, as this is the liquid commonly used, it will be understood that any other
suitable liquid may be used for this purpose. The apparatus has been described in
connection with the preparation of nitric acid, but it will be understood that the
apparatus is applicable also to the condensation of other similar gases.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me
from abroad, I declare that what I claim is :-
1. The combination with a retort and receiver, of a series of pipes between
which the vapor is divided on its path from the retort to the receiver, and means
for sprinkling liquid upon said pipes, substantially as described.
2. The combination with a retort and receiver, of horizontal or inclined pipes
arranged one above the other, between which the vapor is divided on its path from
the retort to the receiver, and a perforated liquid supply pipe above said pipes,
substantially as described.
3. The combination with a retort, of pipes arranged one above the other between
which the vapor is divided on its path from the retort, said pipes being inclined
slightly towards the inlet end for the vapor, a perforated liquid supply pipe above
said pipes, and a receiver for the condensed liquid connected with the inlet ends of
said pipes, substantially as described.
4. The combination with a retort and receiver, of a vessel receiving the vapor
from the retort, a vertical pipe from said vessel, a series of pipes connecting with
said vertical pipe at one end, and arranged one above the other, and inclined
slightly towards said vertical pipe, a vertical gas escape pipe connecting with the
other ends of said inclined pipes, and a syphon between said vessel and receiver,
substantially as described.
5. The combination with retort A, of the vessel C, connected with said retort,
pipe B connecting said retort. and vessel, vertical pipe D connected at its base
with said vessel C, vertical pipe F, pipes E connecting said vertical pipes D, F,
and arranged one above the other, perforated liquid supply pipe G above said
pipes E, and a syphon for conducting the condensed acid from the vessel C to a
receiver, substantially as described.
Dad his 1st d...
ben1004
NEWTON & SON,
Agents for the Applicant.