Improvements in Apparatus for Converting Nitric Peroxide into Nitric Acid.
Year: 1897

page_text: Date of Application, 4th Aug., 1897-Accepted, 25th Sept., 1897
COMPLETE SPECIFICATION.
Improvements in Apparatus for Converting Nitric Peroxide into
Nitric Acid.
I, OSCAR GUTTMANN, Consulting Engineer, of 12, Mark Lane, in the City of
London 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 apparatus hitherto employed for converting into nitric acid the nitric
peroxide resulting either from the denitration of waste acids or in the manufacture
of nitrocompounds, arsenic acid, and the like, obtain the moisture necessary for
this conversion only from the steam, that is used in the denitration. The nitric
acid resulting therefrom is coloured green through the unavoidable presence of
large quantities of nitric peroxide, and is of inferior strength, because in the
condensing apparatus all the moisture of the steam condenses, and in the absorbing
apparatus large quantities of liquid are required to absorb all the escaping gases.
The object of my present invention is to provide means, whereby the whole of
the nitric acid formed is brought by a constant stream into contact with the
ascending unconverted and uncondensed gases, thus constantly enriching the
acid and obtaining the maximum possible strength. In order to obtain this object
I have constructed an apparatus, of which Figure 1. is a plan, Figure 2. a
longitudinal section, and Figure 3. an end view.
A. is a denitration apparatus of the usual kind from which the nitric peroxide
gases issue through a pipe a., and go into an earthenware receiver B., which is
filled with coke, broken glass, or with balls, as described in my Patent No. 14774
of July 3rd, 1896, and serves to prevent breakage of the apparatus through the
gases being too hot. The gases pass from this receiver out through the pipe b.
and are drawn out by means of an earthenware ejector C., which is worked by
compressed air blowing in at c., and thereby on the one hand assists the work
of the denitrating apparatus and on the other hand blows the air required for
the transformation of nitric peroxide into nitric acid through the whole of the
apparatus. The nitric peroxide gas now passes into two or more vertical towers
or series of pipes D., D₁, which are filled with coke, broken glass and the like,
or the balls described before, whilst a fine stream of water trickles down from
the top of these towers. The nitric peroxide gases are thereby transformed into
The liquid
nitric acid, and this will be partly liquid and partly gaseous.
portion runs into a distributing tank E., the gaseous portion issues through the
pipe F. into a condensing apparatus G., which is by preference, what is known
5 as the Guttmann-Rohrmann water-cooled battery shown in the drawing. The dis-
tributing tank E. is an ordinary earthenware vessel, which has a number of sockets e.
and on the inside corresponding to each socket small screens f., which are all
of the same height. The liquid runs into this tank through the cover g., and
when it has reached the height of the screens, runs over into each screen in equal
o quantities, being carried away to the top of the condensing apparatus by the
small sockets e. and the pipes h. attached to them. The condensing annaratus
for this purpose has instead of plain bends, connecting one pipe to the other,

page_text: bends i. having small sockets k. A similar socket 7. and pipe m. leads to the
receiver B., so that this also obtains its share, of acid. The nitric acid gases
passing into this condensing apparatus meet on their upward and downward move-
ment a constant stream of liquid acid, which thereby gets richer and richer.. "Those
quantities of nitric acid gas, that have not been condensed in this apparatus, go
by means of the connecting piece' and pipe r. into a condensing tower, such as
a Lunge-Rohrmann's, a coke tower or the tower H. filled with balls as patented
under No. 14774 of 1896, where they again meet a small stream of water in order
to prevent any further escape of gas. The acid condensed in the tower H. with
the acid from the towers D. and D), runs by means of a T piece I. into the same
distributing tank E. The whole of the acid thus condensed and formed issues
from the condensing apparatus through the pipe K. into the collecting vessel L.,
from which it can be drawn into carboys and the like at 2. The liquid acid
condensed and formed in the receiver B. flows by means of the pipe n. to the
vessel L. The pipe o. serves to carry off to the tower H. any gases, that may
form in the collecting vessel L.
'
By this process the acid will not only be of the highest possible-strength, but also
the current of the acid gases is suitably retarded; but this means sufficient time
is allowed for condensation and thorough mixing with the moisture and air, and
the gases are entirely converted into nitric acid.
4
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare, that what
I claim is
An apparatus for th conversion of nitric peroxide gases into nitric acid for
the purpose of bringing the whole of the acid formed into contact with the
ascending unconverted and uncondensed gases substantially as described. and
illustrated in the accompanying drawing.