Improvements in and Apparatus for Producing Ozone.
Year: 1896

page_text: Date of Application, 29th Dec., 1895-Accepted, 27th Feb., 1897
COMPLETE SPECIFICATION.
Improvements in and Apparatus for Producing Ozone.
I, JAMES YATE JOHNSON of 47 Lincoln's Inn Fields, in the County of London,
Gentleman do hereby declare the nature of this invention (which has been communi-
cated to me from abroad by The Electric Rectifying and Refining Company, a company
organized under the laws of the State of New Jersey, United States of America,
baving an office at 552 Federal Street, Camden, New Jersey aforesaid and doing
business in Philadelphia, Pennsylvania) and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
This invention consists of a process of producing ozone. gas from oxygen whereby
both the quantity of ozone gas produced and its purity are greater than is the case
with processes as hitherto known.
The process according to this invention consists essentially in subjecting oxygen
gas to un electric current in the form of a brush discharge, the oxygen gas being,
by preference. at a low temperature while it is being subjected to the action of
the current. The invention also comprises 'apparatus for carrying ont the process
according to this invention all as hereinafter fully described.
In the accompanying drawings,
Fig. 1 is a side view, partly in section, of apparatus constructed in accordance with
this invention, for the production of ozone.
Fig. 2 is a longitudinal section, on a larger scale, of the generator proper. Fig. 3
is a transverse section of the same, and
Fig. 4 is an exaggerated view. illustrating more clearly than the other figures the
character of the conducting surfaces with which the generator is provided.
A represents a tank, or reservoir, for containing oxygen which may be derived
from any suitable source. This tank is connected, by means of a pipe a to the
ozone generator C, between which and the tank A, is a refrigerating, or cooling,
tank B. through which the pipe a passes on its way to the generator C, the said
pipe a being preferably spirally coiled in the tank B and being surrounded therein
by 'a refrigerating, or cooling, medium, such, for example, as ammonium nitrate
aud water.
Instead of passing the oxygen gas through a cooling medium the said gas may
be compressed, and after permitting the compressed gas to cool to any desired
extent, it may then be permitted to expand, either directly into the ozone
generator, or into a supply chamber therefor, thereby cooling it to the desired
degree.
The generator C consists of a casing c, of dielectric material, preferably glass,
and preferably also in the form of a tube, or pipe, closed at each end by caps c
that at one end of the casing being provided with apertures and e, and that
at the other end of the casing being provided with apertures and c
Within this outer casing e is another casing, or box, b, preferably of metal and
centrally supported within the outer casing, and of smaller external diameter than the
internal diameter of the outer casing, so as to provide a uniform space between
the two.
Within the inner casing is a spraying device consisting, for example, of a perforated
metal tube closed at that end which is within the inner casing, but open at the
outer end, the tube passing through the aperture c" in one of the caps c', which

page_text: aperture is preferably provided with a suitable stuffing box, the outer end of the tube
being connected with any suitable supply of cooling fluid, which may be admitted to,
or cut off from, the tube d as desired, by means of a valve 6.
Connected to the inner casing b preferably at one end is a discharge pipe e which
passes through the packed aperture c and is for draining the interior of the said:
casing and thereby preventing the accumulation therein of fluid in suob quantity as
would interfere with the spraying action of the perforated tube d..
Communicating with the space between the inner and outer casings of the gonerator
is a pipe which is fitted to the aperture c which serves to convey the ozone gas to
any suitable reservoir, or treating chamber, the oxygen gas supply pipe a passing
through the aperture in the opposite cap c of the generator.
The outer, surfaces of both the inner and outer casings of the generator are coated
with a layer of powdered or granulated carbon, lead, dust, or other material which
will given surface of roughened, or granulated, form presenting a multiplicity of points
or protuberances and produce a brush discharge consisting of a great number of sparks
passing and repassing in rapid succession, giving the appearance of a continuous flow
of electricity between the two coatings.
The said coatings may be applied in any suitable way for example by first
applying an adhesive and then thinly sprinkling the powdered or granulated inaterial
thereon. To the said coatings are connected the terminals of the secondary coil
of a stop-up transformer, supplied with a current of electricity, preferably an
alternating current. The terminal k is connected to the outer surface of the
inner casing band the terminal k is connected to the outer surface of the onter
casing, c, so that when the current of electricity is turned on, a brush discharge is
induced between the coatings of the inner and outer casings through the dielectric
outer casing, and the oxygen gas passing through the annular space between the
two casings is subjected to the action of this brush discharge, the low temperaturė
of the gas being maintained by the cooling fluid which 'is sprayed upon the inner
casing from the tube d...
By thus subjecting oxygen gas to an electrical current in the form of an induced
brush discharge, ozone of a very high degree of strength can be economically and
rapidly produced. The process is facilitated by a low. temperature of the oxygen
gas, hence it is preferred in all cases to cool the said gas as aforesaid.
Temperatures below zero Fahrenheit may be used, and, as a rule; the lower the
temperature, the better the result.
It is preferred in carrying out this invention to use oxygen gas of as pure a
character as can be manufactured on à commercial scale, within the necessary
limit of cost, although this invention may be carried out successfully even if the
oxygen gas be diluted, or adulterated, to some extent by admixture with air, or
with other gases.
Although the hereinbefore described process and apparatus for generating ozone
are particularly adapted for use in purifying and decolorizing saccharine and other
liquids, and in parifying, rectifying, decolorizing and deodorizing alcoholic, and
other liquids, they are also capable of general application wherever ozone gas is
.required.
Although it is necessary in all cases to make the outer casing dielectric, thé
inner casing may, or may not, be dielectric. It is however preferred to make the
inner casing of metal, or equivalent material, especially where the cooling medium is
sprayed against it, in order that it may the better withstand the shocks of the
streams of cooling fluid impinging on it.
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 :-
I
1. The production of ozone gas, by subjecting oxygen gas to the action of an
electrical brush discharge, substantially as herein before described.
2. The production' of ozone gas, by subjecting oxygen gas to the action of an

page_text: electrical brush discharge, the said oxygen gas being previously reduced to a low
temperature or maintained at a low temperature during such treatment or both
previously reduced to a low temperature, and maintained at a low temperature
during such treatment, substantially as herein before described.'
3. In apparatus for generating ozone gas, the combination of separated casings,
one or both being dielectric, and each provided with a coating of material suitable
for inducing an electrical brush discharge, means for causing a flow of oxygen
through the space between said casings, and means for conveying an electric
current to one, and away from the other, of said coatings, substantially as herein-
before described.
4. In apparatus for generating ozone gas, the combination of separated casings,
one or both being dielectric, und each having a coating of material suitable for
inducing an electrical brush discharge, meaus for convoying an electrical current
to one, and away from the other, of said coatings, means for causing a flow of
oxygen gas through the space between the casings, and means for reducing the
temperature of said gas before it enters the generator or means for maintaining
said gas at a low temperature during its passage through the generator or both,
means for reducing the temperature of said gas before it enters the generator,
and means for maintaining the said gas at a low temperature while it is passing
through the generator, substantially as hereinbefore de-cribed.
5. In apparatus for generating ozone gas, the combination of the inner and
outer casings mounted so as to leave a space between the two, the outer case
being dielectric, and each casing having an exterior coating of material suitable
for inducing an electrical brush discharge, with an inlet for admitting oxygen gas
to the space between the inner and outer casings, an outlet from the sail space,
and connections between the conducting coatings of the two casings and a suitable
generator of electricity, substantially as herein before described.
6. In apparatus for generating ozone gas,: the combination of the inner and
outer casings mounted so as to leave a space between the two, the outer casing
being dielectric and each casing having an external coating of material suitable for
inducing an electrical' brush dischargo, connections between said external coatings
and a suitable source of electricity, a perforated pipe extending within the inner casing
and having connection with a supply of cooling fluid, a pipe for withdrawing the
cooling fluid from the said inner casing, and means for causing a flow of oxygen gas
through the space between the two casings, substantially as hereinbefore described.
7. In apparatus for generating ozone gas, the combination of the inner and outer
casings mounted so as to leave a space between the two, the outer casing being.
dielectric, and each casing having an external coating of material suitable for
inducing an electrical brush discharge, connections between the said coatings, and an
electric generator, a pipe for supplying oxygen gas to the space between the two
casings, and a refrigerating tank through which the oxygen supply pipe passes on its
way to the generator, substantially as hereinbefore described.
8. In apparatus for generating ozone gas, the combination of the inner and outer
casings mounted so as to leave a space between the two, the outer casing being
dielectric, and each casing, having an external coating of material suitable for
inducing an electrical brush discharge, connections between the said coatings and 'a..
generator of electricity a spraying device for introducing jets of cooling fluid within
the inner casing, a source of oxygen gas supply, a pipe leading therefrom to the,
space between the two casings, and a refrigerating vessel through which the said
pipe passes on its way to the generator, substantially as herein before described...
Dated this 29th day of December 1896.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents