Improvements in or relating to the Manufacture of Ozone, and Apparatus therefor.
Year: 1895

page_text: Date of Application, 18th Dec., 1895
Complete Specification Left, 12th Sept., 1896-Accepted, 7th Nov., 1896
PROVISIONAL SPECIFICATION.
Improvements in or relating to the Manufacture of Ozone, and
Apparatus therefor.
I, CHARLES JOHN YARNOLD of 64 Upper Tulse Hill, Brixton, in the County
of Surrey, Gentleman, do bereby declare the nature of this invention to be as
follows:
This invention relates to the manufacture of ozone and apparatus therefor and
comprises the treatment of oxygen atmospheric oxygen or a suitable oxygen-
containing gaseous fluid in such a manner that a regulated proportion of the said
gas is rendered nascent or active and also is purified or freed from acid-forming
or injurious constituents, the treatment being so regulated that ozone is obtained
capable of use in the oxidation of organic matters and especially for bleaching,
sanitary purposes and purification generally. The ozone may be used for other
useful purposes. This invention comprises also an improved ozone-generator
bereinafter described..
In preparing ozone from atmospheric oxygen I prefer to first pass air through a
caustic alkali bath to free it from atmospheric impurities and thence through
drying and cooling apparatus. The air thus dried and cooled to say about
32° Fahrenheit is now passed through and along passages existing between
successive compound plates, these latter each comprising. a layer of metal foil
carried on or between sheets of insulating material and connected to a source of
electric energy, for instance to a "converter," producing a high potential
(preferably alternating), current of electricity or being connected to some other
source of high potential electric supply. Each sheet of insulating or dielectric
material is let into the sides or casing of the apparatus, which is also made of
insulating material, preferably slate. Or the apparatus may be otherwise arranged
as may be suitable; in any case the electrical discharges must not pass over the
edges of the layers of dielectric which should be capable of withstanding a moderate
pressure. A high potential alternating current conducted by the foils or metallic
layers produces between the dielectrics. a "silent discharge." The atmospheric
oxygen in being forced or pumped through the passages between the insulating
material is brought under the influence of the "silent discharge" (which through
a suitable opening may be viewed and tested as to temperature), and a given
percentage of oxygen is thereby rendered pascent or active; at the same time
certain oxides of nitrogen are formed, and are dealt with as hereinafter described.
Now regulation of the percentage of oxygen rendered active is very important in
bleaching and certain other operations and according to my invention, may be
effected as follows:-
(a) By the regulation of the amount of electric current passing through the
apparatus, for instance by means of a rheostat.
(b) By the regulation of the rate of passage of the gas between the dielectric
sheets in proportion to the number of alternations per second of the electric
current..
(c) The regulation of the temperature of the gas, before being subjected to the
silent discharge.
"
As regards the first method the amount of energy used as a "silent discharge
violet glow producing the
the onlus of the discharge a

page_text: maximum percentage of active oxygen or ozone. If I desire to attain a maximum
percentage of active gas I pass it through cooled to about 32° Fahrenheit, and at
a rate proportionate to the number of alternations of the current per second; for
example under certain typical conditions I have found it desirable to have such a
flow of the gas through the ozoniser that a given volume thereof should not remain
between two layers of the dielectric for any longer time than is needed to enable
the current to act on it and produce the ozone. If it is subjected to the current
for a longer period the results are inferior.
The gas having been subjected to the electric discharge may then pass upwards.
through one or more "de-acidifying baths," containing pumice or other suitable
porous material, and pure or distilled water, the whole so arranged that the gas in
going through comes into intimate contact with the water. The oxides of nitrogen
contained in the gas, being soluble, in water, will be retained in the "baths" as
nitrous and nitric acids thus:-
and the gas containing nothing but allotropic nascent or active oxygen or ozone
will pass on for utilization.
It is found that with an ozone-generator of the usual construction only, a portion
of the gaseous fluid passed through it is electrically ozonized, and consequently the
resulting ozone is diluted to an extent which seriously impairs its commercial value.
This inefficiency of the apparatus results because the sides of the passages are flat
and smooth and the flow of fluid between them is uniform and unbroken, so that
only such parts of each stream as are in immediate proximity to the surface of the
compound plates are sufficiently subjected to electrical influence, such influence, as
is well known, decreasing very rapidly as the distance from the electrified body
increases.
According to this invention the ozone generator is so constructed that the oxygen
or oxygen-bearing fluid is caused to swirl or eddy during its passage between the
compound plates. Thus a very large percentage of the fluid is subjected to the
desired intensity of electrical action, the yield of ozone being therefore much
greater and much less dilute than in ozone-generators as hitherto made, and the
waste of electric energy is diminished also.
For example the compound plates, or the surfaces of the plates may be corrugated
or ribbed in a direction transverse to that of the flow of fluid. Or there may be
projections or obstructions of any desired form made in or on the plates or on the
other walls of the passages, or placed in the spaces between them. Such devices
break up the current of fluid; they need not extend throughout the length or width
of the passages, but may occupy only a part or parts of the same. Preferably
wherever there is a projection at one side of a passage there should be a recess at
the opposite side; thus in a wavy corrugated plate the summits of the waves of
one plate should be opposite the hollows of the opposite plate.
な
This improved ozone-generator is advantageous not only for use in the process
hereinbefore described, but also for other processes wherein it is desired to produce
ozone electrically.
Dated this 18th day of December 1895.
:

page_text: Improvements in or relating to the Manufacture of Ozone, and
Apparatus therefor.
I, CHARLES JOHN YARNOLD, of 64 Upper Tulse Hill, Brixton, in the County
of Surrey, Gentleman, 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 the manufacture of ozone and apparatus therefor and
comprises the treatment of oxygen atmospheric oxygen or a suitable oxygen-
containing gaseous fluid in such a manner that a very large proportion of the ozone
is formed.
In the accompanying drawings
Fig. 1 is a diagram showing in elevation one arrangement of apparatus for use in
the production of ozone according to this invention.
Fig. 2 is a longitudinal section, slightly to one side of the centre-line, of an
improved ozone-generator and its appurtenances according to this invention.
Fig. 3 is a transverse section on the line 3-3 of Fig. 2.
Fig. 4 is an end elevation of a detail of Fig. 2, and
Fig. 5 is a perspective view of part of Fig. 2.
Like letters indicate like parts throughout the drawings.
With reference first to Fig. 1, in preparing ozone from atmospheric oxygen [
prefer to first pass air, by means of a blower A for instance, through a caustic alkali
or other suitable bath B to free it from atmospheric impurities and thence through
drying and cooling apparatus C. The air thus dried, and cooled to say about
32° Fahrenheit, is now passed along passages existing between compound plates in
an ozone-generator D such as is hereinafter described, these plates each comprising
a layer of metal foil carried on or between sheets of insulating material, and
connected to a suitable source of electric energy, for instance to a transformer
indicated diagrammatically at E, producing alternating currents of electricity of
high potential. The gas from the ozone generator may then be passed through a
de-acidifying bath in the chamber F.
Each sheet of insulating or dielectric material is preferably let into the sides or
casing of the apparatus, which is also made of insulating material, or the apparatus
may be otherwise arranged as may be suitable, care being taken that the electrical
discharges do not pass over the edges of the layers of dielectric. A high-potential
alternating current conducted by the foils of metallic layers produces between the
dielectrics what may be termed a "silent discharge." The atmospheric oxygen in
being forced or pumped through the passages between the insulating material is
brought under the influence of the "silent discharge," a portion of the oxygen
being thereby turned into ozone; at the same time certain oxides of nitrogen are
formed, aud may be dealt with in the manner described in the Specification of
Patent No. 12692 of 1895. The percentage of ozone formed is of course dependent
upon the supply of electric energy and of oxygen and still more upon the
temperature of the gas supplied. A low temperature in the gas and high tension
and frequency in the alternating current tend to increase the amount of ozone
formed.
It is found that with an ozone-generator of the usual construction only a portion
of the gaseous fluid passed through it is electrically ozonized, and consequently the
resulting ozone is diluted to an extent which seriously impairs its commercial value.
This inefficiency of the apparatus results from the sides of the passages being flat
and smooth so that the flow of fluid between them is uniform and unbroken, and
only such parts of each stream as are in immediate proximity to the surface of the

page_text: compound plates are sufficiently subjected to electrical influence, such influence, as
is well known, decreasing very rapidly as the distance from the electrified body
increases.
According to this invention the ozone generator is so constructed that the
oxygen or oxygen-bearing fluid is caused to swirl or eddy during its passage
between the compound plates. Thus a very large percentage of the fluid is
subjected to the desired intensity of electrical action, the yield of ozone being
therefore much greater and the resultant mixture much less dilute than in ozone-
generators as hitherto made; and the waste of electric energy is diminished
also.
For example the compound plates, or the surfaces of the plates may be
corrugated or ribbed in a direction transverse to that of the flow of fluid. Or
there may be projections or obstructions of any desired form made in or on the
plates or on the other walls of the passages, or placed in the spaces between them.
Such devices break up the current of fluid; they need not extend throughout the
length or width of the passages, but may occupy only a part or parts of the same.
Preferably wherever there is a projection at one side of a passage there should be
a recess at the opposite side; thus in a wavy corrugated plate the summits of
the waves of one plate should be opposite the hollows of the opposite plate.
With reference now to Figures 2, 3, 4 and 5 which illustrate one construction of
such a generator, the main casing D is a tube of rectangular cross-section through
which the oxygen-containing-fluid is caused to flow by some such apparatus as is
illustrated in Fig. 1.
Within the casing D is a series of compound plates J J₁; the plates are disposed
side by side in vertical planes parallel with the direction in which the oxygen-
bearing fluid passes through the generator, so that narrow spaces are left between
them (see Figs. 3 and 5) for the passage of the aforesaid fluid in ed.lying currents
the general direction of which is indicated by the arrows.
Each compound plate consists of two sheets of corrugated glass J2 J3 (Fig. 5.)
enclosing between them a layer K of silver foil or other metallic foil or coating,
extending not quite to the edges of the sheets except at one corner of the compound
plate where a tab or extension K' of the foil is provided to connect the layer with
one or other of two electric terminals L L' coupled to a transformer in a manuer
which need not be particularly described; the two sheets of glass enclosing the
foil may be secured together by cement applied to them near the edges of the
meeting surfaces. Each terminal comprises a metal rod L' held in a sleeve L³ of
insulating material extending transversely across the generator and secured in the
walls thereof. On each rod L³ is a binding-post L to enable it to be readily
connected to the aforesaid converter or other source of electric energy. The
compound plates J have their layers of foil electrically connected with the rod L'
of the teriniual I, whilst the plates J alternated with the plates J, have their
layers of foil connected with the opposite terminal L'. A good electrical
connection between the tabs K' and the rods L2 is afforded by screws L' which
pass through the sleeves L³ into the rods and at their outer ends are each encircled
by a washer L between which and the head L' of each screw one of the tabs K¹
is held. In order that the compound plates J J¹ may be retained at the desired
distance apart from each other their lower edges are placed between ribs D¹ formed
on the floor of the casing, and their upper edges are kept apart by fingers M
intercalated between the plates J J' and extending from a bar M' of insulating
material secured to each sleeve L³. D² D³ are bars or strips of insulating material
to prevent the compound plates from being accidentally displaced.
D is a hinged cover or lid provided with windows D' through which latter the
glow of the silent discharge is observable the amount of electric current being
regulated as aforesaid until the desired violet coloured glow ensues.
The bars D
drop into sockets in the wall of the casing D and are readily removable to enable
the compound plates to be lifted out of the generator, when desired, through the
opening ordinarily closed by the cover D*.

page_text: Preferably, expansion chambers N and N'are provided at each end of the ozone-
generator D as continuations of the passage-way for the gaseous fluid; or one such
chamber only is provided in which case it should be at that end of the generator D
at which the oxygen-containing fluid enters. These chambers should be of
greater cross-sectional area at the middle of their length than at their ends, and
It is found
conveniently of some such form as is indicated in Figures 2 and 4.
that their use equalizes the flow of the oxygen-containing fluid through the spaces.
between the different pairs of compound plates and also that they equalize the
fluid pressure in the several spaces of the generator and aid materially in making
the product uniform. To enable the temperature of the gas to be observed as it
enters and leaves the generator D, a thermometer is inserted therein so that the
bulb is about at the centre of the current of gas flowing through the apparatus and
the graduated portion of the thermometer stem is extended so as to be readable.
from the outside of the generator.
In the example chosen for illustration a thermometer O is inserted through a.
stuffing-box N in the wall of each chamber N N'.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
1. An ozone-generator of the kind herein above described which has projections
or obstructions for the purpose described, in the passages traversed by the fluid
treated in it.
2. An ozone-generator such as D with corrugated plates, such as J J
substantially as and for the purpose described.
3. The combination and arrangement of parts constituting an ozone-generator
substantially as and for the purpose described and illustrated in the accompanying-
drawings.
Dated this 10th day of September 1904
CHARLES JOHN YARNOLD.
Boult & Wade,
Agents for the Applicant.
CHARLES JOHN YARNOLD.
Boult & Wade,
Agents for the Applicant.