Improvements in the Manufacture or Production of Ozone and in Apparatus therefor.
Year: 1897

page_text: Date of Application, 3rd May, 1897
Complete Specification Left, 28th Dec., 1897-Accepted, 26th Mar., 1898
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture or Production of Ozone and in
Apparatus therefor.
I, MARIUS OTTO, of 8 Passage Gourdon, Paris, France, Doctor, do hereby
declare the nature of this invention to be as follows:-
Most apparatus heretofore proposed for producing ozone by means of high-tension
electric currents (e.g., the Otto, Siemens, and Andreoli ozonizers) are characterized
by the fact that, in order to obviate dangerous short-circuiting, it is necessary to
separate, by means of glass, mica, or some other dielectric, the two electrodes
between which the electric discharge takes place and the gaseous body to be ozonized
circulates. i
The dielectrics are very frequently a cause of accidents, especially when glass is
employed, but if they are not used, unless currents of very high potential and very low
quantity-supplied, for example, by an electrostatic machine--are employed, it is
uot long before arcs are produced between the electrodes of opposite signs, whereby
the said electrodes are rendered useless. The formation of such arcs is due
principally to the. reduction of the resistance of the gaseous body by the heating
thereof.
Apparatus according to my invention allows of the use, for the production of
ozone, of currents of high tension produced by means of transformers of ordinary
construction, without there being any fear of short-circuiting between the
electrodes, which would render the electrodes useless. In producing ozone there-
with I allow the flow of electricity between the electrodes to take place only during
a very short time, and I cause the distance which separates the electrodes to vary
rapidly, thus increasing the resistance of the gaseous body until it becomes infinite
so soon as short-circuiting threatens to occur.
I call the apparatus which enable me to effect this phenomenon, "ozonizers with
movable electrodes."
It will be understood that the construction of my ozonizers with movable
electrodes may vary within wide limits.
In all cases where two electrodes situated at a very great distance apart, and
connected respectively with a source of supply of current of, high potential, are
moved nearer to each other. to a sufficient distance apart, discharges will take place
between them, and if this distance be gradually increased until the resistance
offered by the path along which the discharge must take place be such that the
potential of the electrodes cannot overcome it, the phenomenon will take place the
production of which is the principle on which my apparatus is constructed.
One of the most simple arrangements consists of two parallel conducting circles
or discs from which a series of sectors are cut out. The centres of the two circles
or discs are in one and the same axis; the two circles or discs are connected
respectively to each of the poles of a high-tension transformer. The surfaces facing
one another may be plane, undulating or corrugated, or bristling with points.
If one of the circles or discs be fixed, and the other circle or disc. have rotary

page_text: motion imparted to it, a discharge will take place each time two full sectors come
opposite to each other, and will cease as soon as the sectors move away from each
other. The use of points is impracticable for very high tensions.
By adding condensers, the capacity of the apparatus can be increased.
Dated this 3rd day of May 1897.
F. WISE HOWORTH,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.
Improvements in the Manufacture or Production of Ozone and in
Apparatus therefor.
I, MARIUS OTTO, of 8 Passage Gourdon, Paris, France, Doctor of Physical
Sciences, 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:―
Most apparatus heretofore proposed for producing ozone by means of high-tension
electric currents (e.g., the Otto, Siemens, and Andreoli ozonizers) are characterized
by the fact that, in order to obviate dangerous short-circuiting, it is necessary to
separate, by means of glass, mica, or some other dielectric, the two electrodes
between which the electric discharge takes place and the gaseous body to be ozonized
circulates.
The dielectrics are very frequently a cause of accidents, especially when glass is
employed, but if they are not used, unless currents of very high potential and very low
quantity supplied, for example, by an electrostatic machine-are employed, it is
not long before arcs are produced between the electrodes of opposite signs, whereby
the said electrodes are rendered useless. The formation of such arcs is due
principally to the reduction of the resistance of the gaseous body by the heating
thereof.
Apparatus according to my invention allows of the use for the production of
ozone, of currents of high tension produced by means of alternators and trans-
formers of ordinary construction, without there being any fear of short-circuiting
between the electrodes.
-
The apparatus has the following characteristics:-
1. The electrodes (at least one half of them) are movable.
2. The electrodes are constructed only of materials which offer every guarantee of
resistance and strength which apparatus intended to be used on a commercial scale
for a long period should be required to possess.
3. The electric discharge takes place directly into the air or into the oxygen
between metal parts which are raised to different potentials without any dielectric
whatever being interposed between the said metal parts. The movability of the
electrodes (or at least of half of the same) has for object to allow the discharge
to take place only during a very short time in such a manner as to avoid all heating
of the electrified mass, and consequently all subsequent short-circuiting.
I will consider, by way of example, the case of two electrodes connected
respectively with the two poles of a source of current of high potential and situated
at such a distance from each other that electric discharge cannot take place between
them. If the electrodes be moved to within a sufficiently small distance of each
other discharge will take place. Then by increasing this distance gradually, the
discharge will cease at the moment when the resistance offered by the path through
which the discharge has to travel, is such that it cannot be overcome by the
difference of potential existing between the electrodes.

page_text: It will be understood that this succession of phenomena can be produced in
practice by means of various arrangements. One of the most simple consists in
employing two parallel conducting circular discs in which are cut out a series of
parallel or slightly inclined sector shaped holes, similar to the blades of a screw
propeller, the centres of the two discs being situated on the same axis. The two
discs are connected respectively to the two poles of a high-tension transformer.
The surfaces of the discs which face each other may be plane, undulating or
bristling with points. One of the discs being fixed, then if the other disc have
imparted to it rotary motion, a-discharge will take place each time the two full
sectors come opposite each other and the discharge will cease when the discs move
away from each other, or turn relatively to each other sufficiently to bring the full
sectors in one disc opposite the holes in the adjacent disc.
Instead of discs, two surfaces of any other shape may be employed, which, instead
of having a uniform motion, might have imparted to them an alternating rectilinear
motion or an alternating circular or oscillating motion. The results of my ex-
periments have led me to confine myself practically to the two following types of
ozonizers having movable electrodes which are illustrated respectively in Figs. 1
and 2, and in Figs. 3 and 4 of the accompanying drawings.
The apparatus illustrated partly in front elevation and partly in longitudinal
section in Fig. 1, and partly in end elevation and partly in cross section in Fig. 2,
comprises a strong framing F1, F2, 13, F* etc. of cast iron of octagonal shape. The
sides or lateral walls are formed alternately with projecting portions 3 etc,
and with re-entering portions 11, 12, 13, etc. The latter are provided with wings or
ribs similar to those employed in radiators.
Inside the framing F, F, F3, F4 and carried by a shaft A', A³, through the
medium of an
insulating disc or ring I, a metal disc D', D' which is capable of
rotating and which carries a series of plane and undulating or corrugated sectors,
or sectors bristling with points, or provided with metallic brushes or wires S¹, S³, S³
etc. of aluminium or platinum.
A pulley P fixed upon the shaft A', A2 allows of rotary motion being imparted to
the disc. Two windows G1 G2 allow of the interior of the apparatus being inspected.
The window pane G¹ is formed at the centre with a hole through which passes a
metal rod provided at its inner end with a brush C arranged to supply electricity
to the disc D1, D2, and at its outer end with a terminal P. To the latter there is
fixed one end of a conductor the other end of which is connected to one of the poles
of a high tension transformer the other pole of which is connected to the metal
framing F F F³ F* by means of conductor P³, fixed to one of the fixing or sealing
bolts of the apparatus.
The gaseous mass of air or of oxygen to be ozonized enters the apparatus through
a tubular union and is distributed uniformly by means of a perforated plate K,
and follows the paths indicated by the arrows and issues, after having been subjected
to the action of the electric discharge, through the tubular union . When the
apparatus is in operation, it will be easily seen that, by reason of the inequality of
the distance separating the sectors S1, S2, S3 etc. from the parts 11, 12, 13 etc.,
and v¹, v, 3 etc. of the cast iron framing, the discharge takes place and ceases at
very close intervals, and that it passes constantly from one point to another on the
sectors S1, S2, S3 etc. In this manner, the formation of short circuits is completely
obviated.
The movable portion of the apparatus illustrated partly in elevation and partly
in longitudinal section in Fig. 3, and partly in plan and partly in horizontal section
in Fig. 4, comprises two or more metal screws working inside a cast iron cylinder
which is provided like the framing of the apparatus just described with alternately
projecting parts 11, 12, 13 etc., and re-entering parts v1, v2, v3³, etc.
The cylinder F1, F2, F3, F4, is closed at its ends by means of covers provided with
windows G¹, G etc. Each screw H¹, H³, is constituted by a series of conducting
points of platinum or aluminium or the like held in place by means of two inter-

page_text: twisted wires fixed on a cylinder D¹, D³, of porcelain or other suitable insulating
material.
A brush C rubbing on a metal ring m fixed on the base of one of the porcelain
cylinders, supplies the current to the metal points of the screws. This brush is
carried by a rod that is provided with a terminal P₁ and extends through one of the
windows GGs that close the cylinder.
One of the poles of a high tension transformer is connected to the terminal P
.and the other pole communicates directly with the cylinder F, F, F3, F4 by means
of a wire P2 connected to, one of the bolts used for fixing one of the metal end
covers to the cylinder.
The two screws H and H are separated by a disc or sleeve E which constitutes
a contracting or throttling device. The object of this disc is to regulate the speed
of the gaseous current in the several parts of the apparatus and to subject the air
oxygen to. be ozonized and which enters the cylinder through, the tubular
union and passes out through the tubular union t, in the most uniform manner
possible to the electric discharge.
or
.
The shaft A', A which carries the screws, is provided with a toothed wheel
which allows of rotary motion being imparted to it and to the said screws connected
therewith.
When the apparatus is in operation, the discharge takes place between the
points that constitute the screw, and the re-entering-points 11,73, 13 etc. of the
cylinder, the starting and extinguishing of the discharge taking place at very
close intervals and in such a manner as to completely avoid all, short-circuiting.
At 50,000 volts it is advantageous, from the point of view of simplicity of con-
struction of the apparatus, to employ, instead of the metal points, a simple cast iron
screw, having a thread of triangular section.
In apparatus having movable electrodes as hereinbefore described, the distance
separating the movable parts from the fixed parts which are nearest to them, that
is to say, the distance through which the electric discharge must travel, varies with
the potential. By way of example, I may state that with 18000 volts, the said
distance should be about three centimetres. These apparatus are usually made of
cast iron, but instead of that metal, any other materials may be used, such as wood,
sheet metal, porcelain etc. It is essential if a non-conducting material is employed,
that it should be covered with metal at the point where the electric discharge is to
take place.
In order to render the materials employed in the construction of my ozonizers,
proof against the action of ozone, they may be covered with a coating or layer of
non-oxidizable metal such as platinum, gold, etc., or they may be protected by
means of a suitable covering or coating of enamel, varnish, etc.
The apparatus
according to my invention such as shown in Figs. 1, 2, 3 and 4 and also analogous
apparatus having movable electrodes may not only be utilized in the production of
ozone, but may also be used for all operations. of combining or decomposing gas
which necessitate the use of electric discharges; for example, for the purpose of
combining nitrogen and acetylene with the object of forming hydrocyanic acid;
for the purpose of combining nitrogen and oxygen with the object of forming
nitrated products; for the purpose of combining nitrogen and hydrogen with the
object of forming ammonia, etc.
These various reactions require varying potentials. Thus, very energetic dis-
charges of sparks are necessary for the production of hydro-cyanic acid, whilst a
simple discharge is favourable to the formation of ammonia. One of the great
advantages of my apparatus with movable electrodes consists in that the nature
and the intensity of the electric discharge can be varied within wide limits without
danger.
It is obvious that two or more apparatus of the kind shown in Figs. 1 and 2, or
in Figs. 3 and 4 may be arranged in series or in parallel.
Having now particularly described and ascertained the nature of the 'said inven-

page_text: tion and in what manner the same is to be performed I declare that what I
claim is:-
1. In apparatus for producing electric discharges at high tension with the aid
of commercial alternators and transformers for the purpose of effecting operations
such as polymerisation, combination, or decomposition of gases, the use of electrodes
that are movable relatively to one another and are so constructed and arranged as
to gradually produce and extinguish electric discharges at very close intervals and
in such a manner as to prevent the formation of short circuits as set forth.
2. Electric discharge, apparatus with moveable electrodes constructed and
arranged substantially as herein before described with reference respectively to
and shown in Figs. 1 and 2; and in Figs. 3 and 4 of the drawings annexed and
suitable for the manufacture of ozone, and other substances as set forth.
001
100x
F. WISE HOWORTH,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.