Improvements in Apparatus for the Production of Ozone.
Year: 1896

page_text: Date of Application, 14th May, 1896
Complete Specification Left, 22nd July, 1896-Accepted, 29th Aug., 1896
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for the Production of Ozone.
I EMILE ANDREOLI of 147 Cold Harbour Lane Camberwell in the County of
London Journalist do hereby declare the nature of this invention to be as
follows:-
This invention relates to improvements in the construction of apparatus for
the production of ozone on a large scale, the said apparatus being so constructed
as to reduce the rise of temperature usually produced by the electric effluvia,
and to be capable of being worked continuously for long periods of time, while
in some forms of construction, a prolonged contact of the air or of the oxygen
or other gas to be ozonised with the glow of the silent discharge at the electrodes
is also obviated.
According to my invention the apparatus is made with two sets of electrodes,
each electrode being formed of a shallow metal box which may be made with its
sides either square in shape or elongated and narrow. The said electrodes may
be provided externally with points such as are described for example in the
Specification of my prior Patent No. 17426 of 1891 and contain water or other
cooling liquid so as to constitute coolers. The cooling liquid is supplied to the
hollow electrodes from a suitable source of supply and may be renewed from
time to time, or it may be caused to constantly circulate through the said
electrodes by means of suitable pipes feeding from tanks or cisterns.
Between each electrode is a separator made of a convenient dielectric and the
electrodes are as usual connected alternately to the poles of a transformer or
other high electric tension apparatus.
The electrodes are enclosed in a case or receptacle which is provided at one
end, or at the base, with a chamber forming an air chamber into and through
which the air or oxygen or other gas to be ozonised is forced and spread out
in a uniform manner by means of baffle plates, pipes, or other distributors so that
an equal volume of the said gas will pass between each pair of electrodes. At
the other end or top of the said case or receptacle is a chamber constituting an
ozone chamber for receiving the ozonised air or oxygen or other gas from the
electrodes; this chamber permits of the withdrawal of the ozonised gas from the
influence of the electric effluvia which would otherwise heat it and tend to
decompose it. The sets of electrodes are independent of each other and can be
readily and rapidly withdrawn from the receptacle when required for example
for repairs or for inspection.
The electrodes are situated between the air chamber and the ozone chamber
in such a manner that no space is left on their active surfaces which is not in
contact with the air or oxygen or other gas forced into the apparatus.
Dated this 14th day of May 1896.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.

page_text: Improvements in Apparatus for the Production of Ozone.
I EMILE ANDREOLI of 147 Coldharbour Lane Camberwell in the County of
London Journalist 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 improvements in the construction of apparatus for
the commercial production of ozone, the said apparatus being so constructed as
to present a large electrifying surface and to reduce the rise of temperature
usually produced by the electric effluvia, and to be capable of being worked
continuously for long periods of time while in some forms of construction according
to my invention a prolonged contact of the air or of the oxygen or other gas
to be ozonised with the glow of the silent discharge at the electrodes is also
obviated with the same object, namely, to prevent undue rise of temperature.
According to my invention the apparatus is made with two sets of electrodes,
each electrode being formed of a shallow metal box with flat sides which may be
made of any suitable shape such as either square or elongated and narrow. The
said electrodes are preferably provided externally with points formed for example
by serrated strips or wires, such as are described in the Specification of Letters
Patent No. 21794 of 1892 granted to me although such points may be dispensed
with if desired. The said electrodes contain water, or other refrigerating liquid
which is supplied to the hollow electrodes from a suitable source and may be
renewed from time to time or be caused to constantly circulate through the said
electrodes by means of suitable pipes feeding from tanks or cisterns.
Between each electrode is a separator made of a suitable dielectric and the
electrodes are connected to the poles of a transformer or other electric apparatus
giving a current of high tension and rapid alternations.
Figure 1 of the accompanying drawings represents in perspective an ozoniser
constructed according to my invention. A is the box, B the cover, C C C are the
sight holes, DD the reservoirs, E E inlets for water; F F the outlets, G the inlet
for air; H the outlet for the ozonised air.
Fig. 2 is an end elevation of an electrode with serrated strips or wires S. I may
arrange two pointed electrodes, one opposite to the other, or I may have two plain
electrodes, or one provided, and the other not provided with points. Part of the
end is removed shewing the cooling liquid inside; the inlet for the liquid is at the
bottom of the box and the outlet at the top.
Figure 2 is a side elevation of the box showing the serrated strips or wires S.
Figure 3 is a plan of the box with the lid removed, the positive electrode boxes
being marked P, and the negative electrode boxes being marked N. K are the
dielectric separators; E E the inlets for the cooling liquid; F F the outlets;
G the inlet for the air to be ozonised and H the outlet for the ozonised air.
There should be a space of about 4 millimetres between each active surface of
the electrodes and each side of the dielectric separator which must be parallel
with and equidistant from the electrodes at each side of it, and in order to keep
them accurately in position the dielectric separators may be provided at each
angle with a piece of glass or other insulating material constituting distance
pieces of a thickness corresponding to the space to be maintained. To attain
the same object the electrodes may be provided with distance pieces which may
be metallic.
Figure 4 shews an ozone generator with elongated box electrodes; (the pipes
for circulation of water are not shewn).
A is the inlet for the gas.

page_text: B is a chamber which may be conical or of any other shape, and over which is a
perforated false bottom C.
The inlet A is provided with a baffle plate, fan, or other distributor, not shewn,
to spread out evenly, the air which is forced through each of the slots of the false
bottom C (shewn in plan in Figure 5).
D is the space wherein the box electrodes are situated.
E is the chamber for the removal of the gas as soon as it has been ozonised and
passes from the narrow passages where it has been submitted to the action of the
effluvia. F is the outlet for the ozone.
The false bottom is so constructed that each space between two surfaces of
electrodes is just over each of these slits or apertures, through which the air is
forced in such a manner that it passes at any convenient speed between the
electrifying surfaces and cannot pass anywhere else.
Usually the inlet and the outlet of the ozonisers are two apertures of the same
diameter. I find it better to have a chamber E over the electrodes where the
ozonised gas is received more or less rapidly according to the requirements of the
operation; and an outlet F at a convenient spot of this chamber E, which outlet
is larger than the inlet A.
The distance between the electrodes varies according to the electric tension but
as a rule with a small transformer suitable for a one horse power ozoniser this
distance should be about eight millimetres.
The sets of electrodes are mechanically independent of each other and can be
readily and rapidly withdrawn from the receptacle when required for example, for
repairs or for inspection.
The electrodes are situated in such a manner that no space is left on their
ozonising surfaces which is not in contact with the air or oxygen or other gas forced
into the apparatus.
This electric action between every two active surfaces of electrodes would cause
a great development of heat in the very small space which separates them, but for
the circulation of cooling liquid, which from separate reservoirs passes through a
double system of piping one for the set of boxes connected to one pole of the
transformer, the other for the set of boxes connected to the other pole. Each set
of electrodes of opposite poles has therefore its own circulation of cooling liquid
and care should be taken to let the water flow separately from each set of electrodes
to avoid short circuits.
Figure 6 shews a set of electrode boxes connected together by pipes for the
feeding and circulating the cooling liquid which overflows through the pipe in the
upper part. Each set may consist of say 8, 12, 20, or more electrode boxes, and is
connected with one of the poles of the transformer or other source of current of
great tension and high frequency.
Figure 7 shews a similar set of boxes which are connected with the other pole
of the transformer or other source of electricity.
Figure 8 shews the two sets united and put together; and between each pair of
box electrodes is a dielectric separator which is not shewn in Figure 8.
As in a secondary battery, where the positive and negative electrodes are inserted
one between the others and where there is always one plate more in the cathode
set, there is one more box in one of the sets of the electrode boxes.
To place the electrode boxes together I have only to unscrew the unions of the
pipes and place the electrodes, Figure 6, between the electrodes Figure 7, and
when their unions and pipes are screwed, I separate them by means of the
dielectric.
In order to maintain a normal temperature, and therefore to secure a satisfactory
working of the apparatus and obtain the maximum yield of ozone, it is not however
sufficient to have a constant circulation, or from time to time a renewal of cooling
liquid.
The longer the air is in contact with the electrifying surface and the dielectric,
the warmer it is and the smaller the quantity of ozone formed. To obviate this

page_text: rise of temperature, which up to the present has been the unavoidable drawback in
the commercial production of ozone I withdraw the ozonised gas from contact with
the electrodes either by providing that the air moves with a sufficiently high
velocity or by the chamber E. When the ozonisers have to work continuously
during long periods I prefer to have the box electrodes long and narrow, so that
instead for instance, of 12 square electrodes 1 square foot which are plane or
provided with parallel rows of single or double serrated wires, soldered close to
each other on each side of the box, I may have 12 box electrodes 2 feet long and
only 6 inches wide. The total surface is the same, but the air or gas forced
through has to traverse a much shorter distance and therefore is not so hot after
having passed between two electrodes 6 inches wide, than if it had had to go
through a space of 12 inches.
It is advisable to use baffle plates or like devices to ensure that the air is made
to pass equally through the several ozonising spaces.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The construction of apparatus for the production of ozone substantially as
and for the purposes hereinbefore described and illustrated by the accompanying
drawings.
2. The use of hollow electrodes with cooling devices such as cold water
circulation in machines for the production of ozone substantially as described.
Dated this 21st day of July 1896.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.