Chemistry: electrical and wave energy – Processes and products – Electrostatic field or electrical discharge
Patent
1991-12-24
1993-06-29
Niebling, John
Chemistry: electrical and wave energy
Processes and products
Electrostatic field or electrical discharge
2041575, 42218607, 42218608, C01B 1310, B01J 1908, B01J 1912
Patent
active
052231054
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
This invention concerns an ozone generator. In particular the invention concerns an improved ozone generator of the type which employs ultra-violet light irradiation of air.
BACKGROUND OF THE INVENTION
There are two common ways of generating ozone. The first employs an "ozinator discharge", and the second, safer method, employs ultra-violet irradiation of the air.
The "ozinator discharge" method involves applying a high voltage alternating current between two closely spaced parallel plate electrodes separated by a layer of insulation such as glass and an air space. The air space is filled with a diffused purple glow called an "ozinator discharge" if the electrode gap is not more than 2 mm to 3 mm. A high current flows and the formation of ozone is directly proportional to the power dissipated in the discharge at a given temperature. 85% to 95% of the electrical energy applied is dissipated as heat and the amount of power which can be applied is severely limited by cooling arrangements. Efficiency is adversely affected by moisture in the supplied air. Concentric tubular electrodes are preferred and corona or brush discharge is avoided as an inefficient way of generating ozone since, at the short air gaps involved, high voltages arcing would occur.
Ozone is also manufactured photochemically by the action of ultra-violet light of wavelengths shorter than about 2200 Angstrom.
Ultra-violet emitting fluorescent lamps are manufactured for this purpose, but although these lamps may nominally be rated to produce 30 grams of ozone per hour, it has been found impossible in practice to obtain more than about 6 grams per hour due to the inefficient operation of the lamp.
An object of the present invention is to provide an ozone generator which avoids or at least ameliorates disadvantages of the prior art.
DISCLOSURE OF THE INVENTION
According to one aspect the present invention consists in an ozone generator comprising an ultra-violet lamp;
means to direct a flow of an oxygen-containing gas through a zone at which the gas is exposed to ultraviolet radiation emitted from the lamp; and
means to pass the gas through a high voltage low current electric field prior to or during exposure to the ultra-violet radiation.
The oxygen-containing gas may, for example, be air or oxygen. The electric field is desirably applied between widely spaced apart (for example 1 meter apart) electrodes under conditions such that substantially no ozone is generated from the electric field alone when the lamp is not energized.
Surprisingly, it has been found that when air is irradiated by ultra-violet light from the lamp in the presence of the same electric field, the rate of ozone Production in preferred embodiments of the invention, is up to ten times greater than the rate of ozone production obtained from the lamp in the absence of the electric field. In preferred embodiments of the invention a plurality of sharpened rod electrodes is positioned at each end of a tube housing an elongate ultra-violet lamp. The plurality of electrodes at on tube end are of opposite polarity to the plurality of electrodes at the other tube end and are spaced apart by from 20 cm to 1 meter or more in distance. An alternating current having a peak potential difference exceeding 5000 volts and preferably 15000 volts is applied between them but current flow is small and no discharge is visible. Air at atmospheric pressure or slightly greater pressure is admitted at each end of the tube adjacent the electrodes, and a mixture of air and ozone exits from the tube at an outlet substantially equidistant from the tube ends.
According to a second aspect the invention consists in apparatus according to the first aspect wherein at least one magnet is associated with the lamp so that ionized particles within the lamp are influenced by a magnetic field to congregate in one or more localized regions whereby to concentrate the ultra-violet radiation emanating from the lamp in the zone through which the gas flows.
It has been found that substantial f
REFERENCES:
patent: 2637688 (1953-05-01), Ryan
patent: 3653185 (1972-04-01), Scott et al.
patent: 4131528 (1978-12-01), Tsujimoto et al.
patent: 4563286 (1986-01-01), Johnson et al.
patent: 4655933 (1987-04-01), Johnson et al.
patent: 4834948 (1989-05-01), Schmiga et al.
9 R. Kirk & D. Othmer, Encyclopedia of Chemical Technology 740-747 (2d edit.) (undated).
Arthurson Corporation Pty. Ltd.
Bolam Brian M.
Niebling John
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