RU2358897C2 - Device for ozonising air - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: proposed device contains a comb-type discharge electrode with closely spaced spikes and a plate electrode, separated by dielectric barriers arranged into an H-shape and an air gap. The coronating spikes have a cross section which narrows down to zero at the tips and have several sharp longitudinal edges. They are situated at the tops of squares tops of side 5-7.5 mm and they are fitted in holes on a carrying plate and their heads are fixed by hardening putty (paste) based on graphite.

EFFECT: protection of a joint from aggressive effect of ozone.

2 dwg

Description

A device for ozonation of air relates to electrical engineering, in particular to devices for ozonation of air, water, etc.

A device for disinfecting air with ozone is known, consisting of an external cylindrical electrode made of a metal mesh and an internal electrode containing discharge disks and star-shaped ionizing disks of different diameters (USSR Author's Certificate No. 1465412, MPK7 С01В 13/10, 1989). The disadvantage of this device is the complexity of the design and change of the corona elements (stars), subject to intense erosion of the metal in the corona discharge, which occurs at a high voltage power source (from 15 to 40 kV).

Also known is the ozonizer used in the technological process of egg incubation (USSR Author's Certificate No. 1192755, MPK7 А01К 41/00, 1985). In this device, the corona electrode uses needles of complex shape with pointed protrusions on the side surfaces. The contribution of the pointed protrusions to the generation of ozone in comparison with the contribution of the tip of the needle is insignificant, since the maximum electric field strength is observed towards the second electrode. In order for the contribution of the pointed protrusions to become significant, it is necessary to use a high voltage (up to 40 kV). Each needle has 6 pointed protrusions on its lateral surface. And the corona discharge current density is only 1.64 times higher than that of electrodes with needles without protrusions (ozone generation is directly proportional to the corona discharge current). The presence of a high voltage source (40 kV) dramatically narrows the scope of use of ozonizers of this design in terms of the safety of their maintenance and the compactness of the device.

The closest in technical essence is a device for ozonation of air, the corona electrode of which is a lattice, in the nodes of which are conductive needles facing the smooth surface of the second electrode (USSR Author's Certificate No. 1141486, IPC7 H01T 23/00, 1985 (prototype)). The alternation of the polarity of the grids with fixed needles complicates the design of the supporting insulation of the corona electrodes and the entire device as a whole. Moreover, with a lattice design of the electrodes, a denser arrangement of needles is practically not feasible.

The purpose of the invention is to achieve compact design and improve the operational characteristics of the ozonizer.

The goal is achieved as follows. The use of glass dielectric barriers and the developed total length of sharp edges on the lateral surfaces of the needles make a 5 kV power supply sufficient to obtain the desired level of ozone formation. At this voltage, the formation of nitrogen oxides does not occur. The ozone emission of the device is determined by the magnitude of the corona discharge current, which depends on the number of needles in the corona electrode. A tangible mutual screening of the needles is observed at distances between them less than 5 mm, therefore, for the greatest compactness of the device, the distance between the tips is made equal to 5-7.5 mm. The corona discharge current flowing from the needles in the direction of the second electrode, which is covered by a dielectric, with an air gap of 0 to 6 mm, is 0.2 and 0.18 mA, respectively, with 20 needles per row 100 mm long. Such an ozonizer device allows the use of needles with some variation in their length. The needles are fastened in the holes of the carrier plate and fixed by means of graphite-based putty. This allows the use of carrier plates with a thickness of 1-2 mm and provides parallel needles even with a vertical arrangement of the carrier plate. With this design, the removal and replacement of needles is facilitated if necessary.

The use of graphite-based paste for fixing the needle heads on the supporting plate of the corona electrode simultaneously protects the joints from the aggressive effects of ozone, therefore, a special protective surface coating is not required. This is especially important for ozonizers with round-the-clock operation.

Figure 1 shows the device of the ozonizer.

The device contains a corona electrode (“comb”) 1 and a flat electrode 2 with glass dielectric barriers 3. Electrodes 1 and 2 are attached to the casing 4 of the ozonizer using supporting porcelain insulators 5. A high-voltage source (5 kV) 6 of industrial frequency is located outside. In the ozonizer casing there are several holes for the passage of air (not specified). The holes are located at the safest distance from ozonizer parts that are under high voltage. The ozonizer casing is grounded. Bolted joints 7 allow you to adjust the magnitude of the interelectrode air gap.

In FIG. 2 shows a fragment of the corona electrode 1.

The supporting plate 8 of the corona electrode has openings equally spaced from each other in which the needles 9 with sharp longitudinal edges are attached. The needle heads are fixed relative to the carrier plate using a hardening layer of putty paste 10 based on graphite. Between the walls of the casing of the ozonizer and the ends of the glass barrier are located H-shaped placed additional glass barriers, which are designed to increase the path of leakage currents.

The device operates as follows. When applying a high voltage to the electrodes on the needle tips and their sharp longitudinal edges, a high intensity of a sharply inhomogeneous electric field is created. As a result of this, a corona discharge occurs, accompanied by ozone release. Ozone, due to its higher density, leaves the casing and mixes with the outside air. A sparkless discharge and a sparing 5 kV power supply voltage exclude the formation of nitrogen oxides.

The tight placement of needles contributes to the compactness of the device. Given the mass of porcelain insulators and a high voltage source, the mass of the ozonizer is about 20 kg. The power consumption of the ozonizer is 50 W, its productivity is up to 30 g of ozone per hour and can be increased due to a larger number of needles.

According to the information available to the authors, the set of essential features that guarantee the essence of the claimed invention is not known and for specialists it should not be obvious from the prior art; which allows us to conclude that the invention meets the criteria of “novelty” and “inventive step”.

Claims (1)

A device for ozonation of air containing a corona electrode - a comb with closely spaced needles and a plate electrode separated by H-shaped dielectric barriers and an air gap, characterized in that the corona needles are attached to the holes of the carrier plate of the comb electrode, and their heads are fixed hardening putty (paste) based on graphite.

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