The Principle Of Operation And Installation Methods Of Ozone Generators.

An ozone generator is a device used to produce ozone gas (O3). Ozone is easily decomposed and cannot be stored, so it needs to be produced and used on-site (short-term storage is possible in special circumstances). Therefore, ozone generators are required wherever ozone is used. Ozone generators are widely used in drinking water treatment, wastewater treatment, industrial oxidation, food processing and preservation, pharmaceutical synthesis, and space sterilization. The ozone gas produced by the ozone generator can be used directly or mixed with liquids through a mixing device to participate in reactions.

I. Principles of Ozone Generators

1. Corona Discharge Ozone Generator Working Principle: Dry oxygen or oxygen-containing gas flows through a corona discharge zone composed of inner and outer electrodes. A high-frequency, high-voltage electrical energy of several thousand volts is applied to the discharge zone, ionizing the raw gas flowing into the discharge zone to generate ozone.

2. Electrolytic Ozone Generator Principle: Ozone is generated using the electrochemical oxidation of water. In water containing hydrated fluorescent anions, water can be oxidized to ozone at approximately room temperature with high current power.

II. Ozone Generator Circuit Diagram

The main parameters to be controlled in the ozone generation process are concentration and flow rate. Flow rate can be adjusted by adjusting the corresponding control valve, while ozone concentration is related to many factors, such as the gas source, power supply, generator structure, and cooling method. In this design, the working frequency of the ozone generator is mainly adjusted to control the ozone concentration.

While keeping the gas flow rate constant, adjusting the output frequency of the ozone generator's inverter power supply changes the working frequency, thus changing the high-voltage discharge power and achieving ozone concentration adjustment.

The ozone generator described in this article uses the dielectric barrier corona discharge method to generate ozone. It mainly consists of four parts: an air pretreatment system, a cooling system, a power supply, and a discharge chamber, and an ozone tail gas destruction system. The schematic diagram of the ozone generator discussed in this article is shown in the figure, where an air compressor compresses air into a gas purification and dehumidification device. The resulting dry and clean air is introduced into the ozone generation tube, and a high-voltage power supply powers the ozone generation tube, causing discharge between the electrodes, thus forming a certain concentration of ozone in the air flowing through the ozone generation tube. Because corona discharge causes an increase in the temperature of the electrodes and dielectric surface, thus accelerating ozone decomposition, the ozone generator tube must be cooled to control the operating temperature within a certain range.

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Early ozone generators used a direct step-up method at power frequency. The advantage of this method is its simple structure. However, because power frequency operation requires high voltage peaks to achieve the desired power induction, the insulation performance of the windings must be high, and the winding process is more difficult. Furthermore, power frequency operation results in large transformer size, unsatisfactory ripple and stability, and low ozone generation efficiency. Currently, the rapid development of power electronics and switching power supply technology has made high-frequency high-voltage power supplies a trend, reaching 50-100kHz, or even as high as 13.56MHz. Modern industrial ozone generators basically use medium-to-high frequency inverter power supplies, employing PWM and soft-switching technologies, with operating frequencies generally between 400-2000Hz, significantly improving the performance of the device and reducing its size.