Types of ozone generator
According to the way of ozone generation, there are three main types of ozone generators: one is high-pressure discharge type, the other is ultraviolet irradiation type, and the third is electrolytic type.
Type selection of ozone generator
1, the high-pressure discharge generator uses a high-frequency current of a certain frequency to create a high-voltage corona electric field, so that oxygen molecules in or around the electric field electrochemically react to produce ozone.
This ozone generator has the advantages of mature technology, stable operation, long service life, large ozone output (up to 1Kg / h in a single machine), etc., so it is the most widely used ozone generator in related industries at home and abroad.
Is divided into the following types in the high-pressure discharge ozone generator:
- According to the generator’s high-voltage electrical frequency, there are three kinds of power frequency (50-60Hz), intermediate frequency (400-1000Hz) and high frequency (> 1000Hz). Due to the shortcomings of large size and high power consumption, the power frequency generator has basically withdrawn from the market. Medium and high frequency generators have the advantages of small size, low power consumption and large ozone output, and are the most commonly used products now.
- According to the gas raw materials used, there are two types of oxygen and air. Oxygen type is usually supplied by oxygen cylinder or oxygen generator. The air type usually uses air (such as compressed air) as a raw material. Because ozone is generated by oxygen, and the content of oxygen in the air is only 21%, the ozone concentration produced by the air-type generator is relatively low, and nitrides are also derived. The oxygen purity of the bottled or oxygen generator is above 90%, so the ozone concentration of the oxygen generator is higher. When disinfecting the environment, an air generator is usually used. In water treatment, priority should be given to oxygen-type generators. But if the generator needs to be used with an old ozone mixing tower when disinfecting drinking water, only the air type can be used.
- According to the cooling method, there are water-cooled type and air-cooled type. A large amount of heat energy is generated when the ozone generator works, and it needs to be cooled, otherwise ozone will be decomposed while being generated due to high temperature. The water-cooled generator has good cooling effect, stable operation, no attenuation of ozone, and can work continuously for a long time, but the structure is complicated and the cost is slightly higher. The air-cooled cooling effect is not ideal, and ozone attenuation is obvious. Large generators or generators used in important locations are usually water-cooled. Air cooling is generally only used for generators with low ozone output or places where the performance requirements of the generator are not strict. When choosing generators, water-cooled ones should be used as much as possible.
- According to dielectric materials, there are several types of quartz tubes, ceramic plates, ceramic tubes, glass tubes and enamel tubes. Among them, quartz tubes are most commonly used by some high-performance ozone generators because of their high dielectric constant, uniform wall thickness, good ellipticity, high temperature resistance, and humidity resistance. The ceramic plate is brittle and only suitable for some small generators. The wall thickness and ellipticity of the ceramic tube are not easy to control, and the problem of uneven discharge is easy to occur, so it is not used much. Glass tubes and enamel tubes have a low dielectric constant, poor high temperature resistance, and are easy to burst. They are only used on some low-end generators.
- According to the structure of ozone generating components, there are two types of closed and open. The structural feature of the enclosed generator is that the sealing body itself is an electrode, and ozone can be used intensively, such as for water treatment. The electrode of the open generator is exposed in the air, and the generated ozone cannot be used intensively. It is usually only used for air purification in a small space or surface disinfection of some small items. The closed generator can be used instead of the open generator. The cost of a closed generator is much higher than that of an open generator. It is worth noting that some people now rigidly encapsulate the open generator to impersonate the closed generator. The result of this is that a large amount of heat cannot be dissipated in time, ozone attenuation is severe, and the generator is quickly burned.
2, the ultraviolet ozone generator uses a specific wavelength (185mm) of ultraviolet radiation to irradiate oxygen molecules to decompose the oxygen molecules to generate ozone. Due to the large volume of ultraviolet lamps, low ozone output, and short service life, this generator has a narrow range of use and is commonly used on disinfection cupboards.
3, lectrolytic generators usually produce ozone by electrolyzing purified water. This generator can produce high-concentration ozone water with low manufacturing cost and simple use and maintenance. However, due to its shortcomings, such as the ozone output cannot be increased, the electrode service life is short, and ozone is not easy to collect, its use range is limited. At present, this kind of generator is only used in some specific small equipment or in some specific places, and does not have the conditions to replace the high-pressure discharge generator.
In summary, the following factors should be given priority in selecting the ozone generator: medium and high frequency high voltage discharge type, quartz dielectric tube structure, water cooling, oxygen type, and closed type.