What is an ozone generator, and how does it work?

Ozone in one paragraph

Ozone (O₃) is a molecule of three oxygen atoms. The third atom is held loosely, which makes ozone a powerful oxidiser: it reacts with bacteria, viruses, fungi and many of the compounds behind colour, odour and taste, and then returns to ordinary oxygen.

How the generator makes it

Inside an ozone generator, oxygen passes through a high-voltage electrical discharge between electrodes, often called corona discharge. The discharge splits some oxygen molecules into single atoms, which join other oxygen molecules to form ozone.

Because ozone does not keep, it is always made on site, at the moment it is needed. Nothing has to be bought, transported or stored.

Feed gas: air or oxygen

The generator can be fed with dry, filtered air or with concentrated oxygen from an oxygen concentrator. Oxygen feed produces a higher ozone concentration. Dry, oil-free feed gas protects the electrodes and keeps output steady, which is why most Servo Ozone generators use oil-free compressors.

Getting ozone to work

Making ozone is half the job. It has to reach the water or air, stay in contact long enough, and any leftover gas has to be destroyed.

• Injection with a venturi injector or a diffuser
• Mixing with a static mixer and enough contact time
• Off-gas destruction with an ozone destructor

What to look for when you buy

Ask about the things that decide performance and running cost over years, not just the price on day one.

• Ozone output and concentration for your application, confirmed by testing where possible
• Electrode material and construction
• Clean, dry feed gas: oil-free compressor, filtration, oxygen option
• Control that holds output steady
• Service access, spares and local support