Ozone generation is the process of producing ozone (O₃), a molecule made of three oxygen atoms, which is used for disinfection, oxidation and sanitisation of air and water. In this article we’ll explore what ozone generation is, how it works, and how companies like Wassertec Ozone Systems (based in Cape Town, South Africa) design equipment to put this into practice.

What is ozone (O₃)?

Ozone is a molecule composed of three oxygen atoms. Unlike the O₂ we breathe, O₃ is less stable and highly reactive.

Because of its extra atom, ozone has strong oxidising power — meaning it readily reacts with other substances (microorganisms, organic contaminants, odours) and changes them chemically.

Ozone (O₃) is made by splitting an Oxygen (O₂) molecule and re-combining the atoms as an odd number.

There are two common methods to do this:

High voltage discharge (corona discharge) — “think of it as making lightning in a box.”

Ultra violet (UV) light at a specific frequency.

So essentially ozone is “activated” oxygen used for sanitisation and treatment.

Why use ozone generation?

There are several advantages to using ozone rather than traditional chemical treatments:

Powerful disinfection: Ozone is an excellent disinfectant with the superior ability to kill viruses and biological contaminants found in water.

No chemical residue: After doing its work, ozone reverts to oxygen, leaving no chemical residue behind.

Improves taste & odour: Especially in water treatment, ozone oxidises metals like iron, manganese, sulphur, and organic compounds that cause odour or taste problems.

Environmentally friendly/sustainable: Ozone is a safer, greener alternative to chemical sanitation” as it avoids chemical usage, leaves no by-products and supports eco-goals.

Versatility: Ozone generation applies to both water treatment (drinking water, industrial water) and air/surface sanitation (odour removal, hotel rooms, waste areas).

Because of these benefits, ozone systems are increasingly used in bottled water plants, cooling towers, air treatment, and more.

How does ozone generation work?

Here’s a breakdown of how ozone is produced and applied:

1. Generation of ozone

The first step is generating ozone from oxygen or ambient air. Two main generation methods are:

Corona Discharge (CD) method: An electric discharge splits O₂ molecules into single oxygen atoms (O). These then combine with O₂ to form O₃. This is the dominant method for water treatment systems.

Ultra Violet (UV) method: UV light at a specific wavelength splits O₂ molecules, forming ozone. More commonly used for air treatment/odour removal.

For example, Wassertec’s “Azure” model is described as a corona discharge generator for continuous water treatment:

2. Feeding the generator with suitable gas

Some systems use ambient air (normal atmospheric air).

Others use oxygen-enriched gas (higher purity O₂) to produce ozone more efficiently. For example, Wassertec’s oxygen concentrator (“OX-5”) supplies >93 % O₂ from compressed air for better performance.

The quality (dryness, purity) of the feed gas matters. For instance, the Azure specs list different outputs based on air vs oxygen feed.

3. Mixing ozone with the medium (water or air)

Once ozone is generated, it must be introduced into the water or air to achieve treatment. Here are two scenarios:

Water treatment

The system uses a pump and usually a venturi injector or diffuser to draw ozone gas into the water stream. For domestic systems the pump circulates water in the tank through the venturi … the venturi creates a vacuum which draws ozone into the water. Ozone disinfects and decontaminates the water.

The ozone reacts with contaminants: the extra oxygen atom oxidises bacteria, viruses, organic matter, metals, etc. The contaminated molecules get transformed (oxidised) and can then be filtered or removed.

Because ozone leaves no residue (it reverts to oxygen), the treated water is “clean” without added chemicals.

Air / odour treatment

For air treatment, the ozone generator injects ozone into the space. Wassertec’s UVO unit (UV ozone generator) is used for indoor environments: “Ozone air treatment … is a safe, simple and effective way of eliminating odours and sanitising any indoor environment.”

For example, treating a hotel room: a 200 mg/hr unit can treat a 35 m² room in ~20-30 minutes.

4. Reaction and destruction of contaminants

Once ozone is in the medium:

In water: O₃ oxidises organic compounds (viruses, bacteria, algal material) and inorganic (metals like iron, manganese, sulphur) turning them into insoluble particles or harmless molecules. E.g., “Ozone is an excellent disinfectant … It is also a very powerful oxidant that can oxidize metals … aiding in their filtration and removal from water.”

In air: Ozone oxidises odorous compounds, mold, airborne pathogens, etc. This breaks them down and neutralises odours.

After reaction, ozone decomposes back into oxygen (O₂). It leaves no chemical footprint.

5. Considerations and safety

While ozone is highly effective, it must be used correctly. At high concentrations ozone can be harmful to humans. In low concentrations (< 0.2 ppm) ozone is not harmful. In high concentrations, ozone can be very harmful.

The feed gas, generator design, contact time, dissolution, and mixing impact how effective ozone treatment is. Ozone is more challenging to produce and deliver than chlorine … About 85 % of the energy input to a corona discharge system is wasted in the form of heat.

As no residual disinfectant remains (unlike chlorine), systems must be designed to ensure the ozone does its work while the medium is in contact. Operators must monitor and design for residual ozone, contact time, flow rate.

For water with high bromide content, ozone can form bromate – a potential carcinogen – so caution is required.

Real-world applications: How Wassertec implements ozone generation

Here are some practical examples of how ozone generation is implemented:

Bottled water / beverage industry

Wassertec’s “Bright Blue CCS Ozone Systems” are designed specifically for prepared-water disinfection in the bottled-water industry. These systems meet high standards (e.g., 4 min contact time, ~0.5 ppm residual ozone for a 5-log reduction in microbiology, per Coca-Cola specification).

Ozone improves taste & odour, extends shelf life, and offers chemical-free treatment of bottles/water.

Air / odour treatment

The UVO model (UV ozone generator) is used for indoor odour removal and air sanitation. Example: hotel rooms, smoking areas, cold storage rooms. A 200 mg/hr unit is quoted for a ~35 m² room in 20-30 mins.

Domestic & light commercial water treatment

An “Azure” corona discharge generator can be used in a home tank (up to ~10,000 litres). A pump circulates the water, a venturi draws ozone in, the water is then filtered and used.

Oxygen concentrators supporting ozone generation

Oxygen supply is critical: The OX-5 oxygen concentrator produces up to 5 L/min of >93% purity oxygen from compressed air. This clean oxygen feed helps a corona discharge ozone generator produce ozone more efficiently.

Step-by-step: Typical ozone generation system for water

Here is how one might set up an ozone generation system for water treatment:

Feed gas preparation: Ambient air is dried and filtered, or high-purity oxygen is supplied (via an oxygen concentrator like OX-5) to the ozone generator.

Ozone generator (Corona Discharge type): The generator applies a high voltage to the feed gas, creating ozone (O₃) from O₂. Example: Azure or Indigo systems from Wassertec.

Injection into water: A pump circulates water from the tank; a venturi injector or diffuser draws ozone into the water stream, mixing it thoroughly. (The pump circulates water … the venturi creates a vacuum which draws ozone into the water.)

Contact time: The water remains in contact with dissolved ozone for enough time to oxidise and destroy contaminants (microorganisms, organic/inorganic).

Post-treatment: After oxidation, insoluble particles (e.g., oxidised metals) may be filtered out. The water may then proceed to use or bottling. Because ozone reverts to oxygen, no chemical residues remain.

Monitoring & safety: Ozone concentrations, contact time, ORP (oxidation reduction potential) may be monitored; ventilation and ozone detectors ensure safe operation (these are built into our systems).

Key takeaways for installation and design

Ensure proper generator type: For water treatment, corona discharge is preferred; for air/odour, UV type may suffice.

Pay attention to feed gas quality: Using purified oxygen improves ozone output; ambient air may suffice for lower capacity applications but with lower ozone yield.

Ensure good mixing/contact time: Ozone must be dissolved and maintained in the medium long enough to act. Poor mixing or short contact time reduces effectiveness.

Provide appropriate safety controls: Ozone is a strong oxidant and at high levels is harmful. Proper detectors, ventilation, safe design are essential.

Understand application specificities: For example, in bottled water the system is designed for high throughput, specific residual target, and integration with filling lines. In domestic systems, simpler setups suffice.

Consider maintenance and lifespan: Ozone generators, especially at industrial scale, require maintenance (cleaning electrodes, ensuring dry feed gas etc). Our quality philosophy emphasises durability and serviceability.

Conclusion

Ozone generation is a sophisticated and highly effective technology for disinfection and oxidation in both water and air. It leverages the unique chemistry of O₃ to destroy contaminants, improve taste/odour, and minimise chemical residues. Wassertec Ozone Systems has built systems tailored to various applications (industrial bottling, water treatment, air odour control) using high-quality components and strong safety/quality practices.

If you’re considering ozone generation for your facility, it’s vital to align generator type, feed gas quality, injection/mixing design, safety controls and application requirements. With the right setup, ozone offers a greener, powerful alternative to many chemical treatments.

 

Click here for more information – Wassertec – Specialists in ozone systems and ozone technology.