Ozone is a powerful disinfectant used in water purification. It kills bacteria, viruses, and other harmful microorganisms by breaking down their cell walls. Unlike chlorine, ozone works quickly and leaves no chemical residue in the water.

When ozone is introduced into water, it reacts immediately with pollutants. This reaction destroys pathogens and neutralizes chemicals that cause bad taste or odor. Many water treatment plants prefer ozone because it improves water quality safely and effectively.

Ozone also helps remove iron, manganese, and sulfur compounds. These compounds can cause staining and unpleasant smells. By oxidizing them, ozone converts these compounds into solid particles, which can be filtered out easily.

In addition, ozone is eco-friendly. It breaks down into oxygen, leaving no harmful byproducts behind. This makes it a safe choice for drinking water and industrial processes.

Benefits of Using Ozone for Water Purification:

• Rapid disinfection of bacteria and viruses
• Removes unpleasant odors and tastes
• Oxidizes harmful metals and chemicals
• Leaves no chemical residue
• Eco-friendly and safe for humans

By using ozone as a disinfectant, water becomes cleaner, safer, and more pleasant to drink. Its efficiency and safety make it a top choice for modern water purification systems.

What Is Ozone and How Is It Produced?

Ozone (O₃) is a molecule composed of three oxygen atoms. It differs from the common oxygen gas (O₂) in that it carries an extra oxygen atom, which gives it extreme oxidative power. This characteristic makes ozone very effective at breaking down contaminants.Puritech

Ozone cannot be stored or transported because it is highly reactive. Instead, it must be generated on‑site using specialised ozone generators that apply an electrical discharge to oxygen or air to create ozone gas.

How Ozone Disinfects Water

• Diffusion Into Water

  • When ozone is introduced into water, it dissolves and begins interacting with the dissolved substances and microorganisms present. Ozone’s relatively high solubility in water helps it spread efficiently throughout the treatment zone.

• Oxidation of Microbial Cell Structures

  • Ozone is one of the strongest oxidants used in water treatment. When it contacts bacterial cell membranes, it reacts with the lipid and protein components, disrupting the membrane’s integrity. This disruption leads to leakage of cell contents and ultimately to cell lysis — in other words, the microorganism is destroyed. Puritech
  • Once ozone enters a microbial cell, it continues to oxidise internal components such as proteins, enzymes, and nucleic acids (DNA and RNA), further ensuring the microorganism cannot survive.

• Inactivation of Viruses

  • Viruses, which lack typical cellular structures, are similarly vulnerable to ozone. Ozone molecules oxidise the viral protein coat and interfere with the nucleic acids inside the virus. This prevents the virus from attaching to and infecting host cells.

Advantages of Ozone Disinfection

• Broad‑Spectrum Efficacy

  • Ozone works rapidly against a long list of pathogens, including bacteria, viruses, protozoa, and resistant species such as Giardia and Cryptosporidium, which are less susceptible to some other disinfectants.Puritech

• Fast Action and No Harmful Residues

  • Ozone acts quickly — often within minutes — and breaks down into oxygen shortly after disinfection. This means it leaves no toxic residues or disinfection by‑products (DBPs) like trihalomethanes (THMs) and haloacetic acids (HAAs), which can form with chlorine treatment.

Because ozone ultimately reverts to oxygen, it is environmentally friendly and reduces the risk of harmful chemicals in treated water.

Beyond Disinfection: Contaminant Oxidation

In addition to its disinfectant role, ozone also oxidises other water contaminants. These include iron, manganese, sulfides, and various organic compounds that cause taste, odour, and colour problems in untreated water. The oxidative reactions make these substances easier to remove through subsequent filtration stages.

Considerations and Limitations

Despite its many benefits, ozone has limitations. Because it is highly reactive, ozone has a short half‑life in water and does not provide long‑term residual disinfection in distribution systems. This is why some water treatment facilities may still rely on additional disinfectants like chlorine to maintain safety over long pipelines.

Additionally, ozone generation requires specialised equipment and precise control of contact time, pH, and water chemistry to ensure optimal performance.H2oCareerPro

Conclusion

Ozone’s powerful oxidative properties make it one of the most effective disinfectants available for water purification. It disrupts microbial cells, inactivates viruses, and oxidises a wide range of contaminants, all while leaving no harmful chemical residues behind. Although ozone requires on‑site generation and careful handling, its rapid action and broad‑spectrum efficacy make it a valuable tool in modern water treatment systems.