How does ozone disinfection work?



Ozone disinfection works through oxidation.


Molecular oxidation is used in low pH conditions and hydroxyl oxidation in high pH media.


Chlorine disinfection is a slow process where chlorine spreads through the cell walls and invades the enzyme. This works differently with ozone: the cell membranes are destroyed or broken down, then the ozone is inactivated, changing from O3 to O2. This process is very fast.


All you generally need is to apply a 0.1 mg/l dose of ozone for 5 seconds, compared to 4 hours for chlorine. It has also been shown that a large number of microorganisms can be killed in just 4 minutes just 0.2 ppm of ozone. Ozone can also eliminate 99% of 60,000 coliforms/ml in contaminated water in 2.8 seconds with a dose of 0.8 ppm (the same dose of chlorine would take 15,000 seconds).

That’s how it works…



Ozone breaks down the microorganism’s cell wall to create a hole, through which it loses its cellular fluid. Disinfection using ozone is called bacteriolysis. The elimination of microorganisms with ozone does not produce resistance because its mechanism of action is based on rupturing the cell wall.


Aerobic spore-forming bacteria are more easily disinfected than anaerobic spore-forming bacteria. The effectiveness of disinfection in a solution is strongest against lactic acid bacteria, and therefore also against fungal yeast.


The effectiveness of disinfection is influenced by contact time, ozone concentration, water temperature, pH level and the dissolved organic and inorganic substances.