Thousands of water plants around the world have adopted the ozone disinfection method, which is a mature method. Compared with chlorinated disinfection, ozone has a stronger disinfection function. The deactivation of ozone is 10-100 times that of chlorine gas phase.

       There are still many unknown points about the inactivation mechanism of ozone on microorganisms. Some people think that ozone can completely oxidize the enzyme system and can act on substances in cells such as purines and pyrimidines in nucleic acids. Inactivation of bacteria by ozone first attacks the cell membrane, or inactivates bacteria through glycoproteins or glycolipids and certain amino acids; ozone can also act on the sulfur group of certain enzymes, destroy the activity of bacterial enzymes, and be oxidized by ozone Of bacteria have lost their ability to degrade sugars and produce gas. Some people also think that the inactivation of bacteria is caused by the destruction of cell walls, cell membranes, or the outflow of main components in the cells, resulting in a bactericidal effect.

       The mechanism of inactivation of viruses by some is that the primary part of ozone's effect on the virus is the outer shell of the virus, especially the proteins that form it, which prevents the virus from adsorbing the host bacteria. Another claim is that ozone damages nucleic acids.

In experiments, we learned that other ozone-depleting substances in water, such as iron, manganese, and organic matter, prevent ozone from inactivating bacteria. When organic matter and bacteria coexist, high-concentration organic matter tends to react with ozone before bacteria, and another part of the bacteria enters the inside of the organic micelle, is protected, and escapes the ozone attack. Therefore, the inactivation rate of E. coli is low.

         However, there are also weaknesses in ozone disinfection. Ozone is extremely unstable and easily decomposed. It cannot play a role in preventing secondary pollution in the water distribution network, and the cost of disinfection is high.