Water disinfection: water disinfection is needed for patogenic microorganisms (bacteria, incl. iron and sulfur bacteria, viruses), parasites (Giardia lamblia, Cryptosporidium etc.) and algae inactivation during drinking water production. Disinfection is also one of the posttreatment stages of wastewater. As disinfectants chlorine (Cl2), sodium hypochlorite (NaOCl) and chlorine dioxide (ClO2) have been used. The strongest oxidant is ozone which is even able to destroy HIV and Polio viruses in water.
