Water chlorination

Chlorination is the displacement of water with chlorine or chlorine compounds for the disinfection of drinking water, household sewage, water treatment in swimming pools or for bleaching.

Chemistry of chlorination

With the introduction of chlorine in water forms depending on the pH balance of chlorine, hypochlorous acid and hydrochloric acid.:

Depending on the pH, hypochlorous acid dissociates partially oxonium and hypochlorite ions:

In acidic solution are the main species Cl2 and HClO, while in alkaline solution mainly ClO is present, in addition to very small concentrations of ClO2 -, ClO3 -, ClO4 -.

Application

Chlorination of drinking water is used in water treatment disinfection, in which case, chlorine is added in the form of chlorine gas, chlorine dioxide or sodium hypochlorite. A preventive disinfection of drinking water, the so-called " protection - chlorination " is no longer permitted since the amendment of the drinking water regulations from 1 January 1991. As alternatives for disinfection of swimming pools or drinking water ozonation and the use of UV radiation are. In Germany, for the chlorination of water comprehensive accident prevention regulations.