Chlorine Dioxide

Chlorine Dioxide In Water Treatment

Chlorine dioxide is an extremely reactive gas, and because of its instability, cannot be stored. It must only be produced in the required quantities in special generators on the site where it is used.

Chlorine dioxide offers a number of advantages when compared with chlorine for water disinfection. Chlorine being the disinfectant mainly used. The disinfecting power of chlorine dioxide actually increases slightly with increasing pH, whereas with chlorine the disinfecting power reduces.

Chlorine dioxide remains stable in the pipeline system over a longer period and ensures microbiological protection of the water for many more hours, or even several days. Ammonia and ammonium, which cause significant chlorine depletion, are not attacked by chlorine dioxide, so chlorine dioxide is fully available for bactericidal action.

Chlorophenols, the compounds with intense odours, that are oftenproduced during water chlorination, are not formed when chlorine dioxide is used. Trihalomethanes (THMs), a group of substances, which, like their best known example, chloroform, (are suspected of being carcinogenic) are produced when chlorine reacts with natural water components (humic acids, fulvic acids, etc.). Measured THM concentrations, are drastically reduced, if present at all,when chlorine dioxide is used.

Advantages of chlorine dioxide:
Disinfection power is independent of pH.
High residual effect thanks to long-term stability in the pipeline system.
Reduction of the biofilm in pipelines and tanks, hence reliable protection of entire water systems against legionella contamination.
No reaction with ammonia or ammonium.
No formation of chorophenols and other intense odour compounds which can be produced in water chlorination.
No formation of THMs and other chlorinated hydrocarbons, no increase in the AOX value.