Disinfection with Chlorine Dioxide

ClO2 is a non-stable gas that cannot be stored neat and ClO2 must be produced at site in reaction vessel or Batch Tank, and used as demanded. ClO2 is a slightly soluble gas in water (0.3% maximum concentration). ClO2 solutions have a green colour (at higher conc. orange) and smell like a mixture of chlorine and ozone. ClO2 at usage concentrations can be stored for many days, without significant degradation. Reactor at 2% strength lasts 12 - 24 hours. Typical free residual concentration 0,3 - 0,5 ppm. For C.I.P. 2ppm is used. Avoid agitation, atomisation or heating to reduce “gassing-off” of vapours.

Chemistry and Properties Of ClO2

  • Oxidation rather than chlorination - Fast kill by destruction of cell membrane wall
  • No reaction with ammonia or ammonium compounds - good for refrigeration
  • Absence of Chlorinated Phenols and other by-products - (Bad TCP like taste)
  • Significant reduction in THM production (tri-halo-methane's), thought to be carcinogenic
  • Environmentally safe decomposition to sodium chloride and water
  • No reaction with water - true solution - independent of water pH value up to 12.0
  • ClO2 has a higher disinfection power (ORP, Redox Potential) than Chlorine

Graph of disinfection efficacy according to pH

Graph of disinfection efficacy according to pH

Disinfection Efficiency

Ozone > ClO2 > HOCl > OCl > Di chloramine > mono chloramine. Effective against all types of bacteria, fungi and algae being quoted as more sporicidal than chlorine. More effective at biofilm removal and penetration with a required concentration of 0.1 - 0.5 parts per million for potable approval. The quality of water for potable use including such parameters as aesthetic, chemical, microbiological, physical and health related aspects of water quality.

For further information about Disinfection with Chlorine Dioxide please call us on 01246 813110 or email info@advanced-water.co.uk - Alternatively you can complete our online enquiry form.