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.
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.