history

Chlorine dioxide’s use for potable water disinfection dates back to 1944 and has since been widely accepted as a versatile, effective, and more environmentally friendly disinfecting alternative for various large-scale commercial applications. Pre- and post-oxidation chlorine dioxide disinfection helps to produce clean water with low turbidity, a standard measurement for water quality, through pre-oxidation treatment to remove algae, bacteria, etc. and post-oxidation treatment to remove inorganic components, like manganese and iron, pathogens (including chlorine-resistant pathogens), like Giardia and Cryptosporidium, and to reduce and prevent the production of trihalomethanes (THMs) and haloacetic acids (HAA) that are not safe for consumption. It also functions as a water deodorizer and taste remover with a residual effect, meaning that, where other disinfectants like Ozone allow for the regrowth of bacteria and biofilm once it self-decomposes, chlorine dioxide remains active and, therefore, in effect, for longer periods of time.

Because only a small dose of chlorine dioxide is necessary for effective potable water treatment, fewer by-products are produced. Chlorine dioxide decomposes into chloride—a human safe ion such as that in table salt. Its other DBPs (disinfection byproducts), chlorite and chlorate, are typically monitored for safety levels.

chlorine vs chlorine dioxide (typically in water treatment)

Chlorine

Advantages

  • Effective for most microorganisms
  • Keeps a residual in distribution system
  • Relatively easy to use in hypochlorite form

Disadvantages

  • Forms DBPs when organic substances are present
  • Not effective against Cryptosporidium
  • Can cause taste and odor problems

vs

Chlorine dioxide

Advantages

  • More effective than chlorine as a disinfectant against microorganisms
  • Controls taste and odor better than chlorine
  • Forms less THMs and HAAs than chlorine

Disadvantages

  • Traditionally must be produced on site
  • Forms chlorite and chlorate

View the other industrial applications of chlorine dioxide

Water Treatment (currently viewing)

Food Processing

Disinfection of Airports

Agriculture

Industrial Facilities

Healthcare

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