:: Chlorine Dioxide Compared with other Major Disinfectants ::

CHLORINE DIOXIDE
The EPA comment ( personal communication, 2002 ) was that chlorine dioxide will become as important to the world in the next 20 years in the same way that chlorine was important for the last 100 years.
The level of visibility of chlorine dioxide has been immeasurably strengthened by its adoption by the EPA as the technology for the bioremediation of the various government and civilian buildings, which experienced the “anthrax letters “ attack in October 2001. Our one technology partner oxicat is the service provider to the EPA of chlorine dioxide technology.
The evolution of simple and cost effective chlorine dioxide generators has resulted in more countries and companies embracing this technology as an alternative to chlorine or to use it in combination with ozone and / or UV.
new generators are not hazardous to produce or apply
discharge problems have not surfaced because there are means of reducing chlorite to below aquatic toxicity levels
DBP of concern is largely chlorite but with the emergence of chlorite reduction technologies this problem is rapidly being reduced. Chlorate is a DBP but its MCL’s and toxicity levels are much lower ( considered non-toxic) in comparison to chlorite. [Chlorate is non toxic to Daphnia ].
Low to medium capital cost and running costs which can match gaseous chlorine levels.

COMBINED DISINFECTANTS
Combining disinfectants is done to overcome the disadvantages of the individual disinfectant:-
Chlorine Dioxide / Chloramines----- overcomes the nitrifying bacteria, maintains a strong residual throughout the distribution system as the final primary disinfectant. Levels are 0.5 ppm chlorine dioxide dose to the chloramines dose.

Chlorine / Chlorine Dioxide---- these two products set-up a recycling loop in that the free chlorine oxidises chlorite to chlorine dioxide and the chlorine dioxide keeps the free chlorine( hypochlorous acid HOCl) from dissociating.
The combination of chlorine dioxide and chlorine will have the following benefits:
Reduces THM and other chlorinated organics
Reduce chlorite levels in the final water.
Reduce the mutagenic properties of the final water
Reduce the impact on the environment
Improve the efficacy of the final disinfection treatment whilst making this combined disinfectant cost effective comparable to chlorine (gas) alone.

Typically the dosage is 3 parts chlorine dioxide to 2 parts chlorine.

Ozone or UV / Chlorine Dioxide---- the UV or Ozone produces the quick kill and the chlorine dioxide maintains a residual at lower dosages.