Siemens’ Chlorine Dioxide Generators Help Communities Meet Disinfection Byproducts Rule

June 21, 2006

The Millennium III series generators from Water Technologies, a division of the Siemens Group Industrial Solutions and Services (I&S), boasts high performance with durability, simplicity of use and easy maintenance, as well as compliance with the U.S. EPA’s Stage 2 Microbials/Disinfection Byproducts (M/DBP) cluster of rules.

The Millennium generators combine a 25% sodium chlorite solution with chlorine gas (or 12.5% sodium hypochlorite and 15% hydrochloric acid to form chlorine in-situ) under vacuum conditions to generate chlorine dioxide safely and efficiently. The generators are capable of consistently producing onsite chlorine dioxide with a yield efficiency of 95%. Efficiency and yield are maximized by reaction of chemical reactants in their concentrated form. These reaction conditions favor the immediate formation of chlorine dioxide and therefore minimize byproduct formation found in other types of generators.

Recognized by the EPA as a primary disinfectant, chlorine dioxide is a powerful disinfectant and oxidizing agent. Chlorine dioxide has proven economical and effective when treating waters high in ammonia, manganese or organic content and in destroying phenol-based taste and odor-causing compounds. It is effective in controlling a broad spectrum of viruses, bacteria and protozoa like Giardia and Cryptosporidium. Chlorine dioxide does not form trihalomethanes (THMs), trihaloacetic acids (THAAs) or other chlorinated organic compounds, nor will it react with many impurities that normally consume chlorine.

As it is essentially unaffected by pH, onsite chlorine dioxide generation is a cost-effective means of treating waters high in pH. Chlorine dioxide is also very effective in controlling biofilms, preventing nitrification and extending the life of chloramines in the distribution system. Furthermore, it does not oxidize bromide to bromate, and can be a valuable aid in providing CT credits and in serving as a pre-oxidant applied to raw water to reduce the demand on downstream ozone dosages.

Source: Siemens Water Technologies