Oxidizing toxicants normally represent the backbone of a industrial water microbiological treatment program. The most cost-effective type of oxidant to use in any given application will vary based on a number of system parameters including: safety concerns, sophistication of feed equipment, pH of the water, contaminant level and type, economics and the current discharge restrictions under which the plant has to operate. This discussion will include the popular oxidizing technologies and highlight where they find the most widespread application.

• Chlorine
• Hypochlorites
• Solid Chlorine Donors
• Bromine
• Ozone

Many factors influence the selection of gaseous chlorine over chlorine-containing compounds or other oxidizing microbiocides, aside from basic considerations of comparative costs and the availability of materials. These include the volume of the industrial water system, characteristics of the recirculating water and treatment objectives. The effect of an extended oxidizing microbiocide program on the industrial tower structure should also be considered.