01-06: Mixed-Oxidant Use in Cooling Tower Maintenance

Tests using mixed-oxidant solution instead of oxidizing biocides (chlorine or bromine) for cooling tower maintenance, and eliminating all other biocides, found: (l) aerobic bacteria countsconsistently less than l000/mL in cooling water (no colonies on the standard Easicult TTC dip slide test), a result rarely achieved using chlorine alone or chlorine with other biocides; (2) ease in maintaining Free Available Chlorine (FAC) concentrations at 0.2-0.3 mg/L; and (3) removal of biofilms from small areas of cooling surfaces where they had accumulated inthe previous maintenance program, and a consequent reduction or complete elimination of microbiologically-induced corrosion.