F-1 The Effect of Corrosion Inhibitors on the Fouling Characteristics of Cooling Tower Water

J. G. Knudsen, E. Santoso, and J. M. Chenoweth

Corrosion inhibitors are often added to cooling tower water to prevent the corrosion of the various metallic elements of the cooling water system. These are effective in preventing corrosion; however, they can, under some circumstances, be the source of fouling in the heat exchangers. This report describes a three-year experimental study conducted at Oregon State University for HTRI during which the significant parameters--type of corrosion inhibitor additive, system pH, surface temperature, and velocity-- were systematically varied and their effect on fouling determined. A total of 185 individual long-term tests is reported. It was shown that the fouling material evolved from the corrosion inhibitor additives and that its extent and rate can be controlled to acceptable limits.