A new on-line monitoring system has been developed for pitting corrosion monitoring of carbon steel tubes in cooling water systems. This monitoring system was found to be quite sensitive to microbiological activity relating to pitting corrosion on a real-time basis. The value of galvanic current indicates the performance level of pitting corrosion inhibition even in hiocide application. In addition the changes in the galvanic current provide indicative information about the effectiveness in microbiological control program, even when the
pressure drop measurement indicates no biofilm formation. It can be also useful in detecting a microbiological control upset. In this paper, an introduction of the new monitoring system as a microbiological control effectivenew monitor and the field test results are discussed.
Keywords: monitoring, pitting corrosion localized corrosion biocide effectiveness cooling water, carbon steel, on-line measurement, microbiological control, heat exchanger