Evaluation of Alkaline and Enriched Dissolved Oxygen Operating Condition of Generator Inner Cooling Water System of Unit 3 in a Power Plant

A bypass for corrosion rate measurement of copper electrode was installed in generator inner cooling water system of unit 3 in a power plant and its real corrosion rates were obtained by electrochemical method. Through tests of changing the dissolved oxygen content in inner cooling water, its influence on the corrosion rate was also investigated. Results showed that enriched dissolved oxygen operating condition could provide excellent protection for corrosion of copper bars but transformating to other conditions should be avoided because of the increasing risk of dissolving and peeling off of corrosion products. Monitoring the dissolved oxygen content in inner cooling water and sustaining the system operating in enriched dissolved oxygen condition were suggested.