Electrochemical techniques for monitoring and controlling corrosion in water-cooled nuclear reactor systems

This chapter reviews the use of electrochemical methods for exploring the properties of, and the corrosion of metals and alloys in, high temperature aqueous systems that are used as coolants in thermal power plants, including water-cooled nuclear reactors. The review discusses the use of high temperature aqueous systems as reactor coolants, and then defines some of the important properties of both subcritical (. T < 374.15°C) and supercritical (. T > 374.15°C) systems. Various sensors for monitoring the properties of both subcritical and supercritical systems are briefly discussed with emphasis on electrochemical techniques. These sensors have proven to be remarkably accurate in monitoring pH, redox potential, corrosion potential, the concentrations of dissolved oxygen and hydrogen, and the monitoring of corrosion rate. The chapter ends with a brief discussion of the use of electrochemical techniques and principles for controlling corrosion phenomena in operating nuclear reactors.