George J. Licina

Stress Corrosion Cracking of Steam Turbine Rotors

Abstract In the wake of the catastrophic failure of a low-pressure (LP) turbine disk at the Hinkley Point Nuclear Station in 1969, considerable research and development has been devoted to the prob...

Monitoring Biofilm Formation in Power Plant Environments

Power plants have experienced severe general corrosion, pitting, under deposit corrosion, and microbiologically influenced corrosion (MIC) in cooling water systems, resulting in decreased plant availability and significantly increased operations and maintenance costs. MIC has been a particularly difficult problem since corrosion resistant alloys in relatively benign environments have failed as a result of microbiological influences in short times. Copper base alloys, carbon steels and stainless steels have all been susceptible. In a number of instances, replacement of piping and heat exchangers has been required to alleviate corrosion-related problems. Monitoring is a key element to improved corrosion control in cooling water systems. On-line methods provide evaluations of corrosion rates in real time and are sensitive to localized corrosion. Electrochemical methods of corrosion measurement are readily automated, both for acquisition of corrosion data and for process control. An electrochemical probe for on-line monitoring of biofilm activity has been shown to provide an early warning of biofilm formation and incipient MIC in fresh and saline waters.