MONITORING OF CORROSION UNDER CATHODIC PROTECTION CONDITIONS UTILIZING COUPLED MULTIELECTRODE SENSORS
Real-time corrosion monitoring for carbon steel materials in simulated seawater under cathodic protection conditions was conducted, utilizing coupled multielectrode sensors. It was demonstrated that the coupled multielectrode sensor is an effective real-time tool for monitoring the effectiveness of cathodic protection and for measurement of the threshold value of the protection potential for specific equipment.
Studies of Microbiologically Influenced Corrosion Using a Coupled Multielectrode Array Sensor
A newly developed multielectrode array sensor (MASS) was used to conduct a series of abiotic and biotic tests to determine if the probe can detect corrosion induced by microbial activity. The probe was able to determine the maximum corrosion rate in the presence of sulfate reducing bacteria (SRB) and showed that this rate was at least a factor of 10 greater than in the absence of SRBs. In addition, the corrosion rates obtained using the probe were much higher than those determined using linear polarization resistance further demonstrating its inherent better sensitivity to localized corrosion.
Evaluation of Corrosion Inhibitors in Cooling Water Systems Using a Coupled Multi-Electrode Array Sensor
A multielectrode localized corrosion sensor has been developed for evaluating the performance of corrosion inhibitors for carbon steel in cooling water. Experimental results indicate that the coupled multielectrode sensor provided instantaneous measurement of corrosion currents and a rapid real-time response to the addition of inhibitors. Evaluation of several inhibitors showed that the sensor was able to distinguish between inhibitor type and concentration. It was also demonstrated that the sensor has a detection limit of 5x10-11A with respect to current measurement. The capabilities of the sensor may be suitable for online monitoring of corrosion in a variety of applications where real-time monitoring is required.