Field Evaluation of Cathodic Protection Systems Using Ceramic-Coated Anodes forLock and Dam Gates

摘要

Since 1950, the Army Corps of Engineers has used impressed current cathodicprotection (CP) systems, using either graphite or high silicon chromium bearing cast iron (HSCBCI) anodes with protective coatings. Both systems help control corrosion of hydraulic structures immersed in either fresh or salt waters, and hybrid CP systems can contain both types of anodes. Research continues in the search for better and more economical materials. This study documented the use and evaluated the field performance of impressed current CP systems using ceramic-coated anodes made of a new material (titanium-based iridium oxide), for miter, sector, and tainter gate applications Army Civil Works (water resource) projects. A cost analysis including materials, installation, and power assumption was done, and the new system was compared to conventional HSCBCI anode systems. CP systems using iridium oxide ceramic anodes for lock and dam gates were found to be an effective alternative to HSCBCI anode systems. The estimated annual power cost and the total materials and installation costs of the two systems were estimated to be approximately equal. At high-coating efficiencies, the HSCBCI anodes were slightly more efficient (1.6 percent), but at all other coating conditions, the ceramic anode is more efficient. (MM).