Cathodic Protection of Hot Water Tanks at Fort Sill

Abstract : This corrosion prevention and control project demonstrated the use of ceramic anodes for impressed current cathodic protection (ICCP) systems for retrofitting in six large 1,000 to 3,500 gallon hot water storage tanks that service barracks and adjoining mess halls at Fort Sill, OK. The cathodic protection systems were designed to provide corrosion protection to the bare steel interior of the tanks that are susceptible to corrosion. This is a first time installation of horizontal anode in large hot water storage tank ASME Pressure Vessel with no man-ways. These cathodic protection systems have continued to operate as designed since their initial operation in April 2006 and have provided complete corrosion control since their original installation. The lifetimes of these large tanks are expected to be extended 30 years as a result of installing the ICCP systems using ceramic coated (mixed metal oxide) anodes. In addition, 17 smaller hot water tanks and hot water heaters (37 to 1,000 gal) were replaced with new hot water tanks and hot water heaters with factory-installed sacrificial anodes and glass linings. For the smaller tanks, it is more economical to use glass linings and sacrificial anodes than ICCP systems.