Significant observations from a PWR steam generator chemical cleaning qualification test program

A qualification test program for the chemical cleaning of the secondary side of steam generators was conducted in anticipation of a potential application at Indian Point 2 (IP-2). The sludge removal effectiveness was evaluated using a large-scale test facility and both simulated consolidated sludge samples and sludge removed from IP-2 steam generators during prior sludge lancing. The test also mocked up the weld geometries and locations for an accurate galvanic corrosion assessment. This large-scale test and other preliminary tests had the following three aims: (1) optimize and demonstrate the sludge removal effectiveness of the Electric Power Research Institute/Steam Generator Owners Group (EPRI/SGOG) generic cleaning process for the Westinghouse Model 44 steam generators, (2) determine the corrosion effects of the process on Westinghouse Model 44 steam generator materials that would be exposed to the process, and (3) identify technical issues that should be addressed prior to field implementation of the process. The qualification test program also included the evaluation of an eddy current technique that measures sludge height in the presence of copper (IP-2 sludge contains more than 30 percent copper)