The Effect of the CAN-OECON Decontamination Process on the Surface Oxides on Pickering Units 1 and 2 Feeder Pipes

Abstract

The oxides on sections of feeder pipes from Pickering Units 1 and 2 were examined. The reactor inlet feeder oxide was found to be thicker than the outlet feeder oxide, indicating that most of the oxide on the inlet feeders is formed by precipitation of iron from saturated solution. The amount of oxide on the Unit 2 feeders decreased by a factor of about 2 after each CAN-DECON process. Depth-profiles of trace elements and radioisotopes of the oxide on Unit 2 inlet feeders show that cobalt, nickel and zinc are generally highest at the oxide/metal interface. In addition, the CAN-DECON reagent seems to remove oxide from the oxide/solution interface rather than the oxide/base metal interface.