The Accelerated Corrosion of CANDU Outlet Feeders - Observations, Possible Mechanisms and Potential Remedies

Abstract

The outlet feeders at all of the CANDU-6 reactors and at several of the Ontario Hydro reactors are corroding at rates that are much higher than were ever predicted from measurements in autoclaves or out-reactor loops. Over the last year since the phenomenon was discovered a flurry of activity at the operating reactors and research laboratories has indicated the origins of the important mechanisms involved; at the same time, clues as to possible remedies have emerged. A summary of some of that activity, centred on the experience at the CANDU-6 at Point Lepreau and the research at the University of New Brunswick, is presented here.