Improvements Made to the Bruce A Upgraders and Heavy Water Cleanup System as Part of the Bruce A Units 1 and 2 Restart Project and Commissioning Results

Abstract

As part of the Bruce A Units 1 and 2 Restart Project, major modifications and maintenance were completed on the heat transport and moderator upgraders and the heavy water cleanup system. This represents the first time that major rehabilitation has been done to such systems in a CANDU nuclear station for the purpose of life extension. Prior to shutdown in 1997, the upgraders and cleanup system significantly underperformed against the stated design. The rehabilitation, which included major design changes and implementation of new systems, resulted in the upgraders exceeding design throughput and making product with quality much better than specified. This paper describes the work done, results from inspections and follow-up, and performance data from commissioning.