Steam Generator Cleanliness Management A Comprehensive Concept for CANDU Plants

Abstract

Steam generator tubes are by far the largest boundary between the primary and secondary side. Moreover, the over¬all performance of the plant depends strongly on the SG. The steam generator efficiency can be negatively affected by magnetite deposition on the tubes on either the ID (inner diameter) or OD (outer diameter). These deposits are a threat to the integrity of the SG due to either ID or OD corrosion. Deposits in the steam generators may promote corrosion phenomena, leading in the worst case to a steam generator replacement. Therefore, a comprehensive cleanliness concept, based on optimized water chemistry and chemical and mechanical cleaning processes is mandatory and will be outlined in the following paper.