Sludge collector performance in steam generators of pressurized water reactor

Corrosion products produced within a Pressurized Water Reactor plant's secondary system flow into and concentrate in the steam generators (SG's). These corrosion products, which mainly consist of magnetite accumulate in regions of stagnant flow and deposit on the surface of the heat transfer tubes. These deposits are referred to as 'sludge'. Harmful impurities also contained in secondary water may concentrate next to the tubes within these sludge deposits and can cause tube corrosion. This paper reports on a 'sludge collector' that separates suspended solids from the secondary water inside the SG in a region away from tube bundle. The operating principle, supporting analysis and laboratory test data, and field test results are described.