The dissolution rate constant of magnetite in ammoniated water at 140 °C and a pH25°C of 9.2
University of New Brunswick
Corrosion of carbon steel components is a major problem in the power generation industry and has been proved to be reliant on the protective magnetite oxide layer. Predicting the corrosion rates and material transport with the use of developed models has indicated the importance of a reliable value for the dissolution rate of magnetite at various chemistry conditions. In this study an impinging jet test section was placed in a high pressure recirculating water loop to measure the dissolution of sintered magnetite pellets made from synthesized magnetite powder. The dissolution experiments were conducted under typical power plant feedwater conditions in ammoniated water at pH [subscript 25°C] 9.2. The addition of film-forming amines to the coolant was also studied to determine their effect on the dissolution rate of magnetite. The findings in this study can be used to understand and reduce the dissolution and removal of the protective magnetite oxide layer, which will reduce flow-accelerated corrosion rates, fouling of heat transfer surfaces due to material transport and the level of radioactivity in nuclear power plants due to the deposition of radioactive corrosion products outside of the core.