Host: The Japan Society of Mechanical Engineers
Name : The 30th International Conference on Nuclear Engineering (ICONE30)
Date : May 21, 2023 - May 26, 2023
During the shutdown period of pressurized water reactor nuclear power units, the film-forming amine maintenance technology can effectively inhibit the shutdown corrosion of secondary circuit carbon steel pipelines. In this work, octadecylamine was taken as the research object, and the inner wall of deaerator drain pipe of PWR nuclear power plant were selected as typical service conditions. The maintenance process and adsorption mechanism of octadecylamine on A515-60 carbon steel were studied by using material interface characterization method and thermodynamic calculation software. The influence mechanism of film-forming concentration, duration, carbon steel surface state on octadecylamine adsorption behavior was discussed. The research results are significant for the popularization and application of film-forming amine maintenance technology during shutdown of PWR nuclear power plant.
The maintenance effect of octadecylamine on A515-60 carbon steel and pre-oxidized A515-60 carbon steel surface using one-time dosing was studied by scanning electron microscope, X-ray energy scattering spectrum, high temperature electrochemical measurement technology, weight loss and contact angle measurement. It was found that the best filmforming concentration of octadecylamine on A515-60 carbon steel surface was 20mg/kg, and the best film-forming time was 8h at 168°C.
The adsorption layers of octadecylamine on A515-60 carbon steel and pre-oxidized A515-60 carbon steel were studied by focused ion beam-transmission electron microscope. It was found that the thickness of organic films adsorbed on A515-60 carbon steel in 20mg/kg octadecylamine solution at 168°C was 14nm, and the corresponding adsorption layers were 25. The surfaces of A515-60 carbon steel had multi-layer physical adsorption.
