STUDY OF DIFFUSION OUTPUT OF IRON FROM EP823 STEEL INTO LEAD MELT

Abstract

The problem of taking into account the release of metallic impurities from steels into heavy heat carriers is important from two points of view. First, the intensity of these impurities entering the coolant directly affects its quality, the formation of deposits based on oxides of metal components of structural steels in the primary circuit, as well as contamination of the gas system and the radiation environment. In addition, the process of the entry of metallic impurities into the coolant during the development of the oxidative nature of its interaction with steels determines the kinetics of this interaction and should be taken into account in oxidation models, especially with an increase in the duration of contact between steel and the coolant. At present, in world practice, despite the understanding of the importance of taking into account the losses of metal components of steels into the coolant, there is no adequate physical model for accounting for these losses. Basically, one or another empirical or semi-empirical approach is proposed. A new experimental data processing technique to verify the model of the release of iron into the lead coolant is presented in the article. It’s based on the analysis of the deoxidizing stage of the process of regulating oxygen TDA in the volume of the coolant. Series of experiments was carried out with varying temperature conditions in the range from 500 to 635 °C and the oxygen mode of CO = (1 ÷ 4) 10-6 wt%. It is shown that the diffusion models of iron yield and oxygen consumption describe well the experimental results and can be used in calculation codes for mass transfer in circuits with HLMC. The numerical values of the parameters characterizing the yield of iron in HLMC depending on the TDA of oxygen and the temperature of the liquid metal under conditions of natural convection are obtained.