Mathematical models and expert system for grate-kiln process of iron ore oxide pellet production (Part I): Mathematical models of grate process

Abstract

Grate process is an important step in grate-kiln pellet production. However, as a relatively closed system, the process on grate is inaccessible to direct detection, therefore, it is hard to control. As a result, mathematical models of temperature distribution, moisture distribution and oxidation degree distribution in pellet bed, with good universality, computation speed and calculation accuracy, are presented based on analysis of heat transfer and physical-chemical reactions during grate process. And real-time visualization of temperature, moisture and oxidation degree distribution in pellet bed during grate process is realized. Model validation is displayed, and the similarity of 91% is proved. The results can reveal real time status on grate, and provide a solid foundation for the subsequent study of artificial intelligence control system of pellet production.

Keywords

mathematical model / temperature distribution / moisture distribution / oxidation degree distribution / iron ore oxide pellet

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