Adequação granulométrica das matérias-primas e do sistema desegregação contínua (I.S.F), para melhorias na produtividade e qualidadedo sínter para os altos-fornos

Abstract

One of the characteristic features of the traditional sintering process is the non uniformity of the reaction intensity in the vertical direction of the sinter bed. The sintering reactions, which reflect the heat level of the process, proceed insufficiently in the upper layer and excessively in the lower layer of the sinter bed. This results in sinter with different quality along the height of the sinter bed. The idea of homogenization ofthe reaction with heat balancing by producing carbon segregation in the upper layer of the sinter bed can be traced back to the old period. However, this situation has now significantly changed with the advent of a new accessory to the mixture charging system, called the Intensified Sifting Feeder I.S.F. This device promotes a favourable size segregation of the mixture in the sinter bed leading to a gain inpermeability. With a proper size distribution of the fuels, fluxes and even the iron ore it is possible to reduce the reaction and thermal heterogeneity by moving preferentially the fuel and fluxes to the upper regions of the bed. With the installation of I.S.F in Usiminas sintering machines, several studies have been developed aiming to generate support data for improving size specifications of raw materials.The objectives of this study are i) consolidate the performing increase of sintering machine after the installation of I.S.F and granulation of the mixture components to be sinter. ii) adjustment granulation in serpentine to get the sinter if a better physical and metallurgical quality for the blast furnaces. The study program will involve the data statistics, shoeing a better sintering performance after the I.S.F installation and granulation adjustment of mixture components to be sinter, as well as new samples of mixtures before sintering and sinter cake, after new granulation adjustment in serpentine.