Аеродинамічне розділення залізорудних окатишів по крупності

Abstract

The studies on reheating of fired pellets of a suitable fraction used in the bottom and side beds have been analyzed. It has been shown that due to the loss of the crystallization of the glass iron silicate bond, the strength of the pellets decreases at their reduction and their destruction in the metallurgical unit increases, thus leading to a deterioration in its performance. It has been concluded that for the bed, it is necessary to purposefully separate the fraction of the pellets of the required size that does not fall into the finished product. The ways of organizing air classification of fired pellets in open warehouses of finished products have been studied and the possibility of its organization has been considered. The particle trajectories and the factors influencing this process have been analyzed. It has been shown that an important characteristic of the particles dispersion is the influence of the ratio of the coefficient of viscous resistance to the flight of a particle in the air to the mass of a particle, as a result of which an initially flat flow for the particles of different sizes will disintegrate into a fan. This fan of the particles scattering at a certain height can be used to sort them by size class. The conditions have been determined under which the dispersion of the fan of the particles in the horizontal plane will be maximum. Equations have been proposed to describe the law of motion of particles before hitting the jet and after having been blown off by the jet. Mechanisms have been developed for selecting design conditions under which the horizontal distances between the particles of different sizes (the difference of the corresponding coordinates) at the set horizon will be maximum and sufficient for sorting the particles by their size. The visualization of the process of the particle scattering in the MathCAD software environment has been performed, which makes it possible for the technologist to set the initial conditions he needs and to obtain clearly presented final results of the motion of a fan of the particles of different sizes that are clear to him