Energy saving from furnace slag: Study on centrifugal granulation characteristics of the rotating cup

Dry centrifugal granulation technology is an important mean for liquid high-temperature slag. In this paper, the numerical simulation of dry granulation process was carried out to analyze the stretching and splitting process of liquid filaments and study the effects of various factors on liquid filaments and granulated droplets. The results showed that when rotating speed was higher than 1100 rpm, the granulation mode transitioned from sheet mode to ligament mode. When rotating speed reached 3000 rpm, it entered droplet mode. When rotating speed increased, the droplet diameter decreased and the distribution concentration increased. The ratio of the liquid filament diameter to the droplet diameter was approximately 0.7. The increase of the viscosity increased the filament length and the average droplet diameter. Moreover, the increase of the surface tension also increased the average droplet diameter. When the inclination angle of the cup was 45°, the granulated droplets diameter obtained was small.