8th International Congress on Science and Technology of Ironmaking - ICSTI 2018

A state-of-the-art numerical model was developed for analyzing packed bed structures containing non-spherical solids such as cokes and the high-temperature melt trickle flow characteristics of such beds. This enables the direct 3-dimensional analysis of packed beds that are difficult to visualize in experimental tests. The advanced discrete element method with 3D scanning technology is employed as a highly-accurate method for solid-particle motion simulation. It is a method using a contact force model that is expanded to capture the motion of 3-dimensionaly freely shaped rigid bodies. Meanwhile, the sophisticated smoothed particle hydrodynamics method can track the motion of liquids without discriminating between continuous and dispersed phases. We used the boundary for the packed bed configured with non-spherical solids to carry out gas-liquid-solid 3-phase dynamic simulation. Based on this model, we carried out the large-scale simulations, and perform case studies and other studies of statistical processing, and investigate the effects of both physical properties and packed bed formed from various types of non-spherical cokes. Even for cokes bed of equal volume, different shapes changed the molten slag passage characteristics and static hold-up amount. Since the size of the hold up site is also influenced by the shape of the void at the top of the neck, the flow characteristics on the upstream side of the packed bed can also have a large influence. And we investigated the influence of melt physical properties on trickle flow, and clarified that an increase in viscosity increases holdup because limiting the effective flow path and suppressing the dispersion of the droplets promoted the enlargement of each stagnant droplet.