Insights into Particle-Wall Interactions Phenomena in Entrained Flow Gasifiers by Numerical Simulations

This poster will illustrate the new insights gained on the fate of char and ash particles in entrained flow gasifiers, upon particle interaction with the reactor walls, by conducting numerical simulations at different levels of detail. Several computational studies, supported by experimental evidences, have been conducted to investigate the swarm dynamics of these particles, always present in large number especially close to the internal walls of the gasifiers (Ambrosino et al., 2013; Marra et al., 2017). The possibility that different regimes can establish, taking into account simple solid-solid interactions, was already postulated in the past (Montagnaro and Salatino, 2010). The effective mechanisms and governing parameters are now emerging from detailed simulations focused on the dynamics of multiparticles confined systems. The results allow to identify the key role of both rheological properties, with a predominant effect of the coefficient of restitution of the gasified material during its transformations, and operative parameters, having in this case the momentum flux and the number density of the particle phase a decisive effect on the kinetic energy dissipation. As a result, a new and different interpretation of the very good conversion performances measured in entrained flow gasifiers is obtained.