Optimizing injection modes and reactor shapes in gas-particle fluidized beds using a mesoscale CFD model

We introduce the concepts of 'multi-level-nozzle' and 'continuous oscillatory tapered' fluidized beds to enhance contact efficiency and promote mixing between the gas and particle phases for a pilot-scale turbulent fluidized bed. Before delving into these concepts, we comprehensively assess the mesoscale drag correction model's parameter sensitivity, ensuring its applicability in lab-scale and pilot-scale turbulent fluidized beds, as well as pilot-scale risers. Following this evaluation, we design multiple cases to systematically investigate the influence of injection nozzle numbers, heights, and angles on the hydrodynamic mechanisms, specifically focusing on the degree of particle clustering and intermittency. Furthermore, we explore the effect of reactor shapes in terms of tapered ratios and sub-tapered bed numbers to intensify contact efficiency of two phases. By implementing these conceptual designs, we effectively enhance the intermittent extent of particles by over 30% and achieve higher oscillation frequencies with relatively low instability, leading to intensification of flow quality.

Automated summary

This study introduces the concepts of 'multi-level-nozzle' and 'continuous oscillatory tapered' fluidized beds to enhance contact efficiency and promote mixing between the gas and particle phases in a turbulent fluidized bed. The feasibility of these concepts is assessed through experimental and modeling evaluations. By designing multiple experimental cases, the influence of injection nozzle numbers, heights, angles, and reactor shapes on the hydrodynamic mechanisms is systematically investigated. The implementation of these conceptual designs leads to improved flow quality by enhancing particle intermittency and achieving higher oscillation frequencies.