Flooding diagram for multi-phase flow in a moving bed

Flooding phenomena typically represent liquid overflow and unstable flow behaviour in a gas-liquid counter-current flow within a fixed bed. Understanding the flooding phenomena in a multi-phase flow sys- tem is important to process design and optimization. This paper presents a study of the flooding phenom- ena in two systems: gas-liquid flow and gas-liquid-powder flow in moving beds. Experiments are con- ducted in a one-dimensional column involving upward gas and powder flow and downward solids and liquid flow. Based on the experimental findings, a correlation is formulated which considers the effects of particle moving and the presence of powder phase. The correlation can be used to generate flooding diagrams to depict flooding and non-flooding regions for multi-phase flow in a moving bed.