| Mass transfer is an important consideration in the design of multiphase contactors. While gas-liquid mass transfer is important for two-phase contactors, both gas-liquid and liquid-solid mass transfer need to be considered for the design three-phase contactors. Many industrial processes such as coal liquefaction, petrochemical, waste water treatment or fermentation processes involve gas absorption in a liquid with or without the presence of inert or catalyst solid particles. When mass transfer is the rate limiting step, the overall rate can be improved by enhancing the rate of mass transfer. This study investigated gas-liquid and liquid-solid mass transfer in bubble columns and three-phase fluidized beds using different types of distributors and coalescence inhibitors. A systematic study was conducted to investigate the effects of molecular structure of various types of coalescence inhibitors. Hydrodynamic parameters such as phase holdups, liquid mixing and flow regimes were also determined. Available literature correlations were tested and their limitations were pointed out. Suitable new correlations were developed based on the data of this study. |
