Bubble column reactor design using a CFD code

This work is motivated by the need to develop reliable predictive tools for bubble column reactor design using a CFD code. Although bubble columns are widely used in industrial gas-liquid operations, their design and scale up is still a difficult task and subject to errors, due to the generally complex structure of the multiphase flow encountered in this type of equipment. Population balance equations combined with a threedimensional model were used in order to study the operation of a rectangular bubble column. In addition, the mechanisms of bubble coalescence and break-up were considered into the Eulerian-Eulerian simulation, while being applied to a multiple size group model. Computational results have been compared to experimental data and it appears that bubble size distribution, axial liquid velocity and gas holdup can be well predicted at the homogeneous regime for the air-water system. The results acquired for the air-water system were encouraging and the simulations are to be extended to gas-liquid systems where the liquid phase is other than water. However, additional experimental work at the microscopic level combined with theoretical analysis are considered necessary for establishing CFD codes that will successfully predict the behavior of bubble column reactors.

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