Improvement of the Performance of the Hydrodynamics in the Diluted Compartment of an Electrodeionization Reactor

The hydrodynamic behavior of the electrodeionization reactor allows the improvement of the performance of the process as a whole. The challenge lies on the adequate modelling of the packed bed compartment, due to the particle size of the ion exchange resins.

The present study focusses on the improvement of the hydrodynamic behavior of the diluted compartment to achieve a plug flow in the diluted compartment of the reactor by adjustments in the geometry design via CAD.

The reactor, with 32cm² ion exchange membranes, has two concentrated and one diluted packed bed compartment where the solution to be treated is introduced to the reactor and deionized while being in contact with the ion exchange resin.

Using CFD software, the existing geometry for the reactor was simulated and then subsequent variations were made to achieve a plug flow in the diluted compartment, minimizing the stagnant and channeling zones.

The results, allow the study of the velocity profiles in the compartment for the different geometries modeled and the selection of the configuration that allow the removal of the maximum quantity of ions from the inlet solution.