MATHEMATICAL MODELING OF AN AIRLIFT FLOTATION COLUMN WITH DIFFERENT GEOMETRIES FOR WATER AND OIL SEPARATION

Petroleum is one of the top commodities in the world, which produces some of the most environmentally hazardous wastes, such as produced water. Thus, research on technologies capable of processing wastewater are important for promoting the treatment of this waste and reducing costs in the segment. Among the processes used to treat wastewater, flotation is one of the leading methods used in physical separation operations. The efficiency of this technique has a high influence on internal hydrodynamic flows. This paper proposes a mathematical modeling to fluid dynamics of oil-water separation in an airlift flotation column based on momentum and continuity balance equations. To simplify the modeling used, we considered only the drag force as the most relevant interfacial force in this phenomenon. The software Ansys CFX 13.0 was used to evaluate the data. Three columns were created, and all data were submitted to a simulated effluent, containing 1000 ppm of oil. By evaluating efficiency selection in three columns and observing the countercurrent design, we found 84.72% as the best result achieved. This result can be associated with a column model that allows better phase contact as an ideal turbulence in the recirculation zone. Despite the simplifications in the proposed model, it is possible to observe a good association between the results obtained in the simulations and the ones presented in the literature.