TITLE:
The Influence of Geometry on the Fluid Dynamics of Continuous Settler
AUTHORS:
Flávia Daylane Tavares de Luna, Andhros Guimarães da Silva, Ardson dos Santos Vianna Júnior
KEYWORDS:
Settler Design, Multiphase Flow, Sedimentation Efficiency, Circulation
JOURNAL NAME:
Open Journal of Fluid Dynamics,
Vol.10 No.3,
July
10,
2020
ABSTRACT: Settlers are broadly used by industries for separating components with different densities, because they show operational facilities and high efficiency. As they use the action of gravity, they can treat great quantities of effluents with lower energy expenditure. However, the performance of the settler depends on the streamlines inside the equipment, which, in turn, are influenced by the characteristics of the suspended solids, the geometry, and dimensions of the tank. In this paper, the effect of the settler geometry properties on the hydrodynamic in a vertical circular cylindrical tank was investigated. The evaluated parameters were the feed pipe design, the dimensions of the piece of equipment, and the structure of settler bottom. The numerical simulations were performed using the package ANSYS-CFX 16.0. It was considered a turbulent, isothermal, and stationary flow. The Euler-Euler multiphase model and BSL-RSM model turbulence were applied. The recirculation zones were influenced by the separation tank geometrical form. The modification of the feed pipe in the original project reduced the mixture inside the feedwell. The increase of the sedimentation tank diameter improved the performance of water and solid separation, elevating the efficiency by 10.48%, whilst the increase of the tank depth reduced the separation efficiency by 16.72%, in comparison to the original project.