Hydrodynamic analysis of different baffle layouts in a facultative pond to mitigate operational problems through computational fluidodynamics

Abstract

The main operational problems found in facultative ponds are the dead zones, short circuit zones of recirculation zones, caused mainly by the accumulation of solids in the bed. The use of baffles is one way of mitigating these problems. Thus, the objective of this work is to compare four baffle installation formats in an optional pond using computational fluid dynamics, and subsequently to identify the occurrence of the main operational problems in each model. For the development of the study, the software Ansys 14.5®was used, where the geometry of the analyzed pond was replicated, including in each model a different layout of the baffles. The use of deflectors allowed the mitigation of the main problems, such as the accumulation of sediments, and it was able to increase the flow velocity in all scenarios, as well as bringing the hydraulic retention time closer to that of the project. According to the data obtained, and the visual analysis of the simulations, it is possible to affirm that the baffle layouts assessed in scenario four would be more adequate to mitigate the operational problems found in the studied pond, as this arrangement conditions the flow of the piston type, which provides less sediment accumulation and the development of dead zones and short circuit zones in the bed. It was concluded that the installation of baffles could mitigate the operational problems of stabilization ponds by directing the flow. Likewise, there was a need for continuous studies to improve wastewater treatment systems.