NUMERICAL ANALYSIS OF THE MULTIPHASE FLOW OF THE AERATION PROCESS IN AN AERATED POND

Abstract

Aerated ponds are essential in water treatment systems. However, fecal-oral transmission is a common dissemination route for many viruses, for this reason, aerated ponds could become unsafe within the current scenario of COVID-19 global pandemic. This paper has employed a CFD approach to study how the aeration process in an aerated pond can promote possible virus transmission. An aerated pond located in a water treatment plant in the city of Guayaquil, Ecuador was studied. A two-dimensional domain was developed with a structured mesh validated with a sensitivity study. The multiphase volume-of-fluid model is used to simulate the aeration process with a k-ε realizable turbulence model, and a discrete phase model is used to model the trajectories of water droplets due to the turbulence of the aeration process. The trajectory of water droplets was modeled, reaching a maximum height of 26.3 cm above the surface of the pond with a velocity of 1.38 m/s. The effect of promoting possible virus transmission by these droplets turned out to be low, compared to other processes considered. Nevertheless, parameters such as inlet air velocity, number of aerators and air flow rate could change due to design and operating conditions of water treatment systems, resulting in a possible increase of the maximum height of the water droplets. © 2022 Begell House Inc.. All rights reserved.