Numerical simulation of hydro-cyclone separator used for separation of highly dense suspended particulate matter

Abstract

Cyclone separators are the most cost-effective and economically gas separation devices. They are not very complex to design and offer high collection efficiency; still, their use for the waste management field, i.e., separating solid waste from the liquid, is not explored to its full extends. This paper presents a Computational Fluid Dynamics-based numerical simulation of a hydro-cyclone separator planned to separate suspended particles from the digestate of a biogas plant. The turbulent incompressible flow model is employed during the simulation. The discrete particle method is used to model and track the suspended solid particle trajectory. The fluid properties of the digestate are assigned to the fluid supplied with suspended particle sizes ranging from 10 to 100 µm during the simulation to obtain realistic flow results. The Stairmand high-efficiency hydro-cyclone geometry is redesigned by the numerical experiment method to obtain high collection efficiency for solid particles. Here the effect of inlet flow velocity and suspended solid particle diameter are simulated to understand their effects on the hydro-cyclone collection efficiency. The fluid flow dynamics are observed, and the detailed distribution of particles inside the hydro-cyclone is presented.