Effect of hydrocyclone design in microplastics-water separation by using computational fluid dynamics simulations

Abstract

Nowadays microplastics have become a significant environmental concern, impacting both freshwater and marine ecosystems. In response to this issue, extensive research has been conducted to explore methods for separating microplastics from water. One area of investigation involves the use of computational fluid dynamics (CFD) models to study hydrocyclones and their intricate flow patterns. In this study, CFD was systematically used to examine various hydrocyclone designs with different geometrical parameters, including the ratios of cylindrical diameter to underflow diameter and overflow diameter, the cone to cylindrical height ratio, and the inlet angle. The efficiency of these hydrocyclones has been evaluated based on key performance metrics, including microplastics recovery percentage, water split percentage, and pressure drop. The results of this study have revealed noteworthy findings. Moreover, statistical analysis, specifically the analysis of variance (ANOVA), was employed to determine the significance of various geometric parameters on microplastics separation within the hydrocyclone. As a result of this comprehensive investigation, an optimized hydrocyclone design was proposed. This optimized hydrocyclone featured an underflow diameter to diameter of the cylindrical ratio of 0.264, an overflow diameter to diameter of the cylindrical ratio of 0.3, a cone to cylindrical height ratio of 13.22:70.78, and a tangential inlet. This configuration achieved a remarkable 76% microplastics recovery, a 52% water split, and a pressure drop of 82,340 Pa.