Intensification of low-grade phosphate ore purification using a hydrocyclone with venturi-style inlet

Abstract

The accumulation of large quantities of low-grade phosphate ore throughout the year occupies land and pollutes the environment. Addressing the challenge of purifying this ore to produce high-grade phosphate is essential for alleviating the shortage of phosphorus resources, making it a pressing research topic. Herein, we propose a hydrocyclone with a venturi-style inlet that combines multiple morphologies to purify low-grade phosphate ore. This innovative design addresses issues with conventional hydrocyclones by reducing short-circuit flow and eliminating circulation flow. Additionally, the new hydrocyclone tackles the overflow entrainment problem of large-density P particles and reduces the possibility of lower-density Si-Mg particles escaping through the underflow pipe, leading to intensified separation performance. The hydrodynamic multiphase flow field characteristics of different hydrocyclone were investigated via CFD simulation to elaborate the reason for the performance intensification. The venturi-style inlet architecture improved the tangential velocity and enhanced the spiral flow field, expanding the length and range of the locus of zero vertical velocity (LZVV) in the primary separation area. This designed hydrocyclone could purify low-grade phosphate ore at lower expenditure and higher performance, with separation efficiency increased from 76% to 92% and precision promoted from 70% to 87% compared to conventional one. This work presented a cheap and efficient technology for purifying low-grade phosphate ore and demonstrated comprehensive potential for the recycling of mineral resources.