Study on Upgrading Low-Grade Phosphate Tailings Based on Mineral Liberation Characteristics

Phosphorus tailings are generated as a byproduct of the beneficiation process, with a high yield and containing various valuable minerals, thus representing a potential phosphorus resource. In this study, the mineralogical composition of phosphate tailings was analyzed using the AMICS testing method. The results were utilized to conduct single-stage and combined gravity separation tests. The investigation focused on the impact of the combined processing method on improving P2O5 grade and recovery rate. It was found that the spiral separator-shaking table-shaking table process increased the P2O5 grade from 14.05% to 28.25%, demonstrating a significant enhancement in the concentrate grade. A concentrate grade of 24.16% with a recovery rate of 45.57% was achieved by the shaking table-middling re-grinding (80% < −0.074 mm)-shaking table process, effectively improving the recovery of the phosphate concentrate. Through process mineralogical analysis and optimization of gravity separation, two integrated mineral processing flowsheets were ultimately identified. These flowsheets provide a viable approach for improving P2O5 grade and recovery rate for low-grade phosphate tailings and serve as a reference for the enrichment of medium and low-grade collophane ore.