Application of Falcon centrifuge in the separation of siliceous phosphate ore

Abstract

Efficient desilication of siliceous phosphate ore is an urgent problem in utilizing phosphate resources. The work evaluated the effect of Falcon centrifuge in separating siliceous phosphate ore and proposed a new combined process of Falcon centrifugal separation and flotation. Three factors were utilized, including rotational frequency, backwash water pressure, and feed rate. The influence model of the three factors on P2O5 recovery was established through orthogonal experimental design, and the optimal prediction index was obtained and proved by laboratory tests. A maximum P2O5 recovery of 86.02% with 27.45% of P2O5 grade was obtained at a rotational frequency of 64.73 Hz, a backwash water pressure of 0.012 Mpa, and a feed rate of 30.51 mL/s. The size analysis revealed that the loss of valuable minerals mainly existed in the −0.045 mm size fractions. The mineral constituent and apparent morphology were analyzed by MLA and SEM-EDS. The optimization experiments of narrow particle size fraction showed that the sorting effect of the particle size between 0.045 and 0.09 mm was optimal. The new process reduced the grinding cost and the feed of flotation, providing a simple and effective new approach to beneficiate siliceous phosphate ore.