Isothermal Enrichment of P-Concentrating Phase from CaO–SiO₂–FeO–MgO–P₂O₅ Melt with Super Gravity

Abstract

In this study, the investigation on the isothermal enrichment of P-concentrating phase from CaO–SiO₂–FeO–MgO–P₂O₅ melt with super gravity was carried out. The results show that there was an obvious stratification appearing in the sample after centrifugal enrichment. The upper part of the sample is loose and porous, while the lower part is smooth and compact. With the help of metallographic microscopy and X-ray diffraction, it is found that the P-concentrating phase gathered in the upper part, while it is hard to find any P-concentrating phase in the lower part of the sample. In addition, the volume fraction and equivalent diameter of P-concentrating phase present gradient distribution along the direction of super gravity. After centrifugal enrichment, the mass fraction of P₂O₅ in the concentrate is up to 4.92%, while that in the tailing is just 1.08%. The recovery ratio of P₂O₅ in the concentrate is up to 72.62% with the gravity coefficient G=600, time t=20 minutes and temperature T=1623 K.