Magmatic apatite and sedimentary metamorphic apatite

Phosphate ore is composed of phosphate minerals. The main mineral is apatite, with the chemical formula of Ca5[PO4]3 (F, OH, Cl).

The main gangue minerals in phosphate ore are silicate minerals, carbonate minerals, and siliceous materials such as quartz. The floatability of phosphate minerals is quite different from that of siliceous minerals, so they are easy to separate, while the floatability of phosphate minerals is similar to that of carbonate minerals, so they are difficult to separate.

1 Magmatic apatite

The main components of magmatic apatite are fluoroapatite and a small amount of chloroapatite, accompanied by vanadium, titanium, iron, cobalt and other elements, and often coexist with minerals such as magnetite, silicates and metasilicates. The P2O5 grade is low, generally less than 10%. The crystallization and distribution particle size are coarse, the selectivity is good, and the beneficiation method is simple. After sorting, the P2O5 content in the concentrate is above 35%, the recovery rate is greater than 80%, and the associated minerals can be comprehensively recovered, which has the value of development and utilization.

The beneficiation method of igneous rock apatite is mainly flotation. Inhibitors such as water glass are used to inhibit gangue minerals, and anionic collectors such as fatty acids are used to enrich phosphate minerals in flotation foam, and apatite is directly floated out.

2 Sedimentary metamorphic rock type apatite

The main component minerals of sedimentary metamorphic rock type apatite are the same as those of igneous rock type apatite. They often coexist with carbonate minerals (mainly dolomite), silicate minerals, and siliceous materials. When carbonate minerals (dolomite) are associated, the quality of phosphate concentrate is affected. The P2O5 grade is 8%~12%, the crystal particle size is coarse, and the flotation performance is good.

Since the phosphorus minerals in apatite are coarsely embedded and have good floatability, positive flotation is often used to float apatite. Sodium carbonate and water glass are used as adjusters to inhibit carbonate minerals, silicate minerals and siliceous materials, and fatty acids and other anionic collectors are used to float apatite.