Introduction to Colloidal Phosphate Ore Flotation Process

Colloidal phosphate rock is a common name for low- to medium-grade sedimentary phosphorus rock, which is mostly "poor and fine". This type of phosphate rock is a phosphate mineral that is often cemented together with fine particles such as dolomite carbonate, siliceous matter, and argillaceous minerals. It has high silicon and magnesium content and is difficult to sort.

Common mechanical flotation processes in colloidal phosphate ore flotation plants are mainly forward flotation, single reverse flotation, forward-reverse flotation, reverse-forward flotation and double reverse flotation.

1. Colloidal phosphate rock positive flotation process: Colloidal phosphate rock positive flotation is to add specific inhibitors to the monomer dissociated ore slurry to inhibit gangue materials, and then add specific collectors to make the colloidal phosphate rock hydrophobic, and then Phosphate minerals are separated by flotation under the action of foaming agent.

This method is mainly suitable for neutral siliceous phosphate rock and sedimentary metamorphic silica-calcium phosphate rock. It is more difficult to separate calcium-siliceous phosphorus rock ore containing high carbonate gangue minerals. During flotation, It is easy to cause problems such as high foam viscosity, difficulty in settling of the concentrate, and excessive content of calcium, magnesium and other impurities.

2. Colloidal phosphate rock reverse flotation process: Colloidal phosphate rock reverse flotation generally uses sulfuric acid or phosphoric acid as a pH adjuster for the slurry and an inhibitor for phosphate minerals, and then uses a cationic collector to remove silicic acid in a weakly acidic medium. The salt gangue minerals are flotated into the foam product, thereby obtaining the phosphate concentrate product in the flotation tank.

This method is mostly suitable for flotation separation of aluminosilicate ores such as quartz, feldspar and non-ferrous metal oxide ores.

3. Forward-reverse flotation process of colloidal phosphate rock: forward-reverse flotation of colloidal phosphate rock first uses anionic collector and gangue mineral inhibitor to flotate phosphorus minerals, and then uses cationic collector and silicic acid. The salt inhibitor reversely floats silicate minerals (MgO impurities) from phosphate concentrate, and the product in the tank is phosphate concentrate. 

This method is mainly suitable for processing calcium-magnesium mixed collophosphate rock with high silicate content.

4. Colloidal phosphate rock reverse-forward flotation process: Colloidal phosphate rock reverse-forward flotation is to first use cationic collectors and silicate mineral inhibitors to reversely float out silicate minerals, and then use anionic collectors and Silicate gangue mineral inhibitors are flotating phosphorus minerals.

This process method is mainly suitable for mixed colloidal phosphate rock with high carbonate content.

5. Double reverse flotation process of colloidal phosphate rock: Double reverse flotation of colloidal phosphate rock generally uses fatty acid salts as collectors for carbonate reverse flotation to enrich dolomite gangue minerals in the foam, and then uses cations The collector serves as a collector for reverse flotation of siliceous minerals, enriching quartz gangue minerals and ultimately leaving the phosphate concentrate in the tank.

This method is mostly suitable for processing high-silicon and magnesium-type mixed phosphate rocks (such as dolomite and quartz gangue, etc.).