Phosphate Ore Flotation Process: Positive Flotation and Reverse Flotation in Two Steps

Current research on phosphate ore beneficiation processes primarily focuses on the removal of silicon, magnesium, and calcium from medium-to-low grade phosphate ore. This is achieved by modifying or optimising the flotation process flow and adjusting the dosage of flotation reagents to fully utilise domestic phosphate ore resources.

1. Direct Flotation

Direct flotation involves adding inhibitors in an alkaline environment to suppress the flotation of gangue minerals such as silicates, thereby concentrating phosphate minerals. Compared to other processes, it has relatively simple process equipment, process environment, and process difficulty, making it easier to implement. It is suitable for sedimentary metamorphic rock-type and igneous rock-type phosphate ores, effectively addressing the issue of low recovery rates in the separation and collection of such ores.

2. Reverse Flotation

The reverse flotation process for phosphate ore primarily separates phosphate minerals from dolomite. By using inhibitors such as phosphoric acid to suppress phosphate minerals and employing specific collectors, the desired minerals are separated. Reverse flotation has no specific temperature requirements and can be performed at room temperature, making it easy to implement with low beneficiation costs.

3 Two-step flotation

The two-step flotation process uses collectors with different properties combined with medium adjusters to remove silicon and magnesium. Common flotation processes include positive-reverse flotation, double reverse flotation, and reverse-positive flotation. Direct-reverse flotation and reverse-direct flotation are used to process silicate-calcium phosphate rock and calcium-silicate phosphate rock. They have strong adaptability and achieve good separation effects for medium to low-grade phosphate ore. Double reverse flotation is primarily used for separating phosphate minerals from quartz and dolomite. Its notable advantage is that it can be conducted at room temperature, resulting in lower overall reaction costs.