Phosphate ore flotation acid leaching alkali treatment process

Phosphate ore is a non-metallic mineral resource rich in phosphorus, and its main components are compounds formed by phosphorus elements and their oxides. The physical properties of this mineral include color, luster, hardness, cleavage and density.

There are various types of phosphate ores, including red phosphate ore, yellow phosphate ore and purple phosphate ore, and their chemical composition and physical properties are different. For example, red phosphate ore is mainly composed of phosphate minerals such as fluorapatite and chlorapatite; yellow phosphate ore is mainly composed of fluorapatite; purple phosphate ore is mainly composed of chlorapatite. These different phosphate ores are also different in practical applications.

Phosphate ore flotation process

Flotation is an important method in the beneficiation process of phosphate ore. In this process, the crushed ore is fed into the flotation machine, and after adding water and flotation reagents, the ore particles react with the reagents through stirring and aeration to form bubbles and float to the water surface to form a foam layer, which is then collected by the scraper, while the non-phosphate minerals remain in the slurry. Flotation reagents mainly include collectors, depressants and regulators. Collectors make the surface of phosphate ore hydrophobic, which is convenient for bubbles to float; depressants are used to suppress the flotation of non-phosphorus minerals; regulators are used to adjust the properties of the slurry.

Extraction of Phosphorus by Acid Leaching

Acid leaching is a common technique for extracting phosphorus in chemical beneficiation. In this process, the crushed ore is added to the acid leaching tank, and an appropriate amount of acid (such as sulfuric acid or hydrochloric acid) is added to react at a specific temperature and pressure. The role of the acid is to dissolve calcium and other impurities in the ore, while phosphorus is insoluble in acid and remains in the acid leaching residue. Sulfuric acid and hydrochloric acid are commonly used acids, among which sulfuric acid is widely used due to its wide acidity range.

Extraction of Phosphorus by Alkali Treatment

Alkali treatment is another chemical beneficiation technology used to treat phosphate ore. The main steps of this method include crushing, grinding, alkali treatment and filtration. In the alkali treatment stage, the ground ore is added to the alkali treatment tank, and an appropriate amount of alkali (such as sodium hydroxide or calcium hydroxide) is added to react at a certain temperature and pressure. The role of alkali is to dissolve phosphorus in the ore, while other impurities remain in the slag. Commonly used alkalis include sodium hydroxide and calcium hydroxide, of which calcium hydroxide is widely used due to its weaker alkalinity.

Through these processes, phosphorus can be effectively extracted from phosphate ore, providing important phosphorus resources for agriculture and industry.