How to remove phosphorus from high phosphorus iron ore?

High phosphorus iron ore is a kind of iron ore with high phosphorus content, which makes it difficult to be smelted and affects the quality of steel products. Therefore, it is necessary to remove phosphorus from high phosphorus iron ore.

There are several methods for removing phosphorus from high phosphorus iron ore, including mechanical beneficiation, roasting-magnetic separation, and leaching-precipitation.

1. Mechanical beneficiation

The mechanical beneficiation method mainly includes crushing, screening, washing, and gravity separation. After crushing and grinding, the high phosphorus iron ore is separated from the gangue minerals by gravity separation. However, the phosphorus content in the concentrate is still high, which needs further treatment.

1. Roasting-magnetic separation

The roasting-magnetic separation method is suitable for the iron ore with phosphorus content less than 0.3%. The high phosphorus iron ore is roasted in a reducing atmosphere to convert the iron ore into magnetite, and then magnetic separation is used to separate the magnetite from the gangue minerals. During the roasting process, the phosphorus is oxidized into phosphorus pentoxide and volatilized.

1. Leaching-precipitation

The leaching-precipitation method is suitable for the high phosphorus iron ore with phosphorus content more than 0.3%. The high phosphorus iron ore is leached with an acid solution to dissolve the phosphorus, and then the phosphorus is precipitated by adding a precipitant. The precipitated phosphorus can be recovered and utilized. The leaching-precipitation method has the advantages of high phosphorus removal rate and low energy consumption, but it is not suitable for large-scale production due to the complicated process.

In conclusion, removing phosphorus from high phosphorus iron ore is a key step in the iron and steel industry. The selection of the phosphorus removal method depends on the content of phosphorus in the iron ore, the scale of production, and other factors. The mechanical beneficiation method is simple and suitable for low-grade iron ore, while the roasting-magnetic separation method and leaching-precipitation method are more effective for high-grade iron ore.