Billinton Group

Recommended Application Flowsheets

Two flowsheets are recommended as follows:

Open Circuit

When an open circuit process is applied, the iron concentrate generated from the automatic elutriated magnetic separator is the final iron concentrate, and the material in the overflow from the machine is discarded as tailings. 

Advantages: the process is simple and the concentrate grade is upgraded significantly.

Disadvantages: it will affect the metal recovery rate. The amount of magnetic iron material in tailings can be usually controlled to be less than 1.5%. Practical experiences indicate that because the amount of tailings from overflow is quite small, there is little effect on tailing grade. 

Closed Circuit

When a closed circuit process is applied, the iron concentrate generated from the automatic elutriated magnetic separator is the final iron concentrate, and the material in the overflow from the machine is intergrowths with larger sizes but low Fe grades. This material is treated as middlings after scavenger of a regular magnetic separator. The middlings are then sent for regrinding to make iron grains to be liberated and to be separated further.

Advantages: the recovery rate of the magnetic iron from the general process is high.

Disadvantages: it has to add one more scavenging magnetic separator. As some super fine low Fe graded intergrowths are likely to form an internal circulation in the process, it will eventually affect the final Fe grade of the concentrate.