Patent ID: 9650688
Date: 2017-05-16
CPC Classifications: C21B,C21C,C22B,Y02P

Claim:
1. A method of recovering Fe from a steel-making slag, the method comprising the following steps of: melting the steel-making slag having a higher Fe content than an iron-making slag by heating the steel-making slag to a first temperature ranging from 1450° C. to 1600° C. to make a molten slag; cooling the molten slag to a second temperature ranging from 1150° C. to 1250° C. and then maintaining the second temperature for 10 minutes or longer, thereby forming and growing an Fe-rich spinel phase and an Fe-poor amorphous phase; rapidly cooling the molten slag to room temperature to form a solidified slag after maintaining the second temperature for 10 minutes or longer; and crushing the solidified slag and separating a magnetically-susceptible portion from a magnetically-unsusceptible portion by applying a magnetic separation to the solidified slag, wherein, in maintaining the second temperature for 10 minutes or longer, the Fe-rich spinel phase is formed and grown, and the Fe-poor amorphous phase is formed from an Fe-depleted liquid slag, and wherein an Fe-rich slag from the Fe-rich spinel phase and an Fe-poor amorphous slag from the Fe-poor amorphous phase are separated from each other by the magnetic separation.