The Effect of Removing Hard-to-Grind Minerals from Steel Slag on Efficient Grinding and Hydration Activity

Grinding is usually used to increase the specific surface area of steel slag to improve its activity. However, due to the large amount of hard-to-grind minerals in steel slag, a large amount of energy is wasted in the grinding process. Therefore, the current investigation aims to remove the hard-to-grind minerals in steel slag as much as possible to explore the influence of hard-to-grind minerals removal on efficient grinding and hydration activity. It is found that the removal rate of hard-to-grind minerals in steel slag is the highest when steel slag enters magnetic separation particle size of 1 mm and magnetic field strength of 1400 Gs. Compared with untreated steel slag, the grinding efficiency of treated steel slag can be increased by 22%, and the hydration activity is not affected. Therefore, the treated steel slag improves the efficiency in the grinding process, while the hydration activity is not affected.