Harsco's steel mill services include onsite logistics, semi-finished product dimensioning and scarfing, and the recycling of steelmaking by-products. We specialize in processing steel slag, millscale, refractories, dusts, sludges, and also steelmaking flue gases, each of which relies on a different resource recovery technology.
In addition to those before me, having spent 33 years in concrete technology, I have no doubt that I can answer another aspect of the life of steel mill slag. Ground granulated blast furnace slag (GGBFS, or just "slag") is a very useful supplementary cementitious material.
The slag occurs as a molten liquid melt and is a complex solution of silicates and oxides that solidifies upon cooling. Virtually all steel is now made in integrated steel plants using a version of the basic oxygen process or in specialty steel plants (mini-mills) using an electric arc furnace process.
The slag produced can be used as concrete admixture, reducing the project costs significantly and enhanced the compressive strength, tensile strength, shear strength and bending strength of the concrete.The optimal performance of ball mills (slag ball mill) is the key to a successful plant operation.
Slag from steel mills in ferrous smelting, on the other hand, is designed to minimize iron loss and so mainly contains oxides of calcium, silicon, magnesium, and aluminium. Any sandy component or quartz component of the original ore automatically carries through the smelting process as silicon dioxide.