<p>A slag disposal method for disposing of slags produced in furnaces during iron or steel making processes comprises employing the steps of magnetic sorting of masses of crude slags of a size greater than a value ranging between 300 to 500 mm obtained from the furnaces into slags rich in iron (above about 50 to 60 percent) and slags not rich in iron (below about 50 to 60 percent) and then applying a compressive force to the slags rich in iron to cause a coarse crushing and/or deformation to reduce the size and at the same time increase the iron content due to the breaking and separation of the slags from the metal. Further magnetic sorting and sieving after griding are provided to obtain concentrates having high iron content and to improve recovery efficiency.</p>
