Management of Ferro‐alloy wastes

Abstract The ferro‐alloy industry in South Africa can be divided into two groups of processes, the first concerned with the mining and initial beneficiation of ores and the second with the production of various metallic products, ranging from pig iron to various ferro‐alloys and stainless steel. Waste production from these processes is considerable, with the majority of waste products in the form of solids, such as furnace slags, emission control dusts, flotation tailings and leach residues. Traditionally, these waste materials have been disposed of to landfill, usually in the form of large‐scale heaps or dams. It is only since recently that the management of ferro‐alloy wastes is starting to be governed by concerns about the long‐term environmental stability of such deposits, which is associated with the potential leachability of salts and heavy metal species contained therein. The concept of Clean Technology is beginning to influence process design options in the sector with the ultimate aim to reduce t...