ZINC COATINGS APPLIED IN THE MINING MINERALS INDUSTRY IN SOUTH AFRICA

摘要

South Africa has long had a reputation for being a leading minerals supplier to the world. The country is the number one supplier of gold and platinum group metals and the world's sixth largest supplier of coal. The South African mining industry contributes 33% of the goods export revenues of the country. Gold, platinum and coal together contribute 85% of this figure. A summary of the background to the corrosivity within the mining and minerals industry is presented. Zinc coatings have been used for corrosion protection in the mining and minerals industry for many years. Much data has been gathered on the corrosivity and corrosion protection systems employed in the coal and gold mining industries. This paper seeks to widen the knowledge base by covering other mineral industries, viz. base metal refining, aluminium smelting and platinum mining. This will be discussed as a series of case histories illustrating the different approaches taken by various companies with reference to the background behind the decision making process. Specific reference will be made to the importance of providing user guidance through industry accepted standards. A number of specific projects will be discussed covering a wide range of applications and time frames. These range from the recently opened Anglo American Skorpion zinc mine and refinery, the vertical shaft at the Black Mountian, Bafokeng Rassimone Platinum Mine, the Mozal aluminium smelter, the steel work at the Moab Khotsong mine and the Kinross mine. The use of zinc coatings in the transportation area (conveyors, piping and port facilities) will also be discussed.