Extractive metallurgy concentration

Extractive metallurgy covers a huge range of mechanical and chemical processes, some of which date back several thousand years.1,2 In terms of recovery from primary sources (metal ores) these processes are often broken down into the unit operations concentration, separation,... 

Duyvesteyn, W. P. C. Sabacky, B. J. Ammonia Leaching Process for Escondida Copper Concentrates (Reprinted from Extractive Metallurgy of Copper, Nickel, and Cobalt. Vol. 1, 1993). Trans. Inst. Min. Metall. Sect. C-Miner. Process. Extr. Metall. 1995, 104, C125-C140. 

Wadsworth, M.E., 1972. Second Tutorial Symposium on Extractive Metallurgy, Leaching of Low and High Grade Ores, Dump Deposits and Concentrates, Part III, Advances in the leaching of sulfide and oxide minerals. University of Utah. 

R. Audinos, Liquid waste concentration by electrodialysis, Separation and Purification Technology, ed N.N. Li and J.M. Calo, Marcel Dekker, Inc. New York, 1992 T. Sata, Application of ion exchange membrane to hydrometallurgy, Extraction Metallurgy 89, The Institute of Mining and Metallurgy, 1989, p. 977. 

Abstract This chapter is about mineral processing of the rare earths (making the mined ore into a concentrate of the valuable minerals), and extractive metallurgy of the rare earths (how to get the metals out of the concentrate). The mineral processing of three well-known exploited ore deposits is discussed in more detail. 

Primary tin metal is produced from tin concentrates, while some secondary tin metal is also recovered as the byproduct of other nonferrous metal extractive metallurgy or recycling from industries using tin or its alloys. 

Duyversteyn, W. C. and Subacky, B. J. 1993. The Escondida process for copper concentrates. In The Paul E. Queneau international symposium extractive metallurgy of copper, nickel and cobalt, vol. 1, Fundamental aspects, eds. R. G. Reddy and R. N. Weizenbach, 881-910. Warrendale, PA The Minerals, Metals and Materials Society. 

Engineers use the term concentration by weight, as it is easier to convert back into the total tonnage of solids to be transported through a pipeline or across an extractive metallurgy plant. However, the characteristics of the mixture, the mechanics of flow, and the resultant physical properties are more related to the concentration by volume. 

It would be beyond this book to discuss the principles of extractive metallurgy. Slurry is a very important component in the processing of ores to the final disposal of talUngs and shipping of concentrate. Chapter 7 is dedicated to equipment for slurry processing. There are three main processes used for extractive metallurgy ... 

Concentration (1) refers to the composition of a solution. (2) See extractive metallurgy. 

Extractive metallurgy refers to the process of extracting a metal from its ores. Generally this occurs in four steps. Concentration separates the ore from waste rock (gangue). Roasting converts the ore to the metal oxide. Reduction (usually with carbon) converts the oxide to the metal. Refining removes impurities from the metal. 

The abundance of indium in the earth s cmst is probably about 0.1 ppm, similat to that of silver. It is found in trace amounts in many minerals, particulady in the sulfide ores of zinc and to a lesser extent in association with sulfides of copper, tin, and lead. Indium follows zinc through flotation concentration, and commercial recovery of the metal is achieved by treating residues, flue dusts, slags, and metallic intermediates in zinc smelting and associated lead (qv) and copper (qv) smelting (see Metallurgy, EXTRACTIVE Zinc and zinc alloys). 

The treatments used to recover nickel from its sulfide and lateritic ores differ considerably because of the differing physical characteristics of the two ore types. The sulfide ores, in which the nickel, iron, and copper occur in a physical mixture as distinct minerals, are amenable to initial concentration by mechanical methods, eg, flotation (qv) and magnetic separation (see SEPARATION,MAGNETIC). The lateritic ores are not susceptible to these physical processes of beneficiation, and chemical means must be used to extract the nickel. The nickel concentration processes that have been developed are not as effective for the lateritic ores as for the sulfide ores (see also Metallurgy, extractive Minerals recovery and processing). 

Nonferrous Metal Production. Nonferrous metal production, which includes the leaching of copper and uranium ores with sulfuric acid, accounts for about 6% of U.S. sulfur consumption and probably about the same in other developed countries. In the case of copper, sulfuric acid is used for the extraction of the metal from deposits, mine dumps, and wastes, in which the copper contents are too low to justify concentration by conventional flotation techniques or the recovery of copper from ores containing copper carbonate and siUcate minerals that caimot be readily treated by flotation (qv) processes. The sulfuric acid required for copper leaching is usually the by-product acid produced by copper smelters (see Metallurgy, extractive Minerals RECOVERY AND PROCESSING). 

Copper ore minerals maybe classified as primary, secondary, oxidized, and native copper. Primaryrninerals were concentrated in ore bodies by hydrothermal processes secondary minerals formed when copper sulfide deposits exposed at the surface were leached by weathering and groundwater, and the copper reprecipitated near the water table (see Metallurgy, extractive). The important copper minerals are Hsted in Table 1. Of the sulfide ores, bornite, chalcopyrite, and tetrahedrite—teimantite are primary minerals and coveUite, chalcocite, and digenite are more commonly secondary minerals. The oxide minerals, such as chrysocoUa, malachite, and azurite, were formed by oxidation of surface sulfides. Native copper is usually found in the oxidized zone. However, the principal native copper deposits in Michigan are considered primary (5). 

The 8-hydroxyquinoline method was applied for determination of aluminium in plant materials [15,76,77], soil extracts [76], silicate rocks and minerals [2], cast iron and steel [1,8,9,14], nickel- and copper alloys [1], chromium [78], beryllium [79], metallurgy products [80], titanium concentrates [7], and phosphates [81]. 

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