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Smelting of copper

Many nonferrous metals can be extracted by reduction smelting, eg, copper, tin, nickel, cobalt, silver, antimony, and bismuth. Blast furnaces are sometimes used for the smelting of copper or tin, but flash and reverberatory furnaces are more common for metals other than lead. [Pg.167]

Despite low collection efficiencies, settling chambers have been used extensively in the past. The metals refining industries have used settling chambers to collect large particles, such as arsenic trioxide from the smelting of copper ore. [Pg.393]

The main sources of rhenium are the molybdenite and coliunbite ores. Some rhenium is recovered as a by-product of the smelting of copper sulfide (CuS) ores. Molybdenum sulfide (MoSj) is the main ore and is usually associated with igneous rocks and, at times, metaUic-like deposits. Molybdenite is found in Chile, as well as in the states of New Mexico, Utah, and Colorado in the United States. [Pg.156]

Uses/Sources. In wood preservatives metallurgy for hardening copper, lead, alloys pigment production manufacture of certain types of glass insecticides and fungicides, rodent poison a by-product in the smelting of copper ores dopant material in semiconductor manufacmre... [Pg.55]

Smelting of copper begins in Egypt and parts of Europe. [Pg.30]

Job s statement that brass is molten out of the stone must refer to the smelting of copper from its ore (Job 28,2). Similarly, the two mountains of brass which Zechariah described in the vision of the four chariots must have been mountains of copper or its ore (Zech. 6, 1) (37). [Pg.21]

In the smelting of copper ores some selenium is found in the flue dust the amount may be as much as 12 per cent., whilst some passes into the anode slimes of the electrolytic refineries. [Pg.287]

Among the technologies in existence by ca 4000 bc, which included the manufacture of synthetic lapis lazuli, the development of the first true pottery kilns must rate as a significant achievement (1). For polychrome pottery to be successfully manufactured, it was essential to separate the fire (fuel) from the work (clay pottery). The excavations performed in the near east (Mesopotamia in antiquity) indicate that these early kilns were probably of beehive construction. Subsequent Egyptian pottery kilns of the period ca 3000 BC were the familiar chimney shape. With the smelting of copper in pit hearths predating by perhaps a millenium millennium the start of the Bronze Age at ca 3000 BC, another important advance was the invention of the bellows at ca 2000 BC. Bellows supply combustion air where it is needed and are used as a means of raising furnace temperature. [Pg.140]

Before 1914, the US imported most metallic arsenic from Germany (e.g., Smith, 1945). From 1914 to about 1930, the bulk of the arsenic production in the US (marketed for commercial applications as As203, arsenic trioxide, or white arsenic) was derived as a metallurgical by-product of the smelting of copper, lead, and gold. Arsenic trioxide was used in the production of fertilizers, herbicides, and insecticides (Kirk-Othmer, 1992 Ullman s Encyclopedia, 1998), or if transformed to arsenic acid, used in the manufacture of CCA, a preservative of wood products (Mineral Commodity Summaries, 2004). Arsenic metal is also used for solders, ammunition, anti-friction additive to bearings, and in the computer and electronics industry for semiconductors (Mineral Commodity Summaries, 2004). [Pg.306]

Arsenic is a by-product of the smelting of copper, lead, and zinc ores. It has been shown to produce acute and chronic toxic effects, with the trivalent (3+) form as the most toxic. Arsenic has been classified in the EPA s Group A (human carcinogen), and it is regulated by the U.S. government. [Pg.484]

Of the total quantity of thallium mobilized by industry amounting to about 1600 tons in the United States during 1977, 70% was reemitted to the environment either in the form of air pollution (15%) or as solid waste (55%). Coal burning power plants account for the greater part of this air pollution, but the smelting of copper, zinc, and lead may also result in concentrated local emissions. The remaining 30% is incorporated in the final products, though usually at a lower level than in the raw materials. ... [Pg.4824]

Properties Copper (96-99% purity) produced by the reduction and smelting of copper ores. It has a blistered appearance, probably caused by gas pockets. It is usually further refined electrolytically. [Pg.169]

Froth flotation is used to raise the low mineral concentrations in ores to concentrations that can be more economically processed. A concentration of 25-30% is suitable for economical smelting of copper. The froth flotation technique was originally developed in about 1910 to raise the copper concentrations of the strip-mined ores of Bingham Canyon, near Salt Lake City [9], and was further perfected for the differential separation of lead, zinc, and iron sulfides at Trail, B.C., at about the same time [10]. Flotation technologies are now widely used for separations such as the beneficiation of low grade Florida phosphate ores from 30-40% to 60-70% concentrations of calcium phosphate (BPL), and the separation of about 98% potassium chloride from sylvinite, a natural mixture of potassium and sodium chlorides. It is also used for bitumen separation from tar sand, removal of slate from coal, and removal of ink from repulped paper stock preparatory to the manufacture of recycled paper stock. More details of these separations are discussed in the relevant chapters. [Pg.395]


See other pages where Smelting of copper is mentioned: [Pg.140]    [Pg.162]    [Pg.481]    [Pg.396]    [Pg.327]    [Pg.353]    [Pg.771]    [Pg.306]    [Pg.1582]    [Pg.174]    [Pg.8]    [Pg.1628]    [Pg.159]    [Pg.1065]    [Pg.125]    [Pg.115]    [Pg.284]    [Pg.306]    [Pg.9]    [Pg.173]    [Pg.234]    [Pg.396]    [Pg.102]    [Pg.391]    [Pg.392]    [Pg.394]    [Pg.396]    [Pg.398]    [Pg.400]    [Pg.402]    [Pg.404]    [Pg.406]    [Pg.408]    [Pg.410]    [Pg.412]    [Pg.414]    [Pg.416]    [Pg.418]   
See also in sourсe #XX -- [ Pg.733 ]




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