Copper refining wastes

Copper refining wastes containing Cr and Sb were added to cements and the rate of hydration was followed by DTA, TG, and DTG. There was a significant decrease in the amount of Ca(OH)2 in pastes hydrated with the copper refining waste, suggesting that it is a good retarder.I l... 

Zivica, V., Stabilization of Copper Refining Waste in Cement Matrix Using Thermal Analysis,/. Therm. Analysis, A6 6 -6 l (19%)... 

More than 90 percent of the tellurium produced in the United States is obtained as a by-product of the refining of copper. The waste materials left over from this process are treated to obtain pure tellurium. 

Most copper is processed using a combination of mining, concentrating, smelting, and refining, or by leaching waste and solvent... 

Production operations are subject to a number of regulations, including those imposed by the Resource Conservation and Recovery Act (RCRA),6 7 the Clean Water Act (CWA),8 and the Clean Air Act (CAA).9 A number of RCRA-listed hazardous wastes are produced during primary refining operations that require the heating of ores to remove impurities. Specific pretreatment standards under the CWA apply to the processes associated with copper and aluminum. Lastly, large amounts... 

Refining operations have two principal wastestreams, waste electrolyte and cathode and anode washwater. Spent electrolyte is normally recycled. A bleed stream is treated to reduce copper and impurity concentration. Varying degrees of treatment are necessary because of the differences in the anode copper. Anode impurities, including nickel, arsenic, and traces of antimony and bismuth, may be present in the effluent if the spent electrolyte bleed stream is discharged. Tables 3.14 and 3.15 present classical and toxic pollutant data for raw wastewater in this subcategory. 

Copper discharges to the global biosphere are due primarily to human activities, especially mining, smelting, and refining copper and the treatment and recycling of municipal and industrial wastes. Some copper compounds, especially copper sulfate, also contribute to environmental copper burdens because they are widely and intensively used in confined geographic areas to control nuisance species of aquatic plants and invertebrates, diseases of terrestrial crop plants, and ectoparasites of fish and livestock. 

The vendor states that MBS stabihzes heavy metals in soil, slndges, slag, ash, baghonse dnst, and sediment. Among the heavy metals treatable by the MBS process are arsenic, cad-minm, chrominm, copper, lead, mercnry, nickel, silver, and zinc. MBS technology is applicable in the following indnstries primary and secondary smelters, battery mannfactnrers and recyclers, ferrons and nonferrons fonndries, mnnicipal solid waste incinerators, anto and metal scrap recyclers, electronic mannfactnrers, electroplaters, ceramic prodnct mannfactnrers, and mineral refiners and processors. 

Nano-photosynthesis can produce sugar and starch for food and further synthesis of cellulose can produce paper and wood to avoid clear-cutting forests. Carbon retrieved from the atmosphere and recycled from existing wastes by MNT will be used to make carbon nano-tubes, with superior properties to steel. Carbon will be the most common structural and functional element for a MNT-based civilization [32,33]. A carbon-based MNT material production model is conceptualized as in Fig. 9. If there is a specific need for metal, a nano-factory with trillions of nano-assemblers will synthesize steel, copper, and alloys in order to skip mining and refining [32,33]. Therefore, industrial wastewater, hazardous wastes and air pollution will all vanish. 

Manufacture. Copper scrap is added to the waste solution during the refining of copper by electricity. The liquid is also heated by blowing air into it and filtered. The filtrate is concentrated, and the copper sulphate crystallizes out. Copper scrap can be added to sulphuric acid which contains a small amount of nitric acid, or an excess of sulphur is added to heated copper to form copper sulphide, which is heated further to oxidize it until it becomes copper sulphate. 

One should point out that bismuth content in the Earth s crust is one-fifth as high as that of lead [19], However, deposits of bismuth with high content of about 5-25% are very rare and locate in Bolivia, Tasmania, Peru and Spain. That is why 90% of world bismuth has been manufactured from the wastes of lead-refining, copper-smelting and tinning plants. 

Because of the high temperature corrosion resistance and thermal stability exhibited by magnesium-chromium oxide refractories in copper smelting, converting and fire refining furnaces, little research has been conducted on other refractory families. However, the concern for hexavalent chromium (Cr ) as a potentially hazardous waste in spent refractories from copper production furnaces has prompted the recognition that a more environmentally acceptable material is needed for the copper industry. 

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