Ores, resource extraction

Resources. World resources of silver are estimated to be about half a million tons. However, only about 250,000 metric tons are considered economically recoverable reserves. These are associated with ores of copper, gold, lead, and 2inc, and extraction depends on the economic recovery of those metals. Canada and the CIS vie for the greatest reserves of silver in the ground. 

The present description pertaining to copper refers to solvent extraction of copper at the Bluebird Mine, Miami. When the plant became operational in the first quarter of 1968 it used L1X 64, but L1X 64N was introduced in to its operation from late 1968. The ore consists of the oxidized minerals, chrysocolla and lesser amounts of azurite and malachite. A heap leaching process is adopted for this copper resource. Heap-leached copper solution is subjected to solvent extraction operation, the extractant being a solution of 7-8% L1X 64N incorporated in kerosene diluent. The extraction process flowsheet is shown in Figure 5.20. The extraction equilibrium diagram portrayed in Figure 5.21 (A) shows the condi-... 

When nonrenewable mineral resources are processed for metal extraction and the metals extracted are utilized in various ways and in diverse forms, they become potentially available for reclamation and recycling. Recycled metals produced by the extraction and refining of metallic wastes are known as secondary metals, whereas metals produced from primary ores are termed primary metals. A classification of recyclable metalliferous resources such... 

Besides the conventional uranium resources, there are also the so-called unconventional uranium resources , which are defined as deposits with very low uranium content, from which uranium is typically only recoverable as a minor by-product. These unconventional uranium resources are obtained from the extraction of phosphates, non-ferrous ores and carbonatites, as well as black schist and lignite. It has to be noted that the distinction between conventional and unconventional resources is not entirely clear cut, but is, instead, somewhat transitional. 

Coal combustion provides a substantial fraction of world energy production, both thermal and electrical. In addition, coal and its semi-processed derivative, coke, are cheap chemical reductants essential to the extraction of a variety of metals from their ores (e.g., Fe, Mn, Cu). The market for coal is likely to increase over the next decade only slowly in developed countries but more rapidly in developing countries with suitable domestic resources (e.g., China, India). 

The system for classification and disposal of hazardous chemical waste developed by EPA under RCRA does not apply to all wastes that contain hazardous chemicals. For example, wastes that contain dioxins, polychlorinated biphenyls (PCBs), or asbestos are regulated under the Toxic Substances Control Act (TSCA). In addition, the current definition of hazardous waste in 40 CFR Part 261 specifically excludes many wastes that contain hazardous chemicals from regulation under RCRA, including certain wastes produced by extraction, beneficiation, and processing of various ores and minerals or exploration, development, and use of energy resources. Thus, the waste classification system is not comprehensive, because many potentially important wastes that contain hazardous chemicals are excluded, and it is not based primarily on considerations of risks posed by wastes, because the exclusions are based on the source of the waste rather than the potential risk. 

EPA. 1995d. U.S. Environmental Protection Agency. Technical resource document, extraction and beneficiation of ores and minerals. EPA 530-R-94-032, NTIS PB94-2008987. 

Smface minir is less expensive and safer than tm-dergromrd mining. About 90% of the rock and mineral resources mined in the United States and more than 60% of the nation s coal is produced by surface minir techniques. Coal mining accomrts for abotrt half of all sitr-face mining, extraction of sand, gravel, stone, and clay for another 35%, phosphate rock for about 5%, and all metallic ores, for abotrt 13%. 

Metals are important resources and have a wide range of applications. Metals are often extracted from ores. Once the ore is mined, the metals must be extracted, usually by chemical or electrolytic reduction. Pyrometallurgy uses high temperatures to convert ore into raw metals, while hydrometalluigy employs aqueous chemistry for the same purpose. The methods used depend on the metal and their contaminants. Most metals are obtained by hydrometallurgical processes such as aqueous acids or alkalis are predominantly used to dissolve the metal oxides, sulfides, or silicates. Electrowinning and solvent extraction are frequently used to recover and concentrate the metals. A limited number of high-temperature molten salts have also been used for the recovery of refractory metals, such as titanium and aluminum, from their ores... 

Depletion of resources [24] Non-sustainable raw material use Petroleum or ore extraction... 

Battery price is calculated on the basis of the material and manufacturing costs. The cost of the active materials is directly related to their availability. With the exception of Na-S, Fe-air, and a few other exploratory systems, all EV battery candidates are based on materials whch are either not too abundant worldwide, reside in diluted ores, or can be extracted viably only from ores located geographically in a few areas. The Imports may be subject to politically Induced shortages or stoppages, in analogy to the gasoline situation. In some cases, even the domestic resource utilization may become prohibitive because of the environmental impact. 

Though Finland lacked deposits of coal, oil and many minerals, it did possess natural resources suitable for chemical production. In the 1910s, a new, rich copper mine at Outokumpu was opened its ore contained sulphur pyrites, among other things. However, the most valuable resources for the chemical industry were timber and water power. Processing staple wood products gave the forest industries opportunities to extract various chemicals as byproducts. Hydroelectricity was a new energy source for the electrochemical industries at the time. 

Students are likely to have come across ideas about extraction of metals in history lessons. For example, iron has been used since prehistoric times and the start of the Iron Age in 2500bc when it was first extracted from its ore. In geography lessons, students will have discussed the abundance of natural resources such as ores and may have studied the blast furnace. 

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