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Bottom-blown Oxygen Converter
The Bottom-blown Oxygen Converter or BBOC is a smelting furnace developed by the staff at Britannia Refined Metals Limited (“BRM”), a British subsidiary of MIM Holdings Limited (which is now part of the Glencore group of companies). The furnace is currently marketed by Glencore Technology. It is a sealed, flat-bottomed furnace mounted on a tilting frame that is used in the recovery of precious metals. A key feature is the use of a shrouded lance to inject oxygen through the bottom of the furnace, directly into the precious metals contained in the furnace, to oxidize base metals or other impurities as part of their removal as slag.J M Floyd, “Submerged bath smelting applied to the non-ferrous metal industry,” in: ''The Paul E. Queneau International Symposium, Extractive Metallurgy of Copper, Nickel and Cobalt, Volume I: Fundamental Aspects'', Eds R G Reddy and R N Weizenbach (The Minerals, Metals and Materials Society: Warrendale, Pennsylvania, 1993), 473–488. Introductio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BBOC And Frame
The ''Bulletin of the British Ornithologists' Club'' is an ornithological journal published by the British Ornithologists' Club (BOC). It is cited as ''Bull. B. O. C.'' Many descriptions of birds new to science have been published in the bulletin. The journal was first published in 1892. It is published in four quarterly issues. from March 2017 (Vol. 137 No. 1), it became an online-only, open access, journal, giving as the reasons for the change: Since 2004, the journal's honorary editor has been Guy Kirwan. List of editors List of Bulletin Editors with dates of tenure * Richard Bowdler Sharpe 1892–1904 * W. R. Ogilvie-Grant 1904–1914 * David Armitage Bannerman 1914–1915 * D. Seth-Smith 1915–1920 * Percy R. Lowe 1920–1925 * Norman B. Kinnear 1925–1930 * G. Carmichael Low 1930–1935 and 1940–1945 * C. H. B. Grant 1935–1940 and 1947–1952 * W. P. C. Tenison 1945–1947 * J. G. Harrison 1952–1961 * J.J. Yealland 1962–1969 * C.W. Benson 1969 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noble Metal
A noble metal is ordinarily regarded as a metallic chemical element that is generally resistant to corrosion and is usually found in nature in its raw form. Gold, platinum, and the other platinum group metals (ruthenium, rhodium, palladium, osmium, iridium) are most often so classified. Silver, copper and mercury are sometimes included as noble metals, however less often as each of these usually occurs in nature combined with sulfur. In more specialized fields of study and applications the number of elements counted as noble metals can be smaller or larger. In physics, there are only three noble metals: copper, silver and gold. In dentistry, silver is not always counted as a noble metal since it is subject to corrosion when present in the mouth. In chemistry, the term noble metal is sometimes applied more broadly to any metallic or semimetallic element that does not react with a weak acid and give off hydrogen gas in the process. This broader set includes copper, mercury, tech ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper Extraction Techniques
Copper extraction refers to the methods used to obtain copper from its ores. The conversion of copper consists of a series of physical and electrochemical processes. Methods have evolved and vary with country depending on the ore source, local environmental regulations, and other factors. As in all mining operations, the ore must usually be beneficiated (concentrated). The processing techniques depend on the nature of the ore. If the ore is primarily sulfide copper minerals (such as chalcopyrite), the ore is crushed and ground to liberate the valuable minerals from the waste ('gangue') minerals. It is then concentrated using mineral flotation. The concentrate is typically sold to distant smelters, although some large mines have smelters located nearby. Such colocation of mines and smelters was more typical in the 19th and early 20th centuries, when smaller smelters could be economic. The sulfide concentrates are typically smelted in such furnaces as the Outokumpu or Inc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrowinning
Electrowinning, also called electroextraction, is the electrodeposition of metals from their ores that have been put in solution via a process commonly referred to as leaching. Electrorefining uses a similar process to remove impurities from a metal. Both processes use electroplating on a large scale and are important techniques for the economical and straightforward purification of non-ferrous metals. The resulting metals are said to be ''electrowon''. In electrowinning, an electrical current is passed from an inert anode (oxidation, made out of lead (Pb)) through a ''leach'' solution containing the dissolved metal ions so that the metal is recovered as it is deposited in an electroplating process onto the cathode (reduction, stainless steel, aluminium (Al), titanium (Ti)). In electrorefining, the anode consists of the impure metal (e.g., copper) to be refined. The impure metallic anode is oxidized and the metal dissolves into solution. The metal ions migrate through the acidic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operating Temperature
An operating temperature is the allowable temperature range of the local ambient environment at which an electrical or mechanical device operates. The device will operate effectively within a specified temperature range which varies based on the device function and application context, and ranges from the minimum operating temperature to the maximum operating temperature (or peak operating temperature). Outside this range of safe operating temperatures the device may fail. It is one component of reliability engineering. Similarly, biological systems have a viable temperature range, which might be referred to as an "operating temperature". Ranges Most devices are manufactured in several temperature grades. Broadly accepted grades are: *Commercial: 0 ° to 70 °C *Industrial: −40 ° to 85 °C *Military: −55 ° to 125 °C Nevertheless, each manufacturer defines its own temperature grades so designers must pay close attention to actual datasheet spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nyrstar
Nyrstar is a global multi-metals business, with a market leading position in zinc and lead and growing positions in other base and precious metals, such as copper, gold and silver. Nyrstar has mining and smelting operations located in Europe, North America and Australia. Nyrstar was created in 2007 by combining the zinc smelting and alloying operations of Zinifex (an Australian mining company, now merged with Oxiana Limited to form OZ Minerals) and Umicore (a Belgian materials technology company). It is incorporated in Belgium and has its corporate office in Switzerland. Nyrstar is listed on Euronext Brussels. Nyrstar was acquired by Trafigura in 2019. Operations Nyrstar has 4 mining operations located in North America. Nyrstar has 6 smelters (in Australia, Belgium, France, Netherlands, and the United States) and 1 fumer in Norway. Trafigura Trafigura Group Pte. Ltd. is a Singaporean-based Swiss multinational commodity trading company founded in 1993 that trades in base meta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rand Refinery
Rand Refinery (Pty) Limited is the largest integrated single-site precious metals refining and smelting complex in the world. It was established in 1920 to refine gold within South Africa which until that time had been refined in London. History It was established in 1920 in Germiston, South Africa, by the Chamber of Mines of South Africa to refine all the gold produced by South Africa's gold mines instead of in London. As of 1919, the Bank of England would receive consignments of raw gold from the producers and issue it to individual refineries, refined and then returned to the Bank for sale, and the hope was that after the Rand Refinery was built, the gold industry would still be financed in London and that the refined gold would be sold in the latter. On 27 November 1920, Rand Refinery Ltd was registered as a private company, the capital raised from shares of gold mining companies that were members of the Chamber of Mines. Building of the facilities commenced in August 1920. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dross
Dross is a mass of solid impurities floating on a molten metal or dispersed in the metal, such as in wrought iron. It forms on the surface of low- melting-point metals such as tin, lead, zinc or aluminium or alloys by oxidation of the metal. For higher melting point metals and alloys such as steel and silver, oxidized impurities melt and float making them easy to pour off. With wrought iron, hammering and later rolling remove some dross. With tin and lead the dross can be removed by adding sodium hydroxide pellets, which dissolve the oxides and form a slag. If floating, dross can also be skimmed off. Dross, as a solid, is distinguished from slag, which is a liquid. Dross product is not entirely waste material; for example, aluminium dross can be recycled and is also used in secondary steelmaking for slag deoxidation. Etymology and usage The term ''dross'' derives from the Old English word ''dros'', meaning the scum produced when smelting metals (extracting them from their ore ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc Oxide
Zinc oxide is an inorganic compound with the formula . It is a white powder that is insoluble in water. ZnO is used as an additive in numerous materials and products including cosmetics, food supplements, rubbers, plastics, ceramics, glass, cement, lubricants, paints, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, and first-aid tapes. Although it occurs naturally as the mineral zincite, most zinc oxide is produced synthetically. ZnO is a wide-band gap semiconductor of the II-VI semiconductor group. The native doping of the semiconductor due to oxygen vacancies or zinc interstitials is n-type. Other favorable properties include good transparency, high electron mobility, wide band gap, and strong room-temperature luminescence. Those properties make ZnO valuable for a variety of emerging applications: transparent electrodes in liquid crystal displays, energy-saving or heat-protecting windows, and electronics as thin-film transistors and lig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BBOC Operating Positions Vertical
The ''Bulletin of the British Ornithologists' Club'' is an ornithological journal published by the British Ornithologists' Club (BOC). It is cited as ''Bull. B. O. C.'' Many descriptions of birds new to science have been published in the bulletin. The journal was first published in 1892. It is published in four quarterly issues. from March 2017 (Vol. 137 No. 1), it became an online-only, open access, journal, giving as the reasons for the change: Since 2004, the journal's honorary editor has been Guy Kirwan. List of editors List of Bulletin Editors with dates of tenure * Richard Bowdler Sharpe 1892–1904 * W. R. Ogilvie-Grant 1904–1914 * David Armitage Bannerman 1914–1915 * D. Seth-Smith 1915–1920 * Percy R. Lowe 1920–1925 * Norman B. Kinnear 1925–1930 * G. Carmichael Low 1930–1935 and 1940–1945 * C. H. B. Grant 1935–1940 and 1947–1952 * W. P. C. Tenison 1945–1947 * J. G. Harrison 1952–1961 * J.J. Yealland 1962–1969 * C.W. Benson 1969 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead(II) Oxide
Lead(II) oxide, also called lead monoxide, is the inorganic compound with the molecular formula Pb O. PbO occurs in two polymorphs: litharge having a tetragonal crystal structure, and massicot having an orthorhombic crystal structure. Modern applications for PbO are mostly in lead-based industrial glass and industrial ceramics, including computer components. It is an amphoteric oxide. Types Lead oxide exists in two types: * Red tetragonal (α-PbO), obtained at lower temperatures than the β-PbO * Yellow orthorhombic (β-PbO), which is obtained temperatures higher than Synthesis PbO may be prepared by heating lead metal in air at approximately . At this temperature it is also the end product of decomposition of other oxides of lead in air: :PbO2->[] Pb12O19 ->[] Pb12O17 ->[] Pb3O4 ->[] PbO Thermal decomposition of lead(II) nitrate or lead carbonate, lead(II) carbonate also results in the formation of PbO: :2 → 2 PbO + 4 + : → PbO + PbO is produced ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Litharge
Litharge (from Greek lithargyros, lithos (stone) + argyros (silver) ''λιθάργυρος'') is one of the natural mineral forms of lead(II) oxide, PbO. Litharge is a secondary mineral which forms from the oxidation of galena ores. It forms as coatings and encrustations with internal tetragonal crystal structure. It is dimorphous with the orthorhombic form massicot. It forms soft (Mohs hardness of 2), red, greasy-appearing crusts with a very high specific gravity of 9.14–9.35. PbO may be prepared by heating lead metal in air at approximately 600 °C (lead melts at only 300 °C). At this temperature it is also the end product of heating of other lead oxides in air. This is often done with a set of bellows pumping air over molten lead and causing the oxidized product to slip or fall off the top into a receptacle, where it quickly solidifies in minute scales. :PbO2 –(293 °C)→ Pb12O19 –(351 °C)→ Pb12O17 –(375 °C)→ Pb3O4 –(605 °C)→ PbO Historical term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
