A factitious article is prepared by calcining a mixture of colcothar and red ochre.
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Calcining temperatures 1000 – 1500 °C produce hard-burned magnesia, which has limited reactivity and calcining at lower temperature, (700–1000 °C) produces light-burned magnesia, a reactive form, also known as caustic calcined magnesia. Although some decomposition of the carbonate to oxide occurs at temperatures below 700 °C, the resulting materials appears to reabsorb carbon dioxide from the air.
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Zirconia is produced by calcining zirconium compounds, exploiting its high thermal stability.Ralph Nielsen "Zirconium and Zirconium Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim.
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He died suddenly the year later, and his son Josiah II quickly rechristened the ware "Bone china".Spode Museum Trust:The First Spode Period 1776-1833 Among his developments was to abandon Frye's procedure of calcining the bone together with some of the other raw body materials, instead calcining just the bone. Bone china quickly proved to be highly popular, leading to its production by other English pottery manufacturers.Karwatka, Dennis.
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Alba's seawater desalination plant was commissioned in 2001. It utilises waste heat from the calcining process to generate steam for the production and supply of 41,000 cubic metres per day of potable water.
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Ingham, p.28. Calcining was discontinued in 1926 following a shutdown during the general strike with the ore being shipped "raw" after that time. By early 1927 no ore was being shipped to Wrexham, the Hook Norton quarries having to seek customers elsewhere.
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It is prepared by hydrothermal reaction using tetrapropylammonium hydroxide followed by calcining to remove residual ammonium salts. The compound is notable in being ca. 33% porous. It is useful because the material contains (SiO)10 rings that allow sorption of hydrophobic molecules of diameter 0.6 nm.
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Flash reactors have enormous potential for replacing or assisting existing primary ore oxidation, reduction or other pre-treatment conditioning processes (e.g. calcining) in metal refinery. The simplicity and throughput of a flash reactor can provide a cost-effective solution to ease the use of existing, expensive rigorous processes.
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St John the Baptist's church, Grade I listed, has been in the care of the Churches Conservation Trust since the early 1970s. Recent evidence points to Wakerley's industrial history as an iron-smelting centre. Brick- built calcining kilns were used for reducing iron ore before transport to the Corby Steelworks.
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Sulfur (S) is a frequent contaminant in coal. It is also present in small quantities in many ores, but can be removed by calcining. Sulfur dissolves readily in both liquid and solid iron at the temperatures present in iron smelting. The effects of even small amounts of sulfur are immediate and serious.
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Limekiln State Park is a state park of California, United States, on the Big Sur coast. It contains four lime kilns from an 1887–1890 lime-calcining operation, plus a beach, redwood forest, and Limekiln Falls. It is located south of Lucia on State Route 1. The park was established in 1994.
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These contain a concentric internal cylinder. This gathers pre-heated air from the cooling zone, which is then used to pressurize the middle annular zone of the kiln. Air spreading outward from the pressurized zone causes counter-current flow upwards, and co-current flow downwards. This again produces a long, relatively cool calcining zone.
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Chamotte is made by calcining fire clay (Al2O3-SiO2) above . Its fusion point is and has low thermal expansion. It is the second cheapest sand, however it is still twice as expensive as silica. Its disadvantages are very coarse grains, which result in a poor surface finish, and it is limited to dry sand molding.
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In 1768 he described the preparation, by calcining oyster-shell with sulphur, of the phosphorescent material known as Canton's phosphorus. His investigations were carried on without any intermission of his work as a schoolmaster. He died in London aged 53 of dropsy. He was the recipient of letters from Thomas Bayes, which were then published by the Royal Society.
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In June 1931 Brymbo went into receivership. In the late 1930s the Hook Norton quarries were leased by Mr Harmar-BrownIngham, p.30. but operations were on a small scale, only Park Farm Quarry being worked, often for only one day a week. The newest kiln was used, to dry the ore but not for calcining.
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With Thomas Sterry Hunt, Douglas was involved with many experiments in the hydrometallurgy of coppers and devised what is known as the "Hunt-Douglas" process (first patented 1869) for extracting copper from its ores. Douglas was also the inventor of several other improvements in the mining industry, consisting of the invention for calcining ores (1884), a furnace for calcining ores (1898), a process for extracting copper from cupriferous nickel ore (1892), a process for separating and recovering copper (1896), and an improved smelting furnace in 1897. During the early 1870s, he traveled to copper mines in Chile and Ore Knob, North Carolina to introduce the Hunt & Douglas process. In 1874, he introduced an improvement on the Hunt-Douglas process at J. Oscar Stewart's quartz mill in Georgetown, Colorado to also recover silver.
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Natural cements were frequently used in stucco mixes during the 1820s. The popularisation of Portland cement changed the composition of stucco, as well as mortar, to a harder material. The development of artificial cements had started early in the 19th century. In 1811, James Frost took out a patent for an artificial cement obtained by lightly calcining ground chalk and clay together.
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At high temperatures MgCO3 decomposes to magnesium oxide and carbon dioxide. This process is important in the production of magnesium oxide. This process is called calcining: :MgCO3 → MgO + CO2 (ΔH = +118 kJ/mol) The decomposition temperature is given as 350 °C (662 °F). However, calcination to the oxide is generally not considered complete below 900 °C due to interfering readsorption of liberated carbon dioxide.
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In metallurgy, refining consists of purifying an impure metal. It is to be distinguished from other processes such as smelting and calcining in that those two involve a chemical change to the raw material, whereas in refining, the final material is usually identical chemically to the original one, only it is purer. The processes used are of many types, including pyrometallurgical and hydrometallurgical techniques.
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Ellingham diagram for high temperature oxidation Pyrometallurgy involves high temperature processes where chemical reactions take place among gases, solids, and molten materials. Solids containing valuable metals are treated to form intermediate compounds for further processing or converted into their elemental or metallic state. Pyrometallurgical processes that involve gases and solids are typified by calcining and roasting operations. Processes that produce molten products are collectively referred to as smelting operations.
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The primary use of magnesium carbonate is the production of magnesium oxide by calcining. Magnesite and dolomite minerals are used to produce refractory bricks. MgCO3 is also used in flooring, fireproofing, fire extinguishing compositions, cosmetics, dusting powder, and toothpaste. Other applications are as filler material, smoke suppressant in plastics, a reinforcing agent in neoprene rubber, a drying agent, a laxative to loosen the bowels, and colour retention in foods.
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MnO occurs in nature as the rare mineral manganosite. Commercially it is prepared by reduction of MnO2 with hydrogen, carbon monoxide or methane, e.g.: :MnO2 \+ H2 → MnO + H2O :MnO2 \+ CO → MnO + CO2 MnO can also be prepared by decarbonation of the carbonate:W.H. McCarroll (1994) Oxides- Solid State Chemistry, Encyclopedia of Inorganic Chemistry Ed. R. Bruce King, John Wiley & Sons :MnCO3 → MnO + CO2 This calcining process is conducted anaerobically, lest Mn2O3 form.
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ALMO Process Technology Inc. is the North American branch of the ALLGAIER Group which is located in North America (Cincinnati, OH). Combining the names of the brands Allgaier and Mogensen, ALMO now represents the Process Technology division of the ALLGAIER Group in the USA and Canada. ALMO Process Technology is active in the areas of Washing, Drying, Cooling, Cleaning, Sorting, Screening, Calcining, Dispersion drying, Biomass drying, and Sizing.
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From 1897 ore was sold to Brymbo (who paid 1/6 per ton) and taken to their Hook Norton calcining plant. Being a farmer, Henry Baker required that when the quarrymen removed the overburden, topsoil and subsoil were segregated and replaced in sequence when the ore had been removed. Other ironstone quarries did not take this care when replacing the overburden with the result that the restored ground was poor for agricultural use.
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Magnesium oxide is produced by the calcination of magnesium carbonate or magnesium hydroxide. The latter is obtained by the treatment of magnesium chloride solutions, typically seawater, with lime. :Mg2+ \+ Ca(OH)2 → Mg(OH)2 \+ Ca2+ Calcining at different temperatures produces magnesium oxide of different reactivity. High temperatures 1500 – 2000 °C diminish the available surface area and produces dead-burned (often called dead burnt) magnesia, an unreactive form used as a refractory.
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Affiliated East-West Press Private Limited. pp. 131,132. . The hearths may be individually heated and the number, temperature, rotation rate and size of each hearth determines the residence time and conditions for the calcining powder in order to achieve the desired final properties. The individual hearths are lined with refractory brick, and the rabble arms are typically a force cooled metal alloy. The entire structure is enclosed in a cylindrical brick-lined steel shell.
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The French Engineer Louis Vicat in 1812–1813 experimented with calcining synthetic mixtures of limestone and clay, a product he introduced in 1818. In 1822, in the UK, James Frost patented (another?) process, similar to Vicat's, producing what he called "British cement". Portland cement, patented in 1824 by Joseph Aspdin, was called so because it was supposed to resemble Portland stone. Aspdinís son William, and later Isaac Johnson, improved the production process.
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The carbonate is insoluble in water but, like most carbonates, hydrolyses upon treatment with acids to give water-soluble salts. Manganese carbonate decomposes with release of carbon dioxide, i.e. calcining, at 200 °C to give MnO1.88: :MnCO3 \+ 0.44 O2 → MnO1.8 \+ CO2 This method is sometimes employed in the production of manganese dioxide, which is used in dry-cell batteries and for ferrites. Manganese carbonate is widely used as an additive to plant fertilizers to cure manganese deficient crops.
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The Clean Air Interstate Rule also requested that the power plants install new scrubbers (industrial pollution control devices) to remove sulfur dioxide present in the output waste gas. Scrubbers use the technique of flue-gas desulfurization (FGD), which produces synthetic gypsum as a usable by-product. In response to the new supply of this raw material, the gypsum board market was predicted to shift significantly. However, issues such as mercury release during calcining need to be resolved.
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This refers to lead glass as "Jewish glass", perhaps indicating its transmission to Europe. A manuscript preserved in the Biblioteca Marciana, Venice, describes the use of lead oxide in enamels and includes recipes for calcining lead to form the oxide. Lead glass was ideally suited for enamelling vessels and windows owing to its lower working temperature than the forest glass of the body. Antonio Neri devoted book four of his L’Arte Vetraria ("The Art of Glass-making", 1612) to lead glass.
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A sketch of a Herreshoff multiple-hearth furnace A multiple hearth furnace also known as a vertical calciner, is used for continuous preparation and calcining of materials. The multiple hearth furnace consists of several circular hearths or kilns superimposed on each other. Material is fed from the top and is moved by action of rotating "rabble arms", and the revolving mechanical rabbles attached to the arms move over the surface of each hearth to continuously shift the ore. The arms are attached to a rotating central shaft that passes through the center of the roaster.
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Portland cement clinker is made by heating, in a cement kiln, a mixture of raw materials to a calcining temperature of above and then a fusion temperature, which is about for modern cements, to sinter the materials into clinker. The materials in cement clinker are alite, belite, tri-calcium aluminate, and tetra-calcium alumino ferrite. The aluminium, iron, and magnesium oxides are present as a flux allowing the calcium silicates to form at a lower temperature,McArthur, Hugh, and Duncan Spalding. Engineering materials science: properties, uses, degradation and remediation.
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Beryllium oxide can be prepared by calcining (roasting) beryllium carbonate, dehydrating beryllium hydroxide, or igniting metallic beryllium: :BeCO3 → BeO + CO2 :Be(OH)2 → BeO + H2O :2 Be + O2 → 2 BeO Igniting beryllium in air gives a mixture of BeO and the nitride Be3N2. Unlike the oxides formed by the other Group 2 elements (alkaline earth metals), beryllium oxide is amphoteric rather than basic. Beryllium oxide formed at high temperatures (>800 °C) is inert, but dissolves easily in hot aqueous ammonium bifluoride (NH4HF2) or a solution of hot concentrated sulfuric acid (H2SO4) and ammonium sulfate ((NH4)2SO4).
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The dead tree still contains the substantial form of the wood, so clearly that form must have been there even when the tree was alive. Paul’s experimental approach is to decompose metals into other materials, then attempt to recombine those materials into the metal again. If the sulfur-mercury theory is correct, you can decompose metals into the four elements, but when attempting to recombine the elements, there is no reason for the elements to recombine into any one particular metal. Paul writes that he successfully recreated the same metal after a process of calcining, dissolving, subliming, and lastly reducing metals.
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MgO(s)+ CO2(g) (dolomite calcining) : (Fe,Si)(s) + 2 MgO(s) ↔ Fe(s) + SiO2(s) + 2 Mg(g) : CaO + SiO2 → CaSiO3 The Pidgeon process is a batch process in which finely powdered calcined dolomite and ferrosilicon are mixed, briquetted, and charged in retorts made of nickel-chrome-steel alloy. The hot reaction zone portion of the retort is either gas fired, coal fired, or electrically heated in a furnace, while the condensing section equipped with removable baffles extends from the furnace and is water-cooled. Due to distillation, very high purity magnesium crowns are produced, which are then remelted and cast into ingots.
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High-reactivity metakaolin (HRM) is a highly processed reactive aluminosilicate pozzolan, a finely-divided material that reacts with slaked lime at ordinary temperature and in the presence of moisture to form a strong slow-hardening cement. It is formed by calcining purified kaolinite, generally between 650–700 °C in an externally fired rotary kiln. It is also reported that HRM is responsible for acceleration in the hydration of ordinary portland cement (OPC), and its major impact is seen within 24 hours. It also reduces the deterioration of concrete by Alkali Silica Reaction (ASR), particularly useful when using recycled crushed glass or glass fines as aggregate.
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At Dale Head is the source of the River Seven which flows down the valley to join the River Rye at Little Habton near Malton. At its southern end, Rosedale is squeezed between Spaunton Moor and Hartoft Rigg, where the river flows out through Forestry Commission woodland before passing the village of Cropton to reach the plains of the Vale of Pickering. View towards Rosedale Abbey Ruins of calcining kilns near Rosedale East Ironstone Mine Rosedale has only a small number of people involved in farming. The majority of homes are bought as second homes and as such the permanent local population has been significantly reduced.
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Heating the carbonate, proceeds in a typical way for calcining, except that the material is partially oxidized: : 6 CoCO3 \+ O2 → 2 Co3O4 \+ 6 CO2 The resulting Co3O4 converts reversibly to CoO at high temperatures.G.A. El- Shobaky, A.S. Ahmad, A.N. Al-Noaimi and H.G. El-Shobaky Journal of Thermal Analysis and Calorimetry 1996, Volume 46, Number 6 , pp.1801-1808. online abstract Like most transition metal carbonates, cobalt carbonate is insoluble in water, but is readily attacked by mineral acids: :CoCO3 \+ 2 HCl + 5 H2O → [Co(H2O)6]Cl2 \+ CO2 It is used to prepare many coordination complexes. The reaction of cobalt(II) carbonate and acetylacetone in the presence of hydrogen peroxide gives tris(acetylacetonato)cobalt(III).
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In January 1883 The Cornishman newspaper reported that an estimated £42,000 worth of tin went down the river and many thousands of pounds yearly are made by ″the squatters″ who set up machinery and harvest the waste products of the mines. Within Tuckingmill Valley Park is a small island containing the remains of a chimney stack, brick scrubber building and collapsed flue. The buildings (circa 1905) are associated with the production of arsenic which was a valuable resource for Cornish tin and copper mines when production of the metals was declining and the mines were closing. More efficient calcining furnaces were built and the gases fed through convoluted labyrinths where they cooled and condensed on the flue walls.
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Two of the furnaces View of the iron works, 1800 The land on which the Ironworks resides was at one time the property of Lord Abergavenny and was leased in 1787 by three Midlands businessmen, Thomas Hill, his brother-in-law Thomas Hopkins and Benjamin Pratt. Work constructing the Ironworks began immediately and included several "luxury" cottages. Blaenavon Ironworks was the first to be designed as a multi-furnace site from the outset, with three furnaces, calcining kilns, cottages, and a company shop. Archdeacon Coxe visited Blaenavon during 1798–99 and enthusiastically described the small town as an opulent and increasing establishment, which was ...surrounded with heaps of ore, coal and limestone...Coxe, W. (1801) An Historical Tour of Monmouthshire.
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Beneficiation process (separating ore into mineral and gangue) employed and either exporting it as raw material (magnesium carbonate), or calcination, or deadburning follows for caustic calcined magnesia (reactive material) or deadburned magnesia (sintered magnesia) (a non-reactive material), respectively in order to make raw magnesite suitable for various uses. Magnesium carbonate (MgCO3) (An inorganic salt, a white solid) is used for the production of magnesium oxide (MgO) by calcining. MgCO3 is used at industrial applications, agricultural industries, the pulp and paper industry, the pharmaceutical industry and in the manufacture of rubber (as reinforcing agent in neoprene rubber), paints and plastics (as smoke suppressant), flooring, fireproofing, fire extinguishing compositions, dusting powder, cosmetics and toothpaste, antacid, additive in table salt). In addition, as filler material, a drying agent, a laxative to loosen the bowels, (Milk of Magnesia) and color retention in foods.
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Carbon dioxide can be obtained by distillation from air, but the method is inefficient. Industrially, carbon dioxide is predominantly an unrecovered waste product, produced by several methods which may be practiced at various scales. The combustion of all carbon-based fuels, such as methane (natural gas), petroleum distillates (gasoline, diesel, kerosene, propane), coal, wood and generic organic matter produces carbon dioxide and, except in the case of pure carbon, water. As an example, the chemical reaction between methane and oxygen: : + 2 → + 2 It is produced by thermal decomposition of limestone, by heating (calcining) at about , in the manufacture of quicklime (calcium oxide, ), a compound that has many industrial uses: : → + Iron is reduced from its oxides with coke in a blast furnace, producing pig iron and carbon dioxide: Carbon dioxide is a byproduct of the industrial production of hydrogen by steam reforming and the water gas shift reaction in ammonia production.
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NiCO3 adopts a structure like calcite, consisting of nickel in an octahedral coordination geometry. Nickel carbonates are hydrolyzed upon contact with aqueous acids to give solutions containing the ion [Ni(H2O)6]2+, liberating water and carbon dioxide in the process. Calcining (heating to drive off CO2 and water) of these carbonates gives nickel oxide: :NiCO3 → NiO + CO2 The nature of the resulting oxide depends on the nature of the precursor. The oxide obtained from the basic carbonate is often most useful for catalysis. Basic nickel carbonate can be made by treating solutions of nickel sulfate with sodium carbonate: :4 Ni2+ \+ CO32− \+ 6 OH− \+ 4 H2O → Ni4CO3(OH)6(H2O)4 The hydrated carbonate has been prepared by electrolytic oxidation of nickel in the presence of carbon dioxide:Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. p. 1557.
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' The whole tract may present a > pleasant aspect in the fresh time of the year, when the ground is covered > with herbage; when the trees are in their green leaf, and the glens are > enlivened by running streams. Unfortunately, we entered it too late in the > season The herbage was parched; the foliage of the scrubby forests was > withered; the whole woodland prospect, as far as the eye could reach, had a > brown and arid hue. The fires made on the prairies by the Indian hunters, > had frequently penetrated these forests, sweeping in light transient flames > along the dry grass, scorching and calcining the lower twigs and branches of > the trees, and leaving them black and hard, so as to tear the flesh of man > and horse that had to scramble through them. I shall not easily forget the > mortal toil, and the vexations of flesh and spirit, that we underwent > occasionally, in our wanderings through the Cross Timber.
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In 1899, the American Borax Company bought mining claims at Lead Mountain, about four miles west of Calico, to mine boric acid and plotted to build a railroad to reach Daggett across the river where they had their processing plants. American Borax agreed with the Waterloo Mining Company and D.D. Connell (who by then was also leasing the line from Waterloo Mining along with fellow miner Marcus Pluth, to transport the last of the ore from Waterloo Mine in 1899) to reserve running rights on the line to allow their trains to use the same track in between the junctions going towards Calico and the borax mine at Lead Mountain (named "Columbia"). They had also leased the line's first locomotive "Uncle Dan," to operate the borax trains outgoing from Lead Mountain. The line was extended from the mill branch at Elephant Mountain to cross the Mojave River on a Pratt through truss bridge before pulling into the Columbia Mill on the other side of the river, where the calcining plants were located.
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