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12.3. Equipment for leaching. Three distinct processes are typically involved in leaching operations: (a) dissolving the soluble constituent; (b) separating the solution, so formed, from the insoluble solid residue; and (c) washing the solid residue in order to remove unwanted soluble matter or to obtain as much of the soluble material as possible …
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The pretreatment is usually carried out by roasting at ~650 °C, leaching in a dilute inorganic acid or alkali solution, or combining of roasting and leaching process, in order to remove organics and impurities in the ore (Trasorras et al., 2016, BGS, 2011a, Zhang and Zhao, 2005). 3.2. Secondary resources
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The separation and extration of tin and tungsten from wolframite – scheelite mixed ore with high tin content is urgently needed given the increasingly exhaustion of the high-grade tungsten ore ...
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Kinetics equation (1–4) shows that temperature affects the leaching process; therefore, to improve the leaching process, sulfuric-phosphoric acid can be …
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There are many valuable metals such as W, Sn, Mo and Bi in residue abandoned in the wet-metallurgical process of wolframite ores, recovering the valuable metals can get good social and economic benefits. But the size of WO3, Sn, Bi in the sample is +37μm, 37~76μm and 19~76μm respectively, and Mo is relative scattering. According to the …
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Tungsten ore decomposition process comes in two types: alkaline process and acid process. Alkaline Process. These include soda sintering, soda high pressure leaching, and sodium hydroxide leaching. 1. Soda sintering: scheelite concentrate and wolframite concentrate are processed through different chemical reactions.
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The leaching efficiency of tungsten was calculated using Eq. (1): (1) η 1 = c 1 × v 1 m 1 × w 1 × 100 % where m 1 is the mass of the ore (g), w 1 is the mass fraction of tungsten in the ore, c 1 is the concentration of tungsten in the leachate (g/L), and v 1 is the volume of leachate (L). The extraction efficiency of tungsten from the ...
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Nanostructured scheelite (CaWO 4) was synthesized by calcination in air of enriched wolframite (Fe 1−x Mn x WO 4) ore and calcium carbonate (CaCO 3).The effects of process parameters such as milling conditions of the solid reactants, calcination in flowing or static air, and use of stoichiometric excess of calcium carbonate on …
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1. Wolframite Ore Crushing The tungsten ore is successfully crushed to below 15 mm through coarse crushing with a jaw crusher and fine crushing with an impact crusher after mining. 2. Wolframite Ore Grinding Wolframite is brittle and easily crushed, leading to the production of tungsten slimes during the crushing and grinding process.
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1. Introduction. Scheelite can be processed by carbonate autoclaving process [1], [2], [3] and hydrochloric acid leaching process [4], [5].Prior to the early 1980s, it was reported in literature that scheelite could not be decomposed with sodium hydroxide under commercial conditions [6].However, through in-depth study on caustic …
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An overview of the composition of wolframite ores of the Akchatau deposit and the technologies for processing concentrates using NaOH and Na2CO3 by hydro- and pyrometallurgical methods is given ...
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Tungsten is one of the critical minerals with wide applications. The most common tungsten minerals are wolframite (Fe,Mn)WO 4 and scheelite CaWO 4 [1,2,3].Leaching of the tungsten minerals is the key process in production of the final products.
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To decrease the leaching rate of tin in the alkaline decomposition process, Wang and Dong (2015) used the oxidizing roasting method to treat the tin-containing wolframite-scheelite mixed ore by adding calclime. Nevertheless, experimental results indicated that the sodium tungstate solution still has the tin content of 1.05% that must …
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Since the amount of leaching agent is critical to the process and since it represents one of the largest cost items, characteristics of the ore are relevant to the extraction process . The metal recovery from WEEE through the leaching process typically requires oxidative leaching [5, 6].
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Physicochemical and mineralogical characteristics of an alkali leaching residue of wolframite were studied by XRD, SEM−EDS, chemical phase analysis, …
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The observation of the surface morphology of product particles showed that the wolframite decomposition is a process in which the leaching agent eroded …
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The soda ash roast–aqueous leach process was successfully tested on a low grade wolframite concentrate (7% and 24% WO 3) by Subramanian et al. [3] and on a scheelite concentrate (65% WO 3) by Paramguru et al. [4].However, no studies have been reported on the applicability of this method for recovering tungsten values from …
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Solvent extraction of wolframite ore leach liquor containing 630.3 mg/L W, 23.1 mg/L Fe and 0.8 mg/L Mn was carried out by 0.15 mol/L ALIQUAT 336 in kerosene at 27 ± 2 °C for 25 min contact time. ... Guiqing Z, Wenjuan G, Liansheng X, Qixiu Z (2016) A novel process for tungsten hydrometallurgy based on direct solvent extraction in alkaline ...
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Section snippets Materials and reagents. The wolframite concentrate was provided by Jiangxi Tungsten Group Co., Ltd., China. The concentrate contains WO 3 69.50%, Fe 11.12%, and Mn 6.56% as the main compositions as presented in Table 1. The X-ray diffraction (XRD) pattern of the concentrate (Fig. 1) shows that it is with high …
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Beneficiation of Microsize Wolframite by Flocculation and Gravity Separation. Materials, Wolframite was obtained from Jiangxi, physically purified and ground in porcelain mill, getting -10 µm microsize by a sedimentation.The sample was assayed for 71.57% WO2. The quartz sample (-19 µm) was purchased from changsha …
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Experimental laboratory work on leaching of low-grade wolframite concentrate has shown that the dissolution of tungsten with a high extraction (90%) can only be reached after mechanical treatment ...
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The results show that the leaching process can be described by Avrami model, with the chemical reaction as the controlling step, the model parameter is determined to be 0.83, the apparent ...
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A beneficiation study indicated that beneficiating wolframite-scheelite mixed ore with approximately 40% WO 3 content can guarantee a higher metal recovery ratio, ... In the leaching process, tungsten is leached into lixivium, and a large proportion of tin remains in the decomposition residue that is recovered in the subsequent processing. …
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Acid digestion of tungsten concentrates has attracted more and more attention in recent years, sustainable extraction of tungsten from acid digestion product of tungsten concentrates to obtain (NH 4) 2 WO 4 solution with low impurity content is the key for ammonium paratungstate production. In this work, a process of extracting tungsten …
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The first step in the production of tungsten is to enrich tungsten from two minerals wolframite ((Fe, Mn)WO 4) and scheelite (CaWO 4) through the leaching process.The leaching residue usually contains a certain amount (2–5 wt%) of WO 3 which is higher than that in the tungsten ore (generally less than 1 wt%). In addition, the …
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Bioleaching process and commercial bioheap leaching plants: (a) schematic representation of the bioheap leaching process, (b) bioleaching plant in Zijinshan copper mine, China (Renman et al. 2006), (c) bioheap leaching plant in Talvivara mining company, Finland (Riekkola-Vanhanen 2010) and (d) bioheap leaching plant in …
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With the effect of added Ca (OH) 2 in the grinding process, the wolframite concentrates with greater ferberite content were found to be converted into scheelite, …
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Wolframite could be converted into scheelite by adding Ca(OH)2 in the mechanical activation, significantly improving the leaching efficiency of wolframite. This …
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In this study, the metabolism of a hydrometallurgical process for tungsten extracting from wolframite was studied through substance flow analysis. The mass balance accounts, substance flow charts of tungsten and arsenic were established to evaluate the metabolism efficiency of the investigated system. The results showed that, …
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The wolframite concentrate was provided by Jiangxi Tungsten Group Co., Ltd., China. The concentrate contains WO 3 69.50%, Fe 11.12%, and Mn 6.56% as the main compositions as presented in Table 1.The X-ray diffraction (XRD) pattern of the concentrate (Fig. 1) shows that it is with high content of wolframite [(Fe,Mn)WO 4] and …
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