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Rapid identification of an effective bauxite gas reservoir by …

The Al-bearing rock series can be divided into seven types (Fig. 5) on the basis of the contents of silicon oxide (SiO 2), aluminium + titanium oxide (Al 2 O 3 + TiO …

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Removal of silicates from gibbsite-bauxite ore by using …

The increasing of collector dosage at pH 10 gives a good result on Al 2 O 3 content is 62% and SiO 2 is 29.4% with 50.44% recovery of Al 2 O 3 obtained at dosage of collector at 500 g/ton. The Al 2 O 3 ontent which is higher in conditions without the addition of depressant is 66.8% while SiO 2 in 23.5%. While for the size fraction variation, it ...

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Beneficiation of bauxite ores

(4.1) 3 Al 2 SiO 5 (OH) 4 + 18 NaOH → 6 Na 2 SiO 3 + 6 NaAl (OH) 4 + 3 H 2 O (4.2) ... The entire work of overburden removal, extraction of bauxite and loading of bauxite onto trucks is conducted manually and the bauxite is transported to respective railway siding or plants by road. 4.4.2. Semimechanized mines.

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Multi-element comprehensive utilization of high-silicon …

High-silicon bauxite, as a potential resource for the industrial production of alumina, contains large amounts of Al 2 O 3 and SiO 2.It mainly exists as minerals of …

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REMOVAL OF IRON-BEARING MINERALS FROM …

The refractory bauxite needs to present less than 2.5% of Fe 2 O 3 to be applied in the ceramics industry. The depletion of high Al 2 O 3 grade deposits has stimulated the improvement of bauxite concentration methods in order to remove iron-bearing minerals. The objective of this study was to evaluate the influence of collector dosage, pH and ...

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Removal of fluorine from red mud (bauxite residue) by …

1. Introduction. Red mud is a strong alkaline purplish-red powder-mud solid waste produced in the process of alumina extraction from bauxite. The production of 1 tonne of alumina generates about 1.5 tonnes of bauxite residue [1].According to statistics, the alumina industry produces more than 1.2 × 10 8 tonnes of red mud each year and …

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Beneficiation of Bauxite Ore Characterized by Low-Grade …

High-grade bauxite ore with an Al 2 O 3 /SiO 2 ratio exceeding 10 can undergo direct processing without any pre-treatment process. ... "Silicate" bacteria for silicate removal …

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Selectively leaching the iron-removed bauxite residues with phosphoric

The chemical compositions of the original BR and iron-removed BR are shown in Table 1.The main REEs in BR are La 2 O 3, Ce 2 O 3, Sc 2 O 3 and Y 2 O 3.As seen below the mass fraction of iron in original BR was significantly reduced from 21 wt% to 3.5 wt% after the iron removal treatment while the concentration of the Al 2 O 3, SiO 2, …

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Reverse flotation for removal of silicates from diasporic-bauxite

The diasporic-bauxite in China is characterized by a high content of Al 2 O 3 and SiO 2 and a low ratio of Al 2 O 3 to SiO 2 (m(Al 2 O 3)/m(SiO 2)=A/S, usually 5–6) compared with gibbsite–bauxite and boehmite–bauxite in other countries. The costs of producing aluminum oxide from such refractory bauxite by "sintering" or "combining ...

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Sulfur phase and sulfur removal in high sulfur-containing bauxite

Deciding the main sulfur form of high sulfur-containing bauxite could provide theoretical instruction for choosing methods for the removal of sulfur from bauxite, and an oxidizing-roasting process is an effective way to remove sulfide sulfur from high sulfur-containing bauxite, the content of S 2-in crude ore in the digestion liquor is above 1. ...

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Desilication and Recycling of Alkali-Silicate Solution for …

The residual bauxite concentrate was washed three times with boiling water and dried at 363 K for 12 h. The produced ASS was analyzed; the concentrations of SiO 2 and Na 2 O k in the ASS were 7–9 g/L and 90–110 g/L, respectively. Thereafter, the obtained ASS was subjected to silica removal by adding lime at a temperature of …

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Mechanism of ultrasonic-enhanced leaching for separating …

The existence of organic impurities in bauxite significantly hampers the regular production of alumina. This study proposes a low-temperature ultrasonic-enhanced alkali leaching to directly separate organic impurities from bauxite, and purify the leaching solution through H 2 O 2 oxidation and CaO precipitation. Under the optimal conditions …

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(PDF) Iron removal from bauxite ores

Bauxite reduced at 600 °C at H 2 gave high iron removal level, but quite small fraction was separated as non -magnetic material. In case t hat not all magnet ic iron i s removed from the bauxite ...

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Improving bio-desilication of a high silica bauxite by two …

Two highly effective Si-solubilizing bacterial strains H19 and G21 were obtained. • H19 and G21 could significantly (p < 0.05) remove Si from the high Si bauxite.The ratio of Al 2 O 3 /SiO 2 of the bauxite treated with H19 and G21 was more …

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Study on Calcination Characteristics of Diaspore-Kaolin Bauxite …

D-K-type bauxite from Guizhou can be used as an unburned ceramic, adsorbent, and geopolymer after low-temperature calcination. It aims to solve the problem where the color of the D–K-type bauxite changes after calcination at different temperatures. Digital image processing technology was used to extract the color characteristics of …

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Feasible conversion of solid waste bauxite tailings into …

A drawback of bauxite flotation is generation of additional solid wastes (known as bauxite tailings) equivalent to 30%, consisting of silica (SiO 2), and alumina oxide (Al 2 O 3), (approximately 70%), with small quantity of iron oxide (Fe 2 O 3), titania (TiO 2), potassium oxide (K 2 O), crystal water ((H 2 O) n) and other compositions (up to …

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Enhanced removal of iron minerals from high-iron bauxite …

The main mineral phases in high-iron bauxite were diaspore (AlOOH) and limonite (most of them are cryptocrystalline goethite (FeOOH)) together with a phase of quartz (SiO 2) and titanium dioxide (TiO 2). The mineral composition of raw ore was determined by identification of rock and minerals method according to the optical …

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Simultaneous removal of sulfur and iron by the seed …

Table 1 shows that the sample of the bauxite contains high silica, high sulfur with a low mass ratio of alumina to silica (A/S). This ore belongs to low-grade high‑sulfur bauxite. The proven reserves of this bauxite are >100 million tons and the prospective reserves are about 300 million tons in Nanchuan Chongqing, China (Yin et al., 2011). ...

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Sodium removal from bauxite desilication product …

Sodalite (SOD) is one of the predominant alkaline minerals in BR, whose chemical formula can be described as Na 6 (AlSiO 4) 6 (NaOH) 2 (H 2 O) 2 in the basic environment (Wang et al., 2019).Each SOD unit cell consists of 6-membered rings (6R) and 4-membered rings (4R) formed from alternating SiO 4 and AlO 4 tetrahedrals. The rings …

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Removal of aluminosilicates from diasporic-bauxite by …

The major element composition of the bauxite is dominated by elevated concentrations of SiO 2, TiO 2, Al 2 O 3, and Fe 2 O 3, and analyses of element mobility within the bauxite indicate that all elements except for Nb and Ni, and to a lesser extent Cr, are depleted relative to the immobile element Ti.

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Research on Impurity Removal of Low Grade Bauxite

Shortages of bauxite resources are very severe with the rapid development of alumina and refractory industry in recent years [3,4,5]. To realize a sustainable development of the refractory industry, it has been suggested that beneficiation and purification should be made on the bauxite with low ratio of Al 2 O 3 /SiO 2 and high …

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Separation of silica from bauxite via froth flotation

In China, low grade diasporic bauxite with an Al 2 O 3 /SiO 2 mass ratio below 8 can be processed by sintering, or through a combination of sintering and the …

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Extraction of Iron and Ferrosilicon Alloys from Low-Grade …

The Characteristics of the Ores. The XRD analysis data for the bauxite ores in Fig. 2 shows that Bauxit I contains Al 2 O 3 -containing phases of kaolinite (Al 2 …

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Dissolution kinetics and removal mechanism of kaolinite …

Trans. Nonferrous Met. Soc. China 29(2019) 2627âˆ'2637 Dissolution kinetics and removal mechanism of kaolinite in diasporic bauxite in alkali solution at atmospheric pressure Yan WU, Xiao-lin PAN, Yue-jiao HAN, Hai-yan YU School of Metallurgy, Northeastern University, Shenyang 110819, China Received 29 March 2019; …

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Sulfur phase and sulfur removal in high sulfur-containing bauxite

The removal of sulfur from bauxite has attracted considerable attention in recent years with the rapid development of the alumina industry [3âˆ'7]. There are two basic processes for extracting alumina from bauxite, namely, the sintering process and the Bayer process. The disadvantage of the sintering process is its low efficiency (low to 33 ...

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Characterization and flotation of low-grade boehmitic bauxite …

Bauxite is the main raw material in primary aluminum production and its reactive silica content and mass ratio of Al 2 O 3 to SiO 2 (A/S) has a critical role in the economic viability of Bayer process. As a major source of the reactive silica, clay impurities should be removed from the ore as much as possible by a beneficiation method such as …

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Review Summary of sulfur hazards in high‑sulfur bauxite and

Li et al. studied the mineral phase transformation of roasted bauxite, and at a roasting temperature of 1050 °C for 30 min, the dissolution rates of Al 2 O 3 and SiO 2 were 94 % and 88 %, respectively, and the content of Fe 2 O 3 in the leaching slag was 55.23 %, which can be used as an iron ore concentrate directly for ironmaking to realize ...

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REMOVAL OF IRON-BEARING MINERALS FROM GIBBSITIC BAUXITE …

SiO 2 content presented a reduction from 4.95% to 2.71% . ... iron-bearing minerals removal from the bauxite since the . SiO 2 and Fe 2 O 3 contents (9.75% and 7.72%, respectively)