The present invention provides a process for removing silica from bauxite that may allow for substantially complete removal (certainly in excess of 80% removal) of reactive silica from the...
WhatsApp: +86 18221755073
The main objective of bauxite beneficiation is to lower the concentration of reactive silica, and also to increase the alumina content. In addition, bauxite beneficiation can also be used for iron extraction or iron …
WhatsApp: +86 18221755073
Bauxite is widely used to produce alumina. There are many bauxite resources with high iron content. These resources could not be processed and utilized efficiently due to the high concentration of iron (Fe). The alkaline leaching process has been proposed to remove iron from these bauxite resources. Therefore, in this study, the alkaline leaching process was employed, …
WhatsApp: +86 18221755073
Efficient utilization of high-silica bauxite and minimization of bauxite residue are of great significance for the sustainable development of the alumina industry. In this paper, a novel process is proposed to extract Al2O3 and SiO2 from high-silica bauxite without residue discharge, that is, sintering bauxite with
WhatsApp: +86 18221755073
A schematic of the silica removal from bauxite and the desilication process is presented in Fig. 1. All experiments were carried out at 95 °C. The desilication test was carried out in a constant temperature (≈95 °C) oil bath with electromagnetic stirring (≈300 rpm), and RM and/or CaO were added. After filtration and cooling, the ...
WhatsApp: +86 18221755073
bauxite silica removal Prior art date Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.) Withdrawn Application number EP97911968A Other languages German (de) French (fr) Other versions ...
WhatsApp: +86 18221755073
Bauxite is the most important raw material for production of aluminium metal and in the manufacture of abrasives, ceramics and refractories. Depending on the end use of the mined bauxite ores, appropriate prebeneficiation need to be adapted for removal of impurities such as calcium, iron oxides and silica.
WhatsApp: +86 18221755073
A process for removing silica from bauxite is disclosed. The method includes the step of mixing bauxite with a caustic liquor to form a mixture and to dissolve and stabilise at least a substantial part of the reactive silica from the bauxite. The caustic liquor is selected to have a high caustic concentration and a high alumina content. The method further includes the step of separating …
WhatsApp: +86 18221755073
The Bayer process is a chemical process for refining aluminium hydroxide, Al(OH) 3 from bauxite; this aluminium hydroxide is subsequently calcined to produce alumina, Al 2 O 3.The basis of the Bayer process is an understanding of the characteristics of the sodium-hydroxide—sodium-aluminate solution relationship, namely its ability to keep sodium-aluminate in a dissolved state …
WhatsApp: +86 18221755073
A process for removing silica from bauxite is disclosed. The method includes the step of mixing bauxite with a caustic liquor to form a mixture and to dissolve and stabilise at least a substantial part of the reactive silica from the bauxite. The caustic liquor is selected to have a high caustic concentration and a high alumina content.
WhatsApp: +86 18221755073
Bauxite residue is a solid waste left over after extracting alumina from bauxite. When high-silica bauxite is used as a feedstock for alumina production, more bauxite residue is discharged compared to processing high …
WhatsApp: +86 18221755073
During the extraction of alumina from siliceous (non-bauxite) minerals by alkaline leaching some of the silica enters the solution as silicate ions. In order to obtain high-grade aluminium hydroxide, it is necessary to remove this from the aluminate solutions.
WhatsApp: +86 18221755073
Furthermore, the grade of bauxite could be enhanced by removing silica with Bacillus polymyxa (Anand et al., 1996). Bacteria promoted Si release from Si-bearing rocks and minerals through the production of microbial metabolites such as organic acids and expolyssaccharides ( Gehrke et al., 1998, Pradhan et al., 2006, Sheng et al., 2008 ).
WhatsApp: +86 18221755073
A process for removing silicon dioxide from bauxite is disclosed. The method includes the step of mixing bauxite with a caustic soda liquor to form a mixture and to dissolve and stabilise...
WhatsApp: +86 18221755073
The bauxite from Pará-Brazil is a mixture of minerals where gibbsite (Al(OH)3), kaolinite (Al4[Si4O 10](OH)8), quartz, hematite, goethite, rutile and octahedrite are the most important minerals.
WhatsApp: +86 18221755073
In view of beneficiation action of bauxite, removal of maximum silica content from the feed ore is removal of silica content that are active in nature before entering into digestion is the concept.
WhatsApp: +86 18221755073
More than 99% of the iron could be extracted under optimized conditions [109,110]. Valeev et al. [111] found that pre-calcination of Severoonezhsk bauxite at 700 • C for 0.5 h resulted in a ...
WhatsApp: +86 18221755073
Aluminum production from bauxite is achieved with the Bayer process, which is a hydrometallurgical method. However, in the Bayer process, in time, it is possible to encounter problems such as the formation of excessive amounts of red mud in aluminum production, its environmental risks, its requirement of large storage sites, the excessive production of …
WhatsApp: +86 18221755073
General industrial flowsheet for removal of silica from Bauxite. Full size image. Depending on the particle size distributions and washing characteristics of individual bauxites, some of the coarse higher grade dry or wet fractions can be removed before the attrition scrubber. In order to save water and avoid washing all of the bauxite, it can ...
WhatsApp: +86 18221755073
Batch pre-desilication test results of a high reactive silica boehmitic bauxite from Nyírád (Hungary) ar e shown on Figures 4.4-9 [8]. The bauxite contained 48.8 % Al 2 O 3, of which 37 % was ...
WhatsApp: +86 18221755073
In this study, low-grade bauxite ore from Seydişehir (Konya, Turkey) containing 57.33% Al2O3 and 9.01% SiO2, (A/S = 6.36) was investigated to determine the modal mineralogy and mineral liberation ...
WhatsApp: +86 18221755073
A process for removing silica from bauxite is disclosed. The method includes the step of mixing bauxite with a caustic liquor to form a mixture and to dissolve and stabilise at least a substantial part of the reactive silica from the bauxite. The caustic liquor is selected to have a high caustic concentration and a high alumina content.
WhatsApp: +86 18221755073
WO 98/22390 PCT/AU97/00786 1 REMOVAL OF SILICA FROM BAUXITE The present invention relates to a process for desilicating bauxite. Bauxite is the major source of aluminium containing ore used in the production of alumina. Bauxite contains hydrated forms of aluminium oxide (alumina) that occur in several different structural forms, depending upon ...
WhatsApp: +86 18221755073
(57) Abstract: discloses a method for removing silica from bauxite. The method, bauxite were formed by mixing the mixture with an alkaline solution, it includes various steps to stabilize by dissolving at least substantially a portion of the reactive silica from bauxite. Alkaline solution is chosen to have a high alkali concentration and a high alumina content. The method of the …
WhatsApp: +86 18221755073
Research has been carried out in order to develop a process to upgrade European bauxite deposits by removing the silica fraction associated with the aluminosilicates by …
WhatsApp: +86 18221755073
For achieving this purpose, iron removal tests were performed on bauxite samples with an alumina to silica modulus of 0.73. After determining the appropriate iron removal method among the magnetic ...
WhatsApp: +86 18221755073
Reduction of Reactive Silica from Bauxite Fernanda A. N. G. Silva 1, Barbato, C. N. 3, Almeida, D. S. G. 1, 2 João A. Sampaio 2, Marta E. ... removal of the fine fraction (-37 µm) by screening ...
WhatsApp: +86 18221755073
There is currently no widely accepted alternative method for removing silica from Bayer liquor which does not lead to soda loss. A side implication of this is that bauxites containing high …
WhatsApp: +86 18221755073
A process for removing silicon dioxide from bauxite is disclosed. The method includes the step of mixing bauxite with a caustic soda liquor to form a mixture and to dissolve and stabilise at least a substantial part of the reactive silicon dioxide from the bauxite. The caustic liquor is selected to have a high caustic concentration and a high alumina content.
WhatsApp: +86 18221755073
Improving kaolinite-bearing bauxite by preroasting is a potential method for removing silica from ore and incorporating it into the Bayer process. Caustic soda consumption is significantly reduced if precalcined bauxite is used in the Bayer process [ 6 ].
WhatsApp: +86 18221755073
This paper reports an innovative development: concentrating gibbsite via reverse froth flotation in order to obtain a metallurgical-grade bauxite concentrate. Tailings from an …
WhatsApp: +86 18221755073
The present invention provides a process for removing silica from bauxite that may allow for substantially complete removal (certainly in excess of 80% removal) of reactive silica from the bauxite. Moreover, the dissolved silica stays in solution for sufficient time to enable solid/liquid separation to take place without substantial ...
WhatsApp: +86 18221755073
Efforts to remove reactive silica from bauxite ore prior to shipment have largely focused on gravitational methods such as washing, screening and the use of hydrocyclones. The purpose …
WhatsApp: +86 18221755073