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WO2012145797A1 Recovery of soda from bauxite residue

A process for recovery of soda from Bayer process bauxite residue comprises the steps: (a) leaching bauxite residue with sulphuric acid to dissolve soda in DSP in bauxite residue therein; (b) neutralizing the slurry of step (a) with caustic materials to precipitate partially dissolved silica, alumina and calcium, and separating the insoluble portion with precipitated materials by filtration to

AU2012248126A1 Recovery of soda from bauxite residue

A process for recovery of soda from Bayer process bauxite residue comprises the steps: (a) leaching bauxite residue with sulphuric acid to dissolve soda in DSP in bauxite residue therein; (b) neutralizing the slurry of step (a) with caustic materials to precipitate partially dissolved silica, alumina and calcium, and separating the insoluble portion with precipitated materials by filtration to

RECOVERY OF SODA FROM BAUXITE RESIDUE BY ACID

The leached residues after soda recovery showed a low and stable pH and, of course, lower soda. This is expected to be of great benefi t to long term residue management. 1. Introduction A worldwide trend of declining bauxite grades underlines the importance of research into practical ways of

Bauxite Residue an overview ScienceDirect Topics

In this process, the milled bauxite is digested in caustic soda, and then during the solid liquid separation stage the leach residue red mud is collected (Figure 14.1). Before it is sent for disposal, it is washed several times to recover the soda.

Bauxite residue issues: I. Current management, disposal

Jun 01, 2011 The bauxite residue is then separated from the main liquor stream and washed to recover soda and alumina. The resulting residue contains pore water that is considerably more dilute (by a factor of at least 10) than the main Bayer plant liquor, but is nevertheless highly alkaline.

Smelting of bauxite residue to form a soluble sodium

Jul 18, 2013 The rate and extent of dissolution of alumina and soda increased in a water leach as the CaO/SiO 2 ratio in the slag was increased from 0·1 to 2 by the addition of calcium carbonate to the dried bauxite residue. A water leach at 60°C, extracted 55% of the Al and 90% of the Na at 20 wt-% solids and 50 and 75% respectively, at 50 wt-% solids.

Mining and Refining Bauxite Residue Management

Bauxite residue is a by-product of the Bayer Process. It is primarily composed of the insoluble fraction of the bauxite ore that remains after extraction of the aluminium-containing components. Iron oxides (10 30%), titanium dioxide (2 15%), silicon oxide (5 20%) and undissolved alumina (0 20%) make up the residue, together with

Minerals Free Full-Text A Combined Soda Sintering and

Figure 4 shows the mineralogical alteration of the bauxite residue after soda sintering process and mild alkaline leaching process. During the sintering step, aluminum bearing species such as boehmite, diaspore, gibbsite, and complex phases such as cancrinite are transformed into sodium aluminate (NaAlO 2

Bauxite Residue Management World Aluminium

b. Production of bauxite residue The amount of bauxite residue produced by an alumina plant or refinery is primarily dependent on the sources of the bauxite and secondarily on the extraction conditions used by the plant. In the extreme, this can vary from 0.3 to as high as 2.5 tonnes of residue per tonne of alumina produced, though typically

ARTICLE: Addressing the Challenge of Bauxite Residue

Mar 11, 2019 The largest waste by-product generated in the Bayer bauxite refining process is bauxite residue, commonly called red mud. An enormous quantity of caustic red mud is generated worldwide every year, posing a very serious and alarming environmental and safety problem. The storage of red mud is a challenge for alumina refineries (Figure 1), as

Management and use of bauxite residue

of bauxite residue *Consultant, International Aluminium Institute This paper serves as a brief overview of the history and trends in the management of the caustic soda value and avoiding contaminating the environment. Various drainage and seepage collection systems

Bauxite residue uses: successes, failures and

with bauxite residue •Recovery of caustic soda for reuse in the process •Lowest cost compatible with minimum effect on the environment •A desire for use but needed to be a cost effective solution •Occasional attempts to use –for example in times of war –used in iron and steel production

Bauxite Residue Management World Aluminium

b. Production of bauxite residue The amount of bauxite residue produced by an alumina plant or refinery is primarily dependent on the sources of the bauxite and secondarily on the extraction conditions used by the plant. In the extreme, this can vary from 0.3 to as high as 2.5 tonnes of residue per tonne of alumina produced, though typically

Geotechnical characterization of bauxite residue (red mud)

Bauxite residue is the iron-oxide rich mine waste from the processing of bauxite ore for the extraction of alumina through the Bayer process. The Bayer process uses caustic soda, high pressure, and high temperature to leach alumina from ferruginous residue slurry (bauxite residue or red mud).

Production Red Mud Project

Jul 13, 2005 Bauxite Residue accident from Norwegian Hydro in Brazil; The major impurity, residual soda, is present at levels of 0.2 to 0.6 percent. In addition to being the primary raw material for producing metallic aluminum, alumina itself is an important chemical. It is used widely in the chemical, refractories, ceramic, and petroleum industries.

Minerals Free Full-Text A Combined Soda Sintering and

In this study an integrated process is presented as a suitable method to transform Fe3+ oxides present in bauxite residue into magnetic oxides and metallic iron through a microwave roasting reduction, avoiding the formation of hercynite (FeAl2O4). In the first step, all the alumina phases were transformed into sodium aluminates by adding sodium carbonate as a flux to BR and then leached out

ENVIRONMENTAL ASPECTS OF BAUXITE, ALUMINA AND

In alumina production, the disposal of bauxite residue saturated with caustic soda ("red mud") is the main problem, although emissions to the atmosphere of gases and particles from boilers, calcination furnaces and bauxite dryers may also be important. Worldwide, the most common method of disposal of

Industrial wastes applications for alkalinity regulation

Feb 02, 2019 高达10%返现 Bauxite residue is a highly alkaline material generated from the production of alumina in which bauxite is dissolved in caustic soda. Approximately 4.4 billion tons of bauxite residues are either stockpiled or landfilled, creating environmental risks either from the generation of dust or migration of filtrates. High alkalinity is the critical factor restricting complete utilization of bauxite

Electrolytic Iron Production from Alkaline Bauxite Residue

3% of the annual bauxite residue production (8). The main constituent of bauxite residue is iron oxide and it can make up to 45% of the mass of the bauxite residue. In fact, the red colour of bauxite residue is caused by iron(III) oxides (mostly haematite, Fe 2O 3) (9). In general, due to its high alkaline (Na 2O ≈ 10%) and its titanium (TiO

Red mud Wikipedia

Red mud, formally termed bauxite residue, is an industrial waste generated during the processing of bauxite into alumina using the Bayer process.It is composed of various oxide compounds, including the iron oxides which give its red colour. Over 95% of the alumina produced globally is through the Bayer process; for every tonne of alumina produced, approximately 1 to 1.5 tonnes of red mud are

Alumina Refining The Australian Aluminium Council

After several washing stages to recover caustic soda, the residue is pumped to storage dams. The solution of alumina in caustic soda is further clarified by filtration. The bauxite residue is safely stored, in ways which meet industry best practice and required safety standards.

Bauxite residue issues: I. Current management, disposal

The global inventory of bauxite residue reached an estimated 2.7 billion tonnes in 2007 increasing at 120 million tonnes per annum. This growth highlights the urgency to develop and implement improved means of storage and remediation, and to pursue large-volume utilization options of residue as an industrial by-product.

(PDF) BAUXITE RESIDUE MANAGEMENT Ken Evans

BAUXITE RESIDUE MANAGEMENT. Ken Evans. IntroductionBauxite residue has been continuously produced since the development of the alumina/aluminium industry in the late nineteenth century -and the global inventory is estimated to be around 3,000 million tonnes at the end of 2010 [ 1 Klauber, C., Grafe, M., and Power, G, 2009] -and growing at

The use of Bauxite Residue for Phosphorus P

3. Bauxite residue as an adsorbent for phosphorus (P) 4. My study and results. Phosphorus • Phosphorus is a non-metal and a key component in the composition of animals and plants; essential for successful crop yields. • Phosphorus is added to land through the use of fertilisers. 1. 2.

RECOVERY OF SODA FROM BAUXITE RESIDUE BY ACID

Caustic soda consumption is a significant production cost when high silica bauxite is processed in an alumina refinery. The authors have developed a new process to recover soda from desilication product (DSP) in bauxite residue (BR), which comprises the following steps: (1) leaching DSP by sulphuric acid to extract soda as sodium sulphate, (2) purification of the leached liquor and (3

"Effect of application of bauxite residue (red mud) to

Bauxite residue (red mud) is the byproduct from treatment of crushed bauxite with caustic soda to produce alumina. When dried the residue is alkaline and has a high capacity to retain phosphorus (P). The residue is added to pastures on acidic sandy soils to increase the capacity of the soils to retain P so as to reduce leaching of P into waterways and so reduce eutrophication of the waterways.

In situ remediation of bauxite residue by sulfuric acid

In situ remediation of a bauxite residue by integrating a storage area with CSIRO's soda recovery process was evaluated. The process consisted of the following steps: bauxite residue is neutralized with sulfuric acid; the slurry is separated into a neutralized residue and a leachate. The residue is sent to a storage area and washed with rainfall.

Geotechnical characterization of bauxite residue (red mud)

Bauxite residue is the iron-oxide rich mine waste from the processing of bauxite ore for the extraction of alumina through the Bayer process. The Bayer process uses caustic soda, high pressure, and high temperature to leach alumina from ferruginous residue slurry (bauxite residue or red mud).

Production Red Mud Project

Jul 13, 2005 Bauxite Residue accident from Norwegian Hydro in Brazil; The major impurity, residual soda, is present at levels of 0.2 to 0.6 percent. In addition to being the primary raw material for producing metallic aluminum, alumina itself is an important chemical. It is used widely in the chemical, refractories, ceramic, and petroleum industries.

Successes and challenges in the Bauxite Residue Valorization

dealing with bauxite residue •Recovery of caustic soda for reuse in the process •Lowest cost compatible with minimum effect on the environment •A limited desire for (re)use but needed to be a cost effective solution •Occasional attempts to (re)use –for example in times of war –iron and steel production •Disposal cost –US$ 4 to 10/t

Red mud addressing the problem Aluminium Insider

Nov 15, 2016 Sodium in the caustic soda then combines with reactive silica to produce the residue red mud waste, which falls out of the solution taking the sodium with it. The loss of sodium represents a significant cost. This means that the higher the level of reactive silica in the ore, the more expensive it is to refine. Much of the bauxite residue

Electrolytic Iron Production from Alkaline Bauxite Residue

3% of the annual bauxite residue production (8). The main constituent of bauxite residue is iron oxide and it can make up to 45% of the mass of the bauxite residue. In fact, the red colour of bauxite residue is caused by iron(III) oxides (mostly haematite, Fe 2O 3) (9). In general, due to its high alkaline (Na 2O ≈ 10%) and its titanium (TiO

(PDF) BAUXITE RESIDUE MANAGEMENT Ken Evans

BAUXITE RESIDUE MANAGEMENT. Ken Evans. IntroductionBauxite residue has been continuously produced since the development of the alumina/aluminium industry in the late nineteenth century -and the global inventory is estimated to be around 3,000 million tonnes at the end of 2010 [ 1 Klauber, C., Grafe, M., and Power, G, 2009] -and growing at

EXTRACTION Bauxite Residue Valorisation and Best

Jun 28, 2018 Red-Mud (Bauxite residue) is a byproduct generated during the Bayers processing of bauxite. Iron is a major constituent in most of the world’s reserves of bauxite residue (3 billion tons). 22-26] and aluminum silicates [27] by employing a soda ash/sodium carbonate and carbon based roasting. Magnetic separation was performed to separate

Neutralization of red mud using inorganic acids — Kyung

Red mud' or 'bauxite residue' is a waste generated from alumina refinery in an enormous quantity posing a very serious and alarming environmental problem due to its high causticity. Red mud is highly alkaline in nature with a pH of 10.5-12.5 due to caustic soda solution used in extraction of alumina from bauxite ore using Bayer process.

Bauxite residue issues: I. Current management, disposal

The global inventory of bauxite residue reached an estimated 2.7 billion tonnes in 2007 increasing at 120 million tonnes per annum. This growth highlights the urgency to develop and implement improved means of storage and remediation, and to pursue large-volume utilization options of residue as an industrial by-product.

(PDF) Characterization of Bauxite Residue in Bukit Goh

Characterization of Bauxite Residue in Bukit Goh, Pahang, Malaysia. Journal for Studies in Management and Planning,2018. E. Foday Jr. Download PDF. Download Full PDF Package. This paper. A short summary of this paper. 37 Full PDFs related to this paper. READ PAPER.

Industrial wastes applications for alkalinity regulation

Bauxite residue is a highly alkaline material generated from the production of alumina in which bauxite is dissolved in caustic soda. Approximately 4.4 billion tons of bauxite residues are either stockpiled or landfilled, creating environmental risks either from the generation of dust or migration of filtrates. High alkalinity is the critical factor restricting complete utilization of bauxite