Red mud project site dedicated on the valorisation and best. Ree content in red mud has been shown to double as a result of the bayer process11 and this is consistent in both jamaican. Mineral compositionof the red mud depends on the mineral composition of the source material bauxite. Depending on the origin, quality and composition of the bauxite, the amount of red mud left over from the alumina refining can vary widely. Red mud is toxic for the environment due to high alkalinity, salinity and trace metals. A major challenge going forward is to reconcile mans activities on earth with the key pillars of environmental stewardship, sustainability and safeguarding life forms. It is reported that, there are up to 3 million tons of red mud. Johannes vind goes in search of the sources of red mud.
Its disposal remains a worldwide issue in terms of environmental concerns. Red mud is a byproduct of bauxite processing via the bayer process. Red mud contains high quantities of alkaligenerating minerals and metal ions, which can cause significant environmental damage. Bauxite is not a mineral, but rather a group of aluminum oxide s. It is a mixture of hydrous aluminum oxides, aluminum hydroxides, clay minerals, and insoluble materials such as quartz, hematite, magnetite, siderite, and goethite. Bauxite industry in guinea and value opportunities of the. Chemistry of trace and heavy metals in bauxite residues. Longterm neutralisation potential of red mud bauxite with brine amendment for the neutralisation of. Red mud is the industrial waste generated during the production of alumina.
Dealing with red mud by product of the bayer process. Dealing with red mud by product of the bayer process for. The composition and properties of rm depend on the bauxite ore sources and production processes. The disposal of red mud leads to a serious environmental threat because of its tiny particle size and high alkaline value. Red mud is a concentration of many elements, aluminium mainly. Study of red mud as an alternative building material for. Summer school zerowaste valorisation of bauxite residue red mud summer school 2931 august 2016, leuven, belgium. In the institute of metallurgy of the ural branch of the russian academy of sciences, red mud is utilised by introducing it into the charge. Pdf red mud or bauxite residue is a solid waste generated from.
It is present in the form of slurry having 1030% solid materials milacic et al. Fabrication and characterisation of ghanaian bauxite red mud. This experimental research was to evaluate the feasibility of blends red mud derived from bauxite calcination method with other industrial wastes for use as a cementitious material. Red mud or bauxite residue is a solid waste generated from the bayer process. Wong jwc, ho ge 1993 use of waste gypsum in the revegetation on red mud. According to the grade of the bauxite ore, 23 tonnes of ore yield one tonne of alumina and about one tonne of red mud dry weight. Characterization and applications of red mud from bauxite. When designing an alumina plant, factors other than the type of bauxite ore to be used as feed material and the form of alumina to be produced have to be taken into consideration. Bauxite does not make aesthetic or interesting specimens as far as collectors are concerned. Composition of bauxite and the generated red mud compound as shown. Using red mud bauxite for the neutralization of acid mine tailings.
Bauxite potential of guinea whatever concepts and definitions used, it appears from all studies that guinea is the country the most endowed with bauxite in the world. Bauxite residue, or red mud, is a solid waste produced from the alumina refining of bauxite ore. Dr mark harris has a tried and proven formula that could transform the islands potentially harmful bauxitealumina red mud. Typical chemical composition and metal content of bayer process red mud are. With the rapid development of iron and steel industry and aluminum industry, highquality iron ore and bauxite resources become increasingly tense. The longterm storage of bauxite residue red mud is harmful to the environment and the tailing ponds also cover large areas. Ncu scientist points to recognised solution for alumina dumps. The term is generally used to describe the economically important mixture of these minerals, which form a mass of the individually classified members of gibbsite, boehmite, and diaspore. Successes and challenges in the bauxite residue valorization.
Chemistry of the acid neutralization capacity of bauxite. Evaluation of blends bauxitecalcinationmethod red mud. The opening chapters present observational and analytical evidence concerning karst bauxite, with particular emphasis on. In china, large quantities of red mud derived from bauxite calcination method are being discharged annually, and its utilization has been an urgent topic. At the moment there is no largescale utilization of bauxite residue.
Nov 26, 2019 the bayer process is the cornerstone of global aluminum production. Methods for alkaline recovery of aluminum from bauxite residue. Mar 19, 20 bauxite residue is often referred as red mud due to the colour of the bauxite ore and iron oxides. Garrett emeritus scientist, geological survey ofcanada, ottawa. Composition of bauxite and the generated red mud compound as shown in table. This book is divided into eight chapters that highlight the quantitative processing and assessment of the information available for bauxites. Composition and properties of red mud in the world have been presented by many researchers in their publications. Known formally as bauxite residue, red mud is the noxious byproduct of the bayer process for extracting aluminum from bauxite ore. Aug 11, 2016 the longterm storage of bauxite residue red mud is harmful to the environment and the tailing ponds also cover large areas. Bauxite deposits on carbonate rocks presents a comparison of bauxite regions using mathematical statistics methods. The aluminum mineral bauxite information and pictures. The actual composition of red mud depends on the type of bauxite, the mining location and the process parameters of the bayer process40.
It is the insoluble product after bauxite digestion with sodium hydroxide at elevated temperature and pressure. Stateoftheart formation of red mud during industrial processing of bauxite in the sverdlovsk region russian federation is presented. Bauxite tailings, also known as bauxite residue, red mud, red sludge, or alumina refinery. The bayer process also creates an insoluble mixture of compounds known as red mud rm, which, at present, is regarded as waste. Making the most of red mud february 24, 2014 issue vol. As to the recovery of valuable metals from ironrich bauxite and red mud, there are a lot. Researchers from csiros mineral resources flagship have developed a process that lowers the cost of refining bauxite aluminium ore to alumina aluminium oxide by treating the waste product generatedred mudto recover a costly ingredient, caustic soda. Red mud is produced during the bayer process for alumina production. Pdf the composition, recycling and utilisation of bayer red mud. The production of 1 t of alumina generally results in the creation of 11. The composition, recycling and utilisation of bayer red mud. Bauxite does not make aesthetic or interesting specimens as far as collectors are concerned, but it holds importance as being the primary ore of.
This involves refining the mineral ore bauxite to generate aluminum oxide alumina, which gives aluminum when smelting 1. However, a lot of ironrich bauxite and bayer red mud resources have not been timely and effectively recycled, resulting in serious problems of environmental pollution and wastage of resources. A novel process for making radiopaque materials using. Fabrication and characterisation of ghanaian bauxite red. Described herein is a process that converts the red mud into mineral products that can be used for commercial applications. Recovery of rare earths and other valuable metals from.
Bauxite tailings, also known as bauxite residue, red mud, red sludge, or alumina refinery residues arr, is a highly alkaline waste product composed mainly of iron oxide that is generated in the industrial production of alumina aluminium oxide, the principal raw material used in the manufacture of aluminium metal and also widely used in the manufacture of ceramics, abrasives and refractories. Xrd data measured in a quick timespan with the lynxeye detector, the use of coradiation and the topas software enables a quick and accurate quantitative investigation of multiphased samples containing iron. This involves refining the mineral ore bauxite to generate aluminum oxide alumina, which gives aluminum when smelting 1 the bayer process also creates an insoluble mixture of compounds known as red mud rm, which, at present, is regarded as waste. Red mud is a toxic byproduct of the industrial process that refines bauxite, raw aluminum ore, into aluminum oxide, or alumina. Jul 08, 2003 red mud is a byproduct of bauxite processing via the bayer process. Alumina is put through a separate process, electrolysis, to make.
The comprehensive utilisation of red mud utilisation in. Bauxite residue generation balance between aluminous content of the bauxite, type of aluminium containing compound, local energy cost, transport cost, silica content reactive more important than crystalline when plants located very distant from the bauxite source, they tend to use high alumina bauxite and high. Red mud is mostly collected from the bayer process which uses sodium hydroxide to dissolve the aluminium silicate. Many valuable components such as rareearth elements, al, and fe, in rm are difficult to be utilized owing to their particle size and alkalinity. The comprehensive utilisation of red mud utilisation in blast. As the temperature and pressure increases, the solubility of red mud decreases with sodium hydroxide nie et al. Parekh and goldberger 1976 5red mud is a residual waste generated during the extraction of alumina from bauxite by buyers process. Abstract bauxite residue red mudrm, a byproduct of the bayer process for refining bauxite to alumina, is highly alkaline ph. Bauxite potential of guinea whatever concepts and definitions used, it appears from all studies that guinea. Red mud is a product of the bayer process during the production of alumina hairi et al. Bauxite residue is often referred as red mud due to the colour of the bauxite ore and iron oxides. Red mud rm is a byproduct of extracting of alumina from bauxite. Red mud in an liquid state causes harmful effects to human skin.
Review the composition, recycling and utilisation of bayer red mud. Its composition depends upon its parent material from which it is produced liu and wu, 2012. However, some bauxite residues contain considerable concentrations of rareearth elements rees and the recovery of these rees together without other metals and utilization of the generated. Annually, it is estimated that approximately 117 million tons of red mud are generated in the world, with no prospect of use, what represents an imminent risk of.
Red mud is a waste material derived as residual from the bayer process by the caustic digestion of crushed bauxite at elevated temperature. A novel process for making radiopaque materials using bauxite. Bauxite tailings, also known as bauxite residue, red mud, red sludge, or alumina refinery residues arr, is a highly alkaline waste product composed mainly of iron oxide that is generated in the industrial production of alumina aluminium oxide, the principal raw material used in the manufacture of aluminium metal and also widely used in the. The xrd pattern for the bauxite, red mud and clay samples are shown figure5 and supported with xrf analyses in table2. Bauxite residues also known as red mud, bayer process tailings or bauxite process tailings are generated from alumina production where bauxite is digested in hot naoh solution via the bayer process. The bayer process is the cornerstone of global aluminum production. Red mud project site dedicated on the valorisation and. Bauxite is a multiphase ore that may contain, according to some referen. Demonstrated the red mud compositions and its disposal and environmental.
Jun 21, 2011 bauxite is leached under high temperature and pressure with sodium hydroxide solution and insoluble material also termed as red mud is separated to form a solution that is seeded to precipitate aluminum hydroxide that finally is calcined to alumina. Red mud is a solid waste residue of the digestion of bauxite ores with caustic soda for alumina production. Methods for alkaline recovery of aluminum from bauxite. Red mud is a waste originated in the processing of bauxite into aluminium, which properties of high alkalinity make it cumulatively stored, occupying increasing deforested areas. To force reaction 1, elevated or even high temperatures are necessary depending on the mineralogy of the processed bauxite.
It is a mixture of compounds originally present in the parent mineral, bauxite, and of compounds formed or introduced during the bayer cycle. Lancashire, bauxite and aluminium production, education in chemistry, may 1982, pps 6264. According to the grade of raw material bauxite and the production process of alumina, red mud can be divided into bayer red mud and sintering red mud 1,2. Topas rietveld analysis is being used as a routine tool in quantitative phase analysis of powder samples. The table below shows the composition ranges for common chemical constituents, but the. Phytoremediation of bauxitederived red mud by giant reed.
511 146 36 1499 1503 1528 1057 1380 1394 59 1091 1251 1012 375 651 1300 1079 452 1264 1117 779 1111 773 796 934 437 100 669 811 1294 308 1495 998 111 193 1357 670 591 1064 1414 1495