Characterization of Settled Particles of the Red Mud Waste Exposed to Different Aqueous Environmental Conditions (original) (raw)
Related papers
Current Status of an Industrial Waste: Red Mud an Overview
Red mud is a solid residue Produced during the alumina production by the bayer process from bauxite. The red mud generated by this process is highly alkaline with pH usually ranging from 10 to 13. Due to its hazardous corrosive nature its posing a very serious and alarming environmental problem. Globally there are approximately 90 million tonnes of red mud being produced every year. More than 4 million tons of red mud is generated annually in India only. The amount of the red mud generated per ton of the alumina processed, varies greatly with the type of the bauxite ore used. Due to its hazardous nature it is a great challange to researcher to develop new methods for the application of red mud. Various research work going on for the storage, disposal and utilization of the red mud in all over the world. This paper reviews the current status and future trend of the red mud characterization, disposal, various neutralization methods and utilization in world as well as in Indian context.
Revista de Chimie, 2019
The red mud is the main insoluble waste product from the manufacture of alumina by the Bayer hydrometallurgical process. Due to the accumulation in large quantities (0.8-1.2 metric tons waste / 1 metric ton of alumina) with a relatively high content of residual alkali and small granulation, it has been subject to many research activities, especially related to the techniques of neutralizing and enhancing its reuse under the form of various subproducts. This paper presents the results of the work undertaken by the collective of authors to evaluate the physico-chemical and morphological structure of red mud resulting from alumina production. The physico-chemical and morphological structure were analyzed using complex analytical methods (ICP-AES/OES, DCP, AAS, EDS-EDAX, SEM, DTAC, XRF, XRD, optical microscopy). The aim was to identify potentially active compounds for various environmental applications. To estimate the average chemical composition, by element, we used dispersion analysi...
Treatment of alumina refinery waste (red mud) through neutralization techniques: A review
Waste Management & Research: The Journal for a Sustainable Circular Economy, 2017
In the Bayer process of extraction of alumina from bauxite, the insoluble product generated after bauxite digestion with sodium hydroxide at elevated temperature and pressure is known as ‘red mud’ or ‘bauxite residue’. This alumina refinery waste is highly alkaline in nature with a pH of 10.5–12.5 and is conventionally disposed of in mostly clay-lined land-based impoundments. The alkaline constituents in the red mud impose severe and alarming environmental problems, such as soil and air pollution. Keeping in view sustainable re-vegetation and residue management, neutralization/treatment of red mud using different techniques is the only alternative to make the bauxite residue environmentally benign. Hence, neutralization techniques, such as using mineral acids, acidic waste (pickling liquor waste), coal dust, superphosphate and gypsum as amenders, CO2, sintering with silicate material and seawater for treatment of red mud have been studied in detail. This paper is based upon and emph...
Lecture Notes in Civil Engineering, 2023
Red mud is also known as bauxite residue, an industrial by-product obtained during the processing of bauxite into alumina. The produced red mud is usually disposed of on land and water bodies, leading to various environmental issues. Red mud is composed of fine particles, various chemical constituents and minerals. It cannot be utilized mainly due to its high alkalinity and the possible presence of heavy metals. Moreover, low hydraulic conductivity, extreme corrosive in nature, high water holding capacity, low shear strength, longer consolidation time, high salinity, lack of plant nutrients, and very low organic content are the other major concerns with red mud. Hence, red mud is to be utilized as an amendment or adsorbent in various engineering applications. There is a serious emergency and a lot of scope to study various physiochemical, mineralogical, and geoenvironmental properties to pave a path to utilize red mud in various applications such as treatment of wastewater, acid mines, reducing swelling of soils and as an amendment for clay liner preparation. This paper aims to review and highlight the applications of red mud as an amendment, adsorbent, catalyst, and coagulant to remove pollutants/contaminants in soil or water.
Characterization and applications of red mud from bauxite processing
K e y w o r d s Red mud, pigment, bauxite A b s t r a c t This work describes the characterization of red mud – a waste generated by the Bayer process in the aluminium industry – which causes environmental problems. Residue of the alumina leaching from bauxite was analyzed for mineral compositions of the mineral ore and its residue for chemical composition, density, and grain-size composition. The residue was calcinated and finally tested as a pigment for use in the building material industry. The test blocks were tested on the compressive strength.
2014
Red Mud coming from Tanrai Alumina Processing plant, Lamdong, Vietnam contains high excess alkaline component and many toxic heavy metals. The results showed that Red mud does not contain artificial radioactive isotopes such as 137 Cs, 7 Be; concentration of Uranium, Thorium in Red mud are less than the average concentration values of Uranium (2ppm) and Thorium (12ppm) in the earth's crust; annual effective dose caused by gamma radiation is smaller than the average effective dose was recommended by UNSCEAR. Physical texture of Red mud classified by equilateral triangle are sandy loam (57.1% sand; limon 33.8%; clay 9.1%). Chemical composition of Red mud is, by weight (% w/w): Fe 2O3 - 30.8; SiO2 31.7; Al2O3 - 15.6; TiO2 - 2.58; Na2O - 3.14, CaO - 3.51; K2O - 0.11; MgO - 0.27; MnO - 0.02; P2O5 - 0.22. Red mud also contains some heavy metals and have pHH2O and pHKCl are 11.23 and 11.12 respectively. The seearch results are an important basis to orient treatment and recovery this so...