A review on the potential uses of red mud as amendment …
Red mud is a solid waste of bauxite processing by Bayer process which involves caustic digestion of Al-containing mineral for alumina production. The global inventory of red mud waste reached an estimated amount of 4 billion tons in 2015, increasing at an approximate rate of 120 million tons per year. Therefore, its management is becoming a global environmental …
Efficient utilization of red mud waste via stepwise leaching …
Four components, including Fe 2 O 3, CaO, Al 2 O 3, and SiO 2, constitute the major part of red mud. One of the most challenging steps was to choose a method to separate calcium from the mixture.
Progress on the Industrial Applications of Red …
Red mud (RM), also called bauxite residue, is a strong alkaline industrial waste generated during the alumina production process. The annual production of RM in China is large, but its average utilization rate is low (only …
Characteristics – Red Mud Project
Under the alkaline oxidative conditions existing in the Bayer process, they break down to more simple compounds such as the sodium salts of succinic, acetic and oxalic acids. Predominant among these salts is sodium oxalate. ... Red mud in "as it is" state, solid concentration ~400g/l . Red mud after water evaporation. Bibliography. W ...
The Use of Waste Materials Red Mud and Fly Ash as Road
The main components of red mud include Fe 2 O 3, Al 2 O 3, SiO 2, Na 2 O, and CaO, along with trace amounts of Th, U, Y, ... In this incident, the highly alkaline red mud (approximately pH 12) caused a catastrophic flow, resulting in the deaths of 10 people, injuries to hundreds, and the destruction of around 40 km 2 of farmland [15,16].
Characterization and Applications of Red Mud, an …
The disposal of red mud (RM), a waste material generated by the aluminum industry, remains a global environmental concern because of its high alkalinity and smaller particle size, which have the potential to pollute air, soil, …
Study on occurrence form and solidification mechanism of …
The results show that: (1) The alkaline components in the red mud are mainly Na components, and the soluble Na components are mainly in the form of NaHCO3 and …
Application of microbial mineralization in the treatment of …
Red mud is a highly alkaline solid waste with very fine particles produced in the production of alumina from bauxite, which is difficult to utilize comprehensively.
(PDF) U Effect of Alkaline Activator on the Main Properties …
When the alkali activator is RF, the replacement of glass powder with 25% red mud powder determines an increase (with 15-) of the compressive strength values; this opposite influence (as compared with the system activated with NaOH solution) can be explained by the ability of red mud powder (R) to continuously release alkaline ions in RF ...
Characteristics – Red Mud Project
Under the alkaline oxidative conditions existing in the Bayer process, they break down to more simple compounds such as the sodium salts of succinic, acetic and oxalic …
The Study of the Magnetic Properties of Red Mud from …
In Russia, the main feedstock for producing aluminum is bauxite. During the processing of 1 ton of bauxite into alumina (Al 2 O 3 ), up to 0.5–0.6 ton of techno-genic waste is formed, that is ...
Article Research on High Pressure Hydrochloric Acid …
The typical contents of valuable components in red mud such as Ti, Si, Fe, Na and Al ... the iron‐depleted red mud [31]. The main pyrometallurgical ways for iron recovery from red mud are ...
A Review on Comprehensive Utilization of Red …
Red mud contains high quantities of alkali-generating minerals and metal ions, which can cause significant environmental damage. Many valuable components such as rare-earth elements, Al, and Fe, in RM are difficult to …
Efficient utilization of red mud waste via stepwise leaching to …
Four components, including Fe 2 O 3, CaO, Al 2 O 3, and SiO 2, constitute the major part of red mud. One of the most challenging steps was to choose a method to separate...
Summary of research progress on separation and extraction …
In the industrial production of alumina, there are three main production methods: the Bayer process, sintering process, and combined process (Liu et al. 2014a).The Bayer process is the most commonly used in alumina production (Liu et al. 2007), and more than 90% of alumina is produced by the Bayer process worldwide (Wang et al. 2018).Bayer red mud is an insoluble …
Dealkalinization Effect of Carbon Dioxide in Flue Gas on Bayer Red Mud …
Table 1 showed that Fe 2 O 3, SiO 2, Al 2 O 3, and TiO 2 were the major chemical components of red mud, and their contents were 39.79%, 21.51%, 16.32%, and 3.65%, respectively. In addition, the content of CaO was 2.24%, while the content of the key alkaline substance, Na 2 O, was as high as 3.29%.. Figure 1 suggested that hematite was the iron-bearing mineral, …
Study on occurrence form and solidification mechanism of alkaline …
Abstract. Red mud contains excessive Na +, which seriously damages acidity and alkalinity of surrounding soil and groundwater.Therefore, the occurrence form and the leaching characteristics of the alkaline components in red mud under different pH conditions were studied by X-ray diffraction (XRD), ion chromatography and titration test, et al., and the solidification …
Separation and recovery of titanium and scandium from the red mud
Alkaline leaching of red mud typically aims to recover sodium and aluminum [32]. The dissolution efficiency of titanium and REEs have been shown to be low with alkaline leaching treatment. In contrast, recovery rate of these components has been shown to be sufficiently high using acidic reagents. ... The concentration of major components of the ...
An Eco-Friendly Acid Leaching Strategy for Dealkalization of Red Mud …
The alkaline components in red mud represent one of the crucial factors restricting its application, especially for the construction and building industry. ... Therefore, the main reason accounting for the phase transformation is the combination of the active component (e.g., SiO 2 and Al 2 O 3) and sodium aluminosilicates at high temperatures ...
Synthesis and properties of new materials produced by alkaline …
Red mud is a waste generated in Bayer process during the treatment of bauxite with caustic soda for alumina extraction (Grafe et al., 2009). This slurry is, in general, strongly alkaline (pH range from 9.7 to 12.8; Grafe et al., 2009) and contains a wide range of minerals classified in two groups: i) mineral phases present in the original bauxite, unchanged by the …
Characteristic, hazard and iron recovery technology of red …
Red mud (RM) is the major waste material with strong alkaline discharged which is during the alumina extraction process. The global stock of RM has exceeded 4 billion tons …
Staged leaching behavior of red mud during dealkalization with mild
The alkaline components in red mud represent one of the crucial factors restricting its application, especially for the construction and building industry. ... The main components of the filter ...
Applications of Red Mud as a Masonry Material: A Review
Red mud (RM) is a highly alkaline by-product produced by the aluminium industry. The total stockpile of RM in the world is evaluated to be close 4 billion tons, which caused serious soil and water pollution. ... The main components of RM resulting from the Bayer process are haematite (Fe 2 O 3), boehmite (γ-AlOOH), ...
Red mud is piling up. Can scientists figure out …
The team hopes red mud could become a source of both the extra iron added to their cements and the alkaline compounds needed to catalyze the hardening reactions. ... and even fertilizer. Yet just 3% of red …
Enhanced performance of red mud oxygen carrier for …
Among, Red mud (RM), a by-product of bauxite processing through the Bayer process, exhibits characteristics of strong alkalinity (pH 10–14), a large quantity, and complex components [19, 20]. Fe 2 O 3 is the main component of red mud, typically accounting for 15–60 wt%, and it is considered as potential OCs. It is noteworthy that the raw ...
Red mud: Characteristics, utilization, and environmental …
RM-ERMs find application in three main areas: purifying wastewater, treating atrophy gases, and remediating soil. The extremely alkaline nature of red mud is harnessed …
Study on the Acid Leaching of Metal Components in Bayer Red Mud …
Materials. The red mud sample used in this experiment was collected from an alumina refinery in Henan province, China. The chemical element composition of red mud sample was analyzed, and the result was illustrated in Table 1.It can be seen from Table 1 that the Fe 2 O 3 content in the red mud sample is 25.915%, the Al 2 O 3 content is 19.447%, and …
Utilization of Red Mud as Sustainable Material: A State of
Global red mud production ranges between 120 million tons per year, with India accounting for 10% of global red mud production . Red mud or alkaline residue refers to the solid waste produced after processing bauxite ores with caustic soda to produce alumina (Al 2 O 3) . The methods used to dispose of red mud differ from country to country.
Characteristic, hazard and iron recovery technology of red mud …
Generally,the main chemical components of RM include Al 2 O 3, Fe 2 O 3, SiO 2, TiO 2, ... (Zhang et al., 2020), and the highly alkaline red mud could cause severe chemical burns to humans and animals and kill creatures in the rivers and contaminate soils. Thus, it is crucial to dewater, ...
Application of microbial mineralization in the treatment of …
Red mud is a highly alkaline solid waste with very fine particles produced in the production of alumina from bauxite, which is difficult to utilize comprehensively. In this paper, microbial mineralization is applied to the treatment of sintering red mud, and the mineralized products with good cementation characteristics generated in the reaction process are used to …