WEBOct 21, 2016 · Red mud is a slimy caustic residue generated from alumina refining of bauxite ores. During the alumina extraction process, about 35 %–40 % of the bauxite ores go into the residue as highly alkaline red mud slurry (pH –) which contains 15 %–40 % of solid phase in volume [1, 2].
WhatsApp: +86 18203695377WEBDec 1, 2009 · The sodium leaching ratio (ηN) of ferric bauxite direct reduction process is much lower than that of ordinary bauxite; thus, the former consumes more sodium than the latter. hN can be promoted by ...
WhatsApp: +86 18203695377WEBDec 15, 2021 · This work evaluates the characteristics of calcium aluminate slag and pig iron samples obtained from the smelting of calcined and reduced diasporic bauxite ore. The study is conducted in the Pedersen process framework, which is a method to produce alumina from lowgrade resources. Parameters such as .
WhatsApp: +86 18203695377WEBThe Pedersen Process is an alternative process for the production of alumina. Initially, bauxitelt;brgt; ores, or other aluminous materials, are smelted with lime and fluxes to produce pig iron andlt;brgt; a slag of mainly calcium aluminate composition.
WhatsApp: +86 18203695377WEBNov 1, 2023 · Aluminum demand has increased with modernization of our society. As the primary source of aluminum is bauxite ore, this has resulted in more accumulation of bauxite residue. A bauxite residue typically contains 15–25% of alumina depending on the origin of its ore and process conditions. Along with alumina, it also contains iron, .
WhatsApp: +86 18203695377WEBMar 8, 2021 · Metallurgical grade alumina is produced worldwide through the wellknown Bayer process, which unavoidably generates bauxite residue (BR, also known as red mud) in almost equal amounts to alumina. This study aims the valorization of BR through a smeltingreduction process to obtain calcium aluminate slags that can be a proper feed .
WhatsApp: +86 18203695377WEBSep 1, 2022 · Bauxite residue poses an increasingly serious ecological safety problem in the alumina industry. A novel process for removing sodium in bauxite residue synergistic preparation of potassiumcontaining compound fertilizer raw materials was proposed to relieve pressure on the fertilizer industry.
WhatsApp: +86 18203695377WEBMay 19, 2020 · A brief insight into the conventional Bayer bauxite digestion process demonstrates that during the low temperature digestion, gibbsite and clay minerals of bauxite gets dissolved, with formation of sodalite as one of the end reaction product. ... Hydration products calciumsilie–hydrate (CS–H) and monocarboaluminate phases .
WhatsApp: +86 18203695377WEBOct 5, 2016 · Then, the resulting hydrogarnet was decomposed by CO 2 carbonation, affording calcium silie, calcium carbonate, and aluminum hydroxide. Alumina was recovered using an alkaline solution at a low temperature. ... Till now, despite the developments in utilizing the bauxite residue in Bayer process, only a few of them have .
WhatsApp: +86 18203695377WEBIn this process, the raw bauxite which is mixed is converted to calcined bauxite. The following reaction takes place Al 2 O 2 O → Al 2 O 3 + 2H 2 O (at 1300 deg.) Other materials that can be calcined in this unit are clay, fireclay, etc. The calcination unit can be divided into 5 parts: Raw material crushing and storage; Kiln and cooler ...
WhatsApp: +86 18203695377WEBFeb 5, 2021 · This review covers the composition characteristics of bauxite residue, and describes the Bayer process in detail, where emphasis is put on the formation of alkaline substances in bauxite residue and its release process in longterm storage. This review focuses on several typical processes for the management of bauxite residue alkalinity in ...
WhatsApp: +86 18203695377WEBApr 4, 2023 · Bauxite residue is a strongly alkaline solid waste which is generated by the alumina refining sector. This waste stream may represent a high risk to the surrounding environment during the storage process (Jiang et al. 2022; Wu et al. 2020).Consequently, there have been several investigations of methods relating to for the safe disposal of .
WhatsApp: +86 18203695377WEBMay 11, 2023 · The present study investigates the properties of H2reduced calciumadded bauxite residue, selfhardened pellets, and the feasibility of iron recovery through electrostatic and magnetic separa ...
WhatsApp: +86 18203695377WEBJul 25, 2018 · Lowgrade bauxite ores are not favorable in the conventional Bayer process for alumina production, as they are producing more bauxite residue (red mud) and accompanying lower alumina yield than highgrade ores. In the current study, the thermodynamics and characterization of calciumaluminate slags and pig iron .
WhatsApp: +86 18203695377WEBJan 1, 2010 · Four kinds of alumina leach slurry were prepared by the hydrochemical process to treat the bauxite, the Bayer process, the Bayer process with less lime, and the hydrochemical process to treat the Bayer red mud. ... (CaTiO 3), one is the direct reaction of sodium trititanate with calcium hydroxide, and the other is the conversion of kassite ...
WhatsApp: +86 18203695377WEBSep 1, 2021 · The bauxite residue sinter leach process (BRSLP) is a potential method of recovering sodium hydroxide and alumina from bauxite residue. In this research, bauxite residue lime sinters were characterised using a combination of quantitative Xray diffraction in conjunction with scanning electron microscopy as well as for leaching performance.
WhatsApp: +86 18203695377WEBMay 5, 2016 · Different ways for alkaline recovery of aluminum from bauxite residue are considered from the literature and examined in experiments. The advantages and disadvantages of a hightemperature digestion via Bayer process and sodalime sintering process are elaborated and compared. As a hybrid process, bauxite residue .
WhatsApp: +86 18203695377WEBJul 1, 2021 · The prevalent pH rebound phenomenon in the bauxite residue alkalinity regulation is primarily caused by the presence of alkaline minerals, including sodalite and cancrinite. Calcium ion is widely used to remove the free alkali for reducing the alkalinity of bauxite residue, but its underlying mechanism on alkaline minerals is still unclear.
WhatsApp: +86 18203695377WEBMar 28, 2020 · The Bayer Process is the dominant industrial method to produce alumina from bauxite ore. Due to the generation of large amounts of Bauxite Residue (red mud), an alternative method, called the Pedersen Process, is of our interest. This process makes use of a combination of pyrometallurgical and hydrometallurgical techniques in order to .
WhatsApp: +86 18203695377WEBKinetic Modelling of Different Bauxite Types in the Bayer Leaching Process. Živan Živković ...
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