A press release from Norsk Hydro confirms that the federal environmental agency IBAMA authorised alumina refinery Alunorte on October, 5th, to utilize its state-of-the art press filter technology in the processing of bauxite residues. This will extend the life of its DRS1 bauxite residue disposal area and allow Alunorte to continue operations on safe conditions. After getting green signal from IBAMA’s, Alunorte will now have to obtain authorization from SEMAS, Secretary of State
The new filter presses will deliver environmental benefits by moving the refinery to dry stacking of bauxite residue and extend the life of the operation, which supports 1,000 jobs in the Saguenay-Lac-St-Jean region. The presses will ramp up to being fully operational in early 2020.
Bauxite residue (BR) is a rather unknown, in the engineering field, secondary material. BR, also known as red mud, is the remainder of bauxite treatment according to the Bayer process. This secondary material, usually in a semi-fluid state, is produced in big quantities at the aluminium production industrial plants worldwide. Estimates raise global annual production of BR to 150 million tons. International literature indicates that the largest part of the by-product is disposed following
Bauxite Residues (BR) Dewatering BR in Filter Presses The filter cake has a moisture content to 25%, which makes it easier to handle AoG was one of the first Western European plants to apply this technology AoG Produces 650,000 t BR per year Can this BR cake be a potential resource? 5.
Four 85 t presses have been installed at the refinery using the latest in filter press technology. Industrial filtration consists in applying a mechanical pressure to dry bauxite residue, making it easier to store. The new presses will dry residue in only 17 minutes, instead of the three years it takes currently.
A new step in the Bayer process has been used to recover NaOH and to reduce its content in red mud. After digestion, the residue is separated from the Bayer liquor and goes through press filters, which enables the recovery of NaOH and decreases the moisture content. It is well known that red mud is one of the most important sources of scandium. Author: Amilton Barbosa Botelho Junior, Denise Crocce Romano Espinosa, Jorge Alberto Soares TenórioPublish Year: 2021People also ask How is bauxite used as a filler in cement? Opportunities for bauxite residue as a filler in blended cements have been explored, sometimes for their pozzolanic activity but also to improve the mechanical properties in blended cement by other mechanisms such as optimising packing density or rheological characteristics. bauxite.world-aluminium.org/refining/bauxite-residue-utilisation/ How much Bauxite is used to make clinker? The best estimates are that between 1,000,000 to 1,500,000 tonnes of bauxite residue are currently used annually in the production of clinker. The cement plants currently utilising the bauxite residue in clinker production are based in China, Ukraine, India, Russia, Georgia, Moldova and Greece. bauxite.world-aluminium.org/refining/bauxite-residue-utilisation/ How is bauxite residue used to build roads? When dewatered, compacted and mixed with a suitable binder, bauxite residue makes a good road building material and has been used to construct haul roads on bauxite residue areas for very many years. bauxite.world-aluminium.org/refining/bauxite-residue-utilisation/ How much Bauxite is used in Portland cement? The iron and aluminium constituents of the bauxite residue provide valuable additions in the production of Portland cement at a low cost. The best estimates are that between 1,000,000 to 1,500,000 tonnes of bauxite residue are currently used annually in the production of clinker. bauxite.world-aluminium.org/refining/bauxite-residue-utilisation/ icsoba.org › assets › filesand filter presses and solar drying. Filter press technology has advantages that make it particularly suitable for bauxite residue treatment. Compared to other technologies, filter presses allow drier residue (with residual moisture lower than 30% w/w). As a consequence, the material handling characteristics of the cake obtained by using filter