Bauxite residue in cement and cementitious applications: Current status and a possible way forward

The History, Challenges, and New Developments in the Management and Use of Bauxite Residue

“…Due to its high iron and aluminium oxide content, it can be, in an appropriate manner, treated or with other iron ores, be smelted to iron.'' Possible applications can broadly be broken down into various categories: • recovery of specific components present in the bauxite residue, e.g., iron, titanium, aluminum, lanthanides, scandium, yttrium, and gallium [17,18]; • use as a major component in the manufacture of another product, e.g., cement [19][20][21]; • use of the bauxite residue as a component in a building or construction material, e.g., concrete, tiles, bricks [22]; • use for specific properties, e.g., soil amelioration or landfill capping [22]; • conversion of the bauxite residue to a useful material by modifying the compounds present, e.g., Virotec process [23][24][25].…”

“…Some of the most attractive areas have been: cement manufacture [19][20][21]28], use in concrete, iron recovery [30,34], titanium recovery [17], use in building panels, bricks, foamed insulating bricks, tiles, soil amelioration, refuse tip capping/site restoration, treatment of acid mine drainage [23][24][25], soil amelioration, road construction [27], dam/levee construction, pigments, and glass ceramics. Meanwhile, some other uses which have been shown to be technically feasible but not yet exploited to any significant degree are lanthanides (rare earth elements) recovery, scandium recovery, gallium recovery, vanadium recovery, cobalt recovery, yttrium recovery, adsorbent of heavy metals/ dyes/phosphate/fluoride, water treatment chemical, ceramics, foamed glass, oil drilling or gas extraction proppants, gravel/railway ballast, calcium and silicon fertilizer, filler for PVC, wood substitute, geopolymers [45], catalysts [40], plasma spray coating of aluminum and copper, manufacture of aluminum titanate-Mullite composites for high temperature-resistant coatings, composites with epoxides, composites with poly aniline, manufacture of radiopaque materials for the construction of X-ray diagnostic and CT scanner rooms, catalyst for hydrocarbon cracking, desulfurisation of flue gas, arsenic removal, and chromium removal.…”

Synthesis and Mechanical Characterization of Iron Oxide Rich Sulfobelite Cements Prepared Using Bauxite Residue

“…John and Ângulo 4 described the steps one should follow to find good use of any solid residue as: the residue characterization, the choices of use; market, economic and environmental analyses. Therefore, the characteristics of BR -as a fine powder rich in iron, aluminum and silicon oxides, nevertheless with high sodium content -have awaken the interest of some industrial sectors in using it mainly in cements for civil construction 5 . The first reason for that is due to its physical and chemical compatibility, which makes of it an interesting raw material choice.…”

“…Other proportions of the constituents that have less C 4 A 3 S and more C 2 S and C 4 AF do not present so significant environmental and technical advantages, but allow expressive reduction in cost, enhancing their economic viability. Following this trend some studies have investigated the use of BR as one of the raw material for the synthesis of sulfobelitic clinker 5,18,22,23 . Singh et al, investigated the synthesis of iron rich sulfobelitic cement using: hydrated lime 45-50 wt-%, BR 30-35wt-%, bauxite 15-20wt-% and gypsum 7.5-10wt-%.…”

“…At a proper proportion between BR and bauxite in the raw meal, it was synthesized a clinker majorly composed of C 4 A 3 S, C 4 AF and C 2 S. By adding 30wt-% of gypsum to this clinker, the resulting cement reached high early mechanical strength and later strength similar to Portland cement 22,23 . Even industrial trials of Lafarge are already trying to produce a sulfobelitic cement, by the name "Aether TM ", and at least in one of their patent BR is mentioned as a potential raw material 5 .…”