Solid state and phase transformation mechanism of kaolin sintered with limestone for alumina extraction

Microstructural Master Alloys Features of Aluminum–Erbium System

“…Thus, it seems relevant to develop new technological solutions for the production of aluminum-erbium master alloy systems. It should be mentioned that for the domestic industry, the state's priority is to stimulate the improvement of the technical level of production of Russian companies in order to increase the efficiency of processing raw mineral materials [26][27][28][29][30], including magnetite-hematite, kaolin and polymetallic ores [31][32][33], needle coke [34,35] oil and marine fuels [36][37][38].…”

Enhanced alumina extraction from kaolin by thermochemical activation using charcoal

“…The alumina content is then efficiently extracted from these calcium aluminate compounds by the hydrometallurgical leaching process using sodium carbonate solutions followed by washing with hot distilled water and then the filtration processes given to the resulting white sludge. The produced white sludge has good chemical and physical composition making it suitable for 5 the production of the Portland cement (Chou & Burnet, 1981;Ptáček et al, 2013;Al-Ajeel et al, 2014;Zhang et al, 2015a;Sizyakov, 2016;Tian et al, 2016a;Stange et al, 2017;Azof et al, 2019;ElDeeb et al, 2019;ElDeeb et al, 2020a).…”

“…It is worth noting that the lime-sinter is the lowest cost-effective, timesaving and energy-efficient method for alumina extraction from kaolin at 1360 ºC, when compared with the other pyro-hydrometallurgical (i.e., the Bayer and the soda-lime sinter) methods (ElDeeb et al, 2019(ElDeeb et al, , 2020a. These positive effects and advantages of the lime-sinter process are as a result of the crystallographic transformation of the dicalcium silicate (C 2 S) from β to γ phases during the cooling stage, the resulting sinter is self-disintegrated into a highly desirable ultrafine powder with a higher surface area, and therefore no pre-leaching grinding is required, that produced to a high leaching performance with a minimal low reagent consumption (Al-Ajeel et al, 2014;Pak et al, 2019;ElDeeb et al, 2019ElDeeb et al, , 2020a.…”

“…In ElDeeb et al, 2019ElDeeb et al, , 2020a, the self-disintegration process by sintering kaolin using the lime-sinter process at 1360 ºC is consider cost effective, energy effective and time saving process and therefor, the resulting sinter is not necessary to be grinded before leaching process. Therefore, an achieving of the thermochemical activation by the addition of fluxing agents (i. e. Charcoal) to the kaolin-limestone mixtures in the sintering process would produce more low costeffectiveness and energy-efficiency by lowering the temperature limit of the phase transformation (i.e., dicalcium silicate C 2 S β to γ phases).…”

Experimental Study of Harmonic Influence on Electrical Energy Metering

“…Currently, in many industrial enterprises, the main share in the cost of production accrues from electricity consumption costs [1][2][3]. This is particularly true for energy-intensive enterprises in the aluminum industry [4,5]. For instance, electricity consumption by the Bratsk Aluminum Smelter reaches 75% of the electricity generated at the Bratsk Hydroelectric Power Station, the installed capacity of which is 4500 MW [6].…”