Study of the Processes of Obtaining Iron-Free Raw Materials from Ash and Slag Waste from the Combustion of Brown Coal of KAFEC
V. F. PAVLOV1, V. F. SHABANOV2
1Special Designing and Technological Bureau “Nauka”, Krasnoyarsk Scientific Centre of the Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk, Russia
2Federal Research Centre, Krasnoyarsk Scientific Centre of the Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk, Russia
Keywords: золошлаковые отходы, восстановительное плавление, магнитная и немагнитная фракции, кипящий слой, бурые угли, карбид кремния, силицид железа, вспенивание расплава, углетермическое восстановление, ash and slag wastes, reducing melting, magnetic and non-magnetic fractions, boiling bed, brown coal, silicon carbide, iron silicide, melt foaming, carbon thermal reduction
Pages: 343-348
Abstract
The processes involved in obtaining iron-free X-ray amorphous aluminosilicate raw material of the required composition from the ash and slag waste (ASW) from the combustion of brown coal of KAFEC are investigated. Carbon thermal reduction during ASW melting is used to extract iron and its compounds. The distribution of elements - iron (Fe2+, Fe3+, Fe0, Fetot), sulphur (S) and carbon (C) - in the metal (magnetic) and silicate (nonmagnetic) fractions at different temperatures of ASW heating is shown. The equations describing the temperature dependence of the standard change of Gibbs energy for the reactions of the reduction of iron oxides are presented. The effect of silicon carbide, formed in the silicate fraction of the melt, on the recovery of iron oxides to metal iron and the resistance of foam formed due to the reducing gases are discussed. The introduction of the melt into water changes the morphology and leads to the formation of foamed heat-insulating material. Normalization of the charge during melting allows obtaining foamed materials of the required composition.
DOI: 10.15372/CSD2019149
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