Iron ores processing waste materials utilization in soft-mud molding ceramic bricks production

Abstract

The issues of iron ores processing secondary products utilization in combination with other industrial wastes for the needs of wall ceramic materials production technology are considered. Utilization of the studied iron ores processing wastes in ceramic technology is based on iron oxides ability to sustain ceramic materials sintering process with liquid-phase presence in significantly lower temperatures. Phase composition of the Abakanskoye deposit iron ores processing wastes, following their two-stage dry magnetic separation, and that of aluminium production gas treatment residue, were studied by means of up-to-date methods. Iron ores processing wastes are represented by magnetite, hematite-magnetite, chlorite-magnetite, quartz-carbonate-magnetite associations. Gas treatment residue consists of metamorphized coal particles of graphite, cryolite, chiolite, alumina, fluorite, nepheline, diaspore. They provide reducing medium in ceramic sintering, contrib- uting to transition of iron compounds into ferrous state. Using iron ores processing tailings masses as a component provides for a considerable increase (by 30–40 %) in strength properties of specimens. Addition of mineralizer, based on aluminium production gas treatment residue, to iron ores processing tailings, provides for formation of melt with low dynamic viscosity at 850 ° С, leading to increase in specimens’ strength by 150–180 %. Increase of products’ durability in service owing to introduction of tailings materials is based on shift of free waterrapid freezing point to lower temperature range by 2–10 °С, and its complete freezing – by 25–55 °С. A flow sheet has been developed for industrial wastes preparation for utilization in ceramic bricks production technology, currently applied at operating ceramic brick-making plants.