{"id":490,"date":"2017-08-10T11:36:12","date_gmt":"2017-08-10T11:36:12","guid":{"rendered":"https:\/\/goodrichmagma.com\/demo\/?page_id=490"},"modified":"2017-12-05T05:10:34","modified_gmt":"2017-12-05T05:10:34","slug":"processing-of-red-mud-from-alumina-production-in-magma","status":"publish","type":"page","link":"https:\/\/goodrichmagma.com\/index.php\/processing-of-red-mud-from-alumina-production-in-magma\/","title":{"rendered":"Processing of red mud from alumina production in MAGMA"},"content":{"rendered":"

In the Bayer production of alumina, red bauxite sludge is produced as a by-product, which is a fine substance of the following composition, %<\/p>\n\n\n\n\n
Fe2<\/sub>O3<\/sub><\/td>\nCao<\/td>\nSiO2<\/sub><\/td>\nAl2<\/sub>O3<\/sub><\/td>\nMgO<\/td>\nTiO2<\/sub><\/td>\nS<\/td>\nP2<\/sub>O5<\/sub><\/td>\nNa2<\/sub>O<\/td>\n<\/tr>\n
40-55<\/td>\n8-11<\/td>\n5-15<\/td>\n14-16<\/td>\n0.5-1.4<\/td>\n2-5<\/td>\nup to 2<\/td>\n0.2-0.5<\/td>\nup to 2<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Moisture content in such product is 40-60%.<\/p>\n

For absence of efficient processing technologies, the main mass of red mud is not used and is stock-piled in special sludge storages that affect the environment badly. More than 100 million tons of red mud has been accumulated in Russia to date.<\/p>\n

The smelting \u00a0unit \u00a0MAGMA is applicable\u00a0\u00a0 for\u00a0\u00a0 pyro metallurgical processing of red mud by the method of liquid-phase reduction of iron oxides by carbon in one-stage process (Fig. 8), or by two-stage process, in combination with electrical arc furnace.<\/p>\n

The heat recovered from the body of the unit by the liquid-metal coolant is used for dewatering (drying) of initial red mud.<\/p>\n

Partially dried mud fed to the unit is smelted in a liquid slag bath. Iron\u00a0 oxides\u00a0 contained in red\u00a0 mud\u00a0 are\u00a0 reduced by carbon\u00a0 (coal)\u00a0 fed\u00a0 to the\u00a0 surface of\u00a0 the\u00a0 molten\u00a0 mass.\u00a0 Reduced iron in the form of cast iron settles down to the bottom of the unit.\u00a0 Composition of the re-smelted and reduced slag is adjusted by adding fluxes according to the type of its further use.<\/p>\n

Cast iron, raw material for additional recovery of alumina or clinker for production of alumina cement are the products produced in the one- stage route of red mud processing.<\/p>\n

In the two-stage process, ferro-silicon can be produced in addition to the above-mentioned products.<\/p>\n

Processing\u00a0 of\u00a0 red\u00a0 mud\u00a0\u00a0 by\u00a0 MAGMA\u00a0 is\u00a0 a\u00a0 completely waste-free technology, because the\u00a0 dust\u00a0 captured in the\u00a0 gas\u00a0 treatment system\u00a0 is recuperated by injectors to the smelting chamber of the unit to the molten\u00a0 slag.<\/p>\n

Production capacity of the standard model of MAGMA for processing red mud dried to moisture content 15% is 200,000-250,000 tons per year.<\/p>\n

Up to 0.35 tons of cast iron and up to 0.5 tons of alumina clinker can be produced out of 1 ton of processed red mud.<\/p>\n

Specific consumption of energy carriers for processing of 1 ton of red mud:<\/p>\n