SIDERITIC ORE PROCESSING METHOD (VERSIONS) Russian patent published in 2014 - IPC C22B26/22 C22B1/02 C22B3/06 B03C1/05 

FIELD: mining.

SUBSTANCE: inventions (versions) relate to processing of high-magnesia sideritic ores. Methods involve crushing and sieving of base ore, magnetising annealing under conditions without any supply of atmospheric oxygen for decomposition of iron and magnesium carbonates, dry magnetic separation, final crushing of the extracted magnetic fraction and leaching out of it of magnesium oxide by means of a carbonic acid solution. Then, heating of the solution obtained after leaching is performed to the temperature providing extraction of magnesium carbonate from it, and further decomposition of magnesium carbonate to magnesium oxide by heating above 650°C is performed. With that, as per the first version, annealing is performed at the temperature of 500-700°C; after that, activation is performed at 400-700°C by water vapours with further cooling. An activated product is subject to magnetic separation, and leaching is performed during 30-60 minutes out of the 0.2-0 mm fraction. As per the second version, annealing is performed at the temperature of 500-700°C; after that, activation of the annealed product is performed by its cooling to the temperature below 100°C, and then, by heating of the cooled product up to 350-500°C and further isothermic exposure during 60-90 minutes. An activated product is subject to magnetic separation, and leaching is performed during 30-60 minutes out of the 0.2-0 mm fraction.

EFFECT: proposed versions allow obtaining two high-quality products: iron-ore concentrate with iron content of 60,3% and magnesium oxide with purity of at least 98%.

2 cl, 4 tbl