METHOD OF LEACHING BAUXITE Russian patent published in 1997 - IPC

FIELD: mining industry. SUBSTANCE: invention is dealing with silica production via autoclave leaching of bauxite. Method is performed by way of pumping through bauxite slurry through slurry-slurry heat exchangers in two heating steps in different heat exchangers. In the first step, as heat carrier, leached slurry from second-step separator is utilized, and in the second step, leached slurry from first-step one. Leached slurry is cooled in the second-step heat exchangers to a temperature higher than its boiling temperature in the second autoevaporation step, and in the first-step heat exchanger to a temperature below its boiling temperature at atmosphere pressure. Slurry is then successively heated in steam-slurry heat exchangers, heating, and reaction autoclaves. At last, leached slurry is loaded into the first- and second-step separators. Vapor from second-step separator is utilized to heat industrial water, and leached slurry is loaded into agitator. EFFECT: enhanced efficiency of process. 1 dwg