FIELD: process engineering.
SUBSTANCE: invention relates to nonferrous metallurgy. Alumina-bearing stock is leached to obtain aluminate solution and red mud to be separated from the former and fed for crystallisation for producing mother solution and precipitate including aluminium hydroxide. Aluminium hydroxide is subjected to calcination for production of alumina. Crystallisation is performed at 25-39°C by adding aluminium sulphate to aluminate solution in amount of 0.5-5.0 wt % of aluminium oxide content in aluminate solution. Obtained aluminium hydroxide is subjected to crystallisation at seed ratio of 0.1-0.4.
EFFECT: higher yield, faster process.