Alumina Hydrate Production

The stage in Bayer process alumina refining in which aluminium hydroxide crystals are precipitated from supersaturated sodium aluminate liquor through cooling and the addition of seed crystals. Hydrate production rate and crystal size distribution are controlled by adjusting precipitation temperature, seed addition rate, and liquor supersaturation. These parameters directly influence calcined alumina yield, particle size, and quality specifications required for smelting.