Process method for producing aluminum hydroxide by seed decomposition of supersaturated sodium aluminate solution

Disclosed is a process for producing aluminium hydroxide by seeded decomposition of a supersaturated sodium aluminate solution, wherein stirring is only locally carried out at the bottom of a seeded decomposition tank with an intensity sufficient to maintain the aluminium hydroxide particles at the bottom of the seeded decomposition tank in a suspended state, in order to promote diffusional mass-transfer of the sodium aluminate solution with a high solid content and high molecular ratio at the bottom of the seeded decomposition tank, and prevent the aluminium hydroxide particles at the bottom of the seeded decomposition tank from producing precipitates.