Process for the production of aluminium sulphate, starting from the residual slimes of plants for the anodic oxidation of aluminium, according to the reaction: 2Al(OH)₃ + 3H₂SO₄ Al₂ (SO₄)₃ + 6H₂O According to the process slimes (1) undergo a homogenizing treatment (2) which allows them to be subsequently conveyed up to and into the reactor (4).