Method and an electrochemical installation for treating aqueous effluent containing a heavy metal

An electrochemical installation for treating aqueous effluent containing a heavy metal, the installation comprising an electroplating reactor for the heavy metal, itself comprising a tank in which alternating electrodes of opposite polarity are placed, the cathodes being removable volume electrodes each constituted by a cassette in the form of two facing frames each supporting a wall that is permeable to said aqueous effluent, the permeable walls of a single cathode defining a space that is filled with an active granular material and in which a metal current-feed grid is disposed. According to the invention, the installation further comprises a regeneration electrochemical reactor for receiving the cathodes as anodes, the metal constituting the metal current-feed grids being selected from metals having an oxidation-reduction potential greater than that of the heavy metal to be electroplated and enabling the end of regeneration to be detected. The invention is applicable to depolluting aqueous effluent polluted by waste containing heavy metals.