improved process for fluidifying flocculated aqueous suspensions of red muds in the production of alumina from bauxite by the bayer process , which consists : in dissolving bauxite using sodium hydroxide ; then , in decanting and in washing the red muds formed in order to separate them from the alumina in successive vats , while recycling the washing waters upstream ; and finally , in eliminating the red muds thus treated ; and in which a flocculant consisting of a polyacrylamide of molecular weight greater than ten million is introduced into the suspension of one of the successive vats ; wherein a dispersing agent formed by an anionic acrylic acid polymer of molecular weight lower than fifty thousand is added simultaneously with said flocculant to the suspension in the same vat .