Hydroxymethyl diphosphonated polyacrylates for red mud treatment

摘要

The invention comprises a process for improved flocculation of Bayer process red mud-containing slurry. The improvement comprises adding to the red mud-containing liquor a hydroxymethyl diphosphonic acid polymer optionally in addition to the conventional flocculant. The polymer is added to the red mud-containing liquor in an amount sufficient to reduce the concentration of suspended solids in the supernatant phase and/or increase the rate of sedimentation.