Effects of new flocculants on settlement of Bayer red mud

A series of experiments on Bayer red mud generated from Chinese diaspore bauxite were performed using experimentally-synthesized new flocculants ASAM (obtained from acryamide, sodium acrylate and β-methylhydrogen itaconate) and commercial flocculants PAS-3, 0228 and Alclar665, respectively. The effects of intrinsic viscosity and addition of ASAM on settling performance were investigated. The influence of red mud with different solid contents on settlement was also discussed. The results show that the flocculating performance of the ASAM is excellent, its settling rate for red mud is almost equal to that of 0228, and apparently superior to that of PAS-3 and Alclar665. The clarification performance of ASAM is better than that of Alclar665. When the ASAM with 100 g/t dosage is added to the red mud slurry whose concentration is 108.4 g/L, the average settling rate of red mud in initial five minutes is 1.22 m/h and the liquid solid compression ratio of the supernatant is 2.86, lower than others.