Flocculation and Sedimentation of Bauxite Flotation Tailings

Flocculation and sedimentation of fine bauxite from flotation tailing pulp were studied using different flocculants to investigate the possibility of its application. The results of this investigation indicate that inorganic flocculants of PAC and PAS have better flocculating effect than organic flocculants of PAM1# and PAM2# when keeping the original pH (7.5~8.0) of tailing pulp, however its consumption are large. It was found that the pH of pulp is important to the tailings settlement. The dosage of flocculants are greatly reduced and the velocity of floc settling is accelerated when the pH of tailing pulp is adjusted to 6.5~7.0 using sulfuric acid. PAM1# and PAM2# are effective flocculants for fine bauxite from the tailings pulp and improved the sedimentation performance compared with PAC and PAS at pH 6.5~7.0. It was also found that the flocculants can be used in combination to treat original bauxite tailing, and good sedimentation effect has been achieved, but the dosage of reagents is bigger when the organic flocculant is combined with inorganic flocculant.