Tailings disposal using flocculantassisted hydrocyclones

CIM Bulletin, Vol. 89, No. 1005, 1996

Turgut Yalcin, School of Engineering, Laurentian University, Sudbury, Ontario

In this study, potential benefits of flocculant usage were explored in the processing of mill tailings by hydrocyclones. Tests conducted on copper-nickel mill tailings have demonstrated that, under suitable conditions, flocculation could significantly enhance solid-liquid separation in hydrocyclones. For example, at a feed pulp density of approximately 9%, flocculantassisted hydrocyclone produced an underflow with over 98% solids recovery, compared to a recovery of less than 53% with conventional hydrocyclone. However, feed pulp density was found to be a critical factor, and tailings with pulp densities of greater than about 15% required a two-stage hydrocyclone operation where the flocculant-assisted hydrocyclone was employed at the second stage to process the overflow of a conventional hydrocyclone. The underflow and overflow products obtained from the flocculant-assisted hydrocyclone may be discharged into tailings dams in the same manner as those produced by gravity thickeners. The flocculant-assisted hydrocyclone would, however, provide a higher throughput.