Tailings disposal using flocculantassisted hydrocyclones
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.