Advances in selective flocculation technology for solid-solid separations

Selective flocculation is a potential process for solid-solid separations in the fine particle size range. The critical barriers to further the commercial applications of this technique are loss in predicted single mineral selectivity in mixed mineral systems, extrapolation of mixed mineral selectivity to natural systems, and scale tip from laboratory to plant. A comprehensive review of the recent advances in selective flocculation technology, which facilitates overcoming these barriers, is presented in this paper. These include identification/design of selective reagents based on the surface chemistry of particles, use of site blocking agents to minimize heteroflocculation, and tailoring the polymer characteristics vis-a-vis particle size to achieve the desired separation efficiency. (C) 2000 Published by Elsevier Science B.V. All rights reserved.