Multiobjective optimisation of spiral concentrator for separation of ultrafine chromite

Chromite beneficiation plants generate large amount of tailings with significant amounts of ultrafine chromite minerals. In the present investigation, Box-Behnken experimental design was used to model the effects of feed rate, feed pulp density and splitter position on the performance of a spiral concentrator for separating the ultrafine chromite values from the plant tailings. Splitter position has a major influence on both grade and recovery of the concentrate fraction of spiral concentrator. Second-order quadratic models were used for describing the performance of spiral concentrator. Multiobjective optimisation of process parameters was carried out for achieving both in grade and recovery which were higher than 40% and 30% Cr₂O₃, respectively.