Hydrocyclone Circuits

Abstract

A number of plant surveys have shown that hydrocyclones used for classification have significant problems with respect to the efficiency of size separation and the particle density effect. The issues of minimizing the amount of ultrafines and maximizing the amount of light coarse particles in the oversize flowstream require conflicting operational approaches with a single cyclone. Earlier modelling work suggested that the Three Stage Counter Current Cyclone Circuit was able to provide the best mechanism for addressing these issues compared to a single cyclone. In order to evaluate the potential of this type of circuit, a pilot-scale investigation program was initiated. This involved identifying the relationship between the key control variables and response variables in order to optimize the circuit. This circuit has been shown to achieve the following: ” A much sharper separation with a low level of ultrafines in the oversize stream due to two stages of cycloning. ” Marked reduction in the amount of misplaced coarse clean coal in the undersize flowstream. ” Reduction in the amount of ultrafine pyrite in the oversize flowstream. ” Lower separation sizes without impacting efficiency.