The presence of unwanted coarse material in flotation feed streams has negative impacts on both recovery and throughput of concentrator plants. Detection of this coarse material is a long-standing problem in mineral processing that has been poorly addressed by existing instrumentation systems.

Two novel and robust technologies have been developed to address this challenge of unwanted coarse material in the individual hydrocyclone overflow streams that jointly become the flotation feed stream. This coarse material creates adverse effects in the flotation process and, sometimes, further downstream in the tailings thickening process. These technologies were developed and tested at a large North American copper concentrator where they continue to operate commercially for several years. Data from these installations has been previously presented.