The effect of some design and operating parameters in the cyclo-column cell

Abstract

Cyclo-column cell is a flotation device which makes use of centrifugal force for bubble-particle contact and incorporates a froth column with optional wash water to provide a clean froth product. In this study, the influence of certain design and operating variables (froth column type, number of feed pumps, inset length, froth column height, air flowrate and wash water) on the performance of the cyclo-column cell was examined. It was found that the froth product obtained from the device could be rendered substantially cleaner by employing an expanded froth column which permits effective drainage of pulp from the froth and minimizes entrainment of undesired minerals. For example, in the reverse flotation of a magnetite ore, the froth product (tailings) grade dropped from 15.07% Fe in the case of a straight froth column to 8.72% Fe with an expanded froth column of the same height. Application of wash water resulted in a further reduction of about 1.4% Fe in tailings grade. The use of a single feed pump, as opposed to two pumps working in series, produced a cleaner froth product but at a lower throughput. A froth column height of 205 mm and an inset length of 20 mm were found to be satisfactory; and an air flowrate of 20–25 scfh produced the best results in terms of tailings grade and flotation rate.