A comprehensive review on aeration methods used in flotation machines: Classification, mechanisms and technical perspectives
Junyu Wang, Liguang Wang, Hongzhi Cheng, Kym Runge
Abstract
Providing aeration is the primary purpose of a flotation machine. Novel flotation machines have directly driven significant developments in the aeration system. This paper provides a comprehensive review of the developments and evolution of bubble generation methods used in the flotation field. The gas-in-liquid dispersion mechanisms were extracted and linked to different aerator designs. The aeration methods used in flotation were classified into six major groups and further broken down into twenty sub-types. The gas dispersion characteristics and the practical engineering features of the aerators were then critically analyzed. Based on these, an evaluation scheme for aerator performance was proposed. It was suggested that three factors – technical capability, the reliability of operation, and economic viability – made up a successful aerator. When evaluating all various aerator types discussed in the current work, it was found that it was difficult for current techniques to achieve all three goals, which suggested the future direction for developing new aerators. The results benchmark an aerator operation in a flotation machine, and the resulting reflection of the current state of bubble generation systems spurs opportunities for the development of the next generation of aerators and flotation machines. The knowledge can be translatable to other areas of application of any three-phase system.