Numerical Simulation And Performance Research Of A Novel Column Flotation

Flotation method has a very wide range of applications in the field ofengineering, including mineral processing. This paper describes the mechanism of theflotation process, tells the history of the development of the flotation device, flotationmachine and flotation column. When comparing the advantages and disadvantages ofthese two flotation devices, the author gets the conclusion that the flotation columnhas an advantage of reducing energy consumption, which means, from the perspectiveof long-term development, the flotation column would have a good applicationprospect.This article uses computational fluid dynamics software FLUENT6.3.26tosimulate the flowfield in the multi-level structure packing flotation column(MSSPFC). In order to simplify the calculation process, a standard k-ε turbulencemodel was used to describe these two phases in the simulations, considering the dragforce for interphase momentum transfer only. The velocity of the circulating liquidand gas holdup distribution in the different radial positions are obtained through thesimulations. It is shown that increase the gas velocity would improve the gas holdupand liquid circulation rate, which means the more sufficiently gas and liquid weremixed, the better effect of flotation would be.This paper discusses the advantages and disadvantages of the existing flotationcolumns, and the theoretical basis for the MSSPFC. The structured packings, whichare widely used in separation process, are also used in this flotation column. Anotherpart of research work is finished in Qianjiaying Coal Slurry, Tangshan city, Hebeiprovince. Different gas-liquid flow ratio and residence time are chosen in theexperiment, then the sorting out samples are tested to get the ash percentage.In accordance with the structure of the MSSPFC, a plexiglass experimentaldevice is made. The author uses the PIV technology to observe and calculate thevelocity distribution in this device, in order to get a deeper research of the internalcirculating flowfield characteristics.After analysing and comparising the results of numerical simulation and coalslurry separation test, the author believe that the loop structure in this flotation columncan be further optimized, and the flotation system can be developed in the direction ofautomatization. In numerical simulation, a more comprehensive mathematical modelis necessary, in order to truly reflect the interaction between the phases in the flotation column. It is significant for improving the separation efficiency in the column and thescale-up of the column.