Effect Of Circulation Capacity Change On Flow Field And Flotation Performance Of Wide-size-fraction Coal Flotator

As the coal preparation technology matures, it forms a pattern of coarse coal heavy media separation and small-sized coal flotation. And Coarse coal slime comes into focus. Because the equipment of heavy media develops in the direction of large-scale, the0.5-1mm coal cannot be separated effectively. At the same time,+0.3mm coal can not be recycled by flotation. Thus, the coal of1-0.3mm is to be separated effectively.The wide-size-fraction coal flotation machine has been designed by our research group after a lot of research and experiment. This flotation machine has extended the particle size of the flotation to1mm and solve successfully the problem of the coarse coal slime flotation. This paper researched the circulation volume of the wide-size-fraction coal flotation machine. Install the circuit baffle in the wide-size-fraction coal flotation machine in order to reduce the circulating volume in the high position. The effect of the circuit baffle on the flow field of the wide-size-fraction coal flotation machine was investigated by computational fluid dynamics soft on the water phase and the gas phase. The change of circulating volume and the impact of the flotation after install the circuit baffle in the wide-size-fraction coal flotation machine has been analyzed according to the numerical simulation results. It is very difficult to estimate the effect of flotation only by the change of a single factor. The laboratory flotation tests on the different wide-size-fraction coal flotation machine has been made. The experimental results showed that the flotation concentrates yield increased significantly. When the area of circuit baffle is37cm2of the circular channels, the flotation concentrates yield increased by9.98%. The growth of the yield of the coarse fraction is more. The flotation concentrates yield of the0.5-1mm increased by12.58%. At the same time, the tailings ash content of0.5-1mm increased by8.94%, the quantitative index of flotation concentrate and combustible mass recovery rate of0.125-1mm wide-size-fraction slime can reach up to81.04%and79.32%. It is proved that the flotation concentrates yield and the tailings ash content has increased significantly and the effect of flotation has improved after installing the circuit baffle in the wide-size-fraction coal flotation machine. Then, in order to recycle the coarse concentrates, make the flotation experiment again. According to the test results, flotation concentrates yield and the tailings ash content has increased by6.13%and6.25%, the yield of the0.5-1mm coarse coal slime has has increased by10.49%, the tailings ash content has increased by4.44%. The quantitative index of flotation concentrate and combustible mass recovery rate of0.125-1mm wide-size-fraction slime can reach up to88.99%and88.39%. Which show that the effect of flotation has improved further and has enhanced the impact of recycling of the coarse coal.