为了研究同轴旋转磁场对重介质旋流器分选效果的影响，将永磁铁分别同轴置于距离筒锥 交界面 80，120 和 160 mm 处，采用三相异步电机来控制永磁铁的旋转速度及方向，在无磁场、静态 磁场、永磁铁旋转方向与矿浆入料方向一致、永磁铁旋转方向与矿浆入料方向相反的 4 种状态下进 行-3 mm 粗煤泥分选试验。 选取了距离筒锥交界面 120 mm 处的无磁场、静态磁场、永磁铁旋转方 向与矿浆入料方向一致且转速为 851 r/ min、永磁铁旋转方向与矿浆入料方向相反且转速为 421 r / min的 4 个试验点进行重选效果评定试验，并利用 ANSYSMAXWELL 分析软件对静态磁场进 行模拟分析。 由分选试验结果可知:静态磁场时的各粒级精煤与尾煤灰分均低于无磁场时的精煤 与尾煤灰分;永磁铁旋转方向与矿浆入料方向一致时的各粒级精煤与尾煤灰分均高于静态磁场时 的精煤与尾煤灰分;永磁铁旋转方向与矿浆入料方向相反时的各粒级精煤灰分均低于静态磁场时 的精煤灰分或基本持平，尾煤灰分均高于静态磁场时的尾煤灰分或基本持平。 由重选效果评定结果可知:δpNon-magnetic>δp(+851) >δp(-421) >δpMagnetostatic;EpNon-magnetic>EpMagnetostatic≈Ep(+851) >Ep(-421)。 静态磁场 时的分选密度比无磁场时降低了 0.090 g / cm3 ，但分选精度有所提高;永磁铁旋转时的分选密度介 于无磁场与静态磁场间，分选精度高于或等于无磁场与静态磁场时，旋转方向一致且转速为 851 r / min 时的分选密度要高于旋转方向相反且转速为 421 r / min 时的分选密度，但分选精度要低于旋 转方向相反且转速为 421 r / min 时的分选精度。 对所在的永磁场进行模拟分析，初步揭示了置于 锥部的永磁体可以降低重介质旋流器分选密度的原因是:斜向下的磁力将更多的磁铁矿粉吸引到 底流口，并从底流口排除，从而降低了重介质旋流器的分选密度。 永磁铁旋转方向与矿浆入料方向 相反时对旋流器内部的磁铁矿粉有加速作用，有助于提高分选精度。

In order to study the influence of the coaxial rotating magnetic field on the separation effect of the dense me⁃ dium cyclone，the permanent magnets are placed coaxially at 80，120 and 160 mm from the interface of the cone and cone，and a three⁃phase asynchronous motor is used to control the rotation speed of the permanent magnet. And the direction，the -3mm coarse slime separation test is carried out under four conditions: no magnetic field，static magnetic field，the rotation direction of the permanent magnet is consistent with the direction of slurry feeding， and the rotation direction of the permanent magnet is opposite to the direction of slurry feeding. Select the non-mag⁃ netic field，static magnetic field at a distance of 120 mm from the barrel⁃cone interface，the rotation direction of the permanent magnet is consistent with the slurry feeding direction and the speed is 851 r / min，the permanent magnet ro⁃ tation direction is opposite to the slurry feeding direction，and the speed is 421 r / min four test points for reselection effect evaluation test，and use ANSYSMAXWELL analysis software to simulate and analyze the static magnetic field. From the results of the separation test，it can be seen that the ash content of the clean coal and tailings in the stat⁃ ic magnetic field is lower than the ash content of the clean coal and tailings in the non⁃magnetic field; the rotation di⁃ rection of the permanent magnet is consistent with the direction of the slurry feeding. The ash content of coal and tail⁃ ings is higher than the ash content of clean coal and tailings under a static magnetic field; when the rotating direction of the permanent magnet is opposite to the direction of slurry feeding， the ash content of each particle size of the cleaned coal is lower than the ash content of the cleaned coal under the static magnetic field or is basically the same ，The ash content of the tail coal is higher than the ash content of the tail coal under the static magnetic field or basically the same.From the evaluation results of the reselection effect，we can see:δp Non-magnetic >δp(+851) >δp(-421) > δp Magnetostatic; Ep Non-magnetic > Ep Magnetostatic ≈ Ep(+851) > Ep(-421) . The separation density under static magnetic field is 0.090 g / cm3 lower than the separation density under no magnetic field，but the separation accuracy is improved; the separation density when the permanent magnet rotates is between no magnetic field and static magnetic field. The ac⁃ curacy is higher than or equal to the separation accuracy when there is no magnetic field and static magnetic field. The separation density when the rotation direction is the same and the rotation speed is 851 r / min is higher than that when the rotation direction is opposite and the rotation speed is 421 r / min. The separation density，but the separation accuracy is lower than the separation accuracy when the rotation direction is opposite and the speed is 421 r / min.The simulation analysis of the permanent magnetic field reveals that the permanent magnet placed in the cone can re⁃ duce the separation density of the dense medium cyclone. The reason is that the oblique downward magnetic force at⁃ tracts more magnetite powder to the bottom orifice.，And removed from the underflow port，thereby reducing the density of the dense medium cyclone separation. When the separation direction of the permanent magnet is opposite to the feeding direction of the slurry，it will accelerate the magnetite powder inside the cyclone and help improve the separa⁃ tion accuracy.