It is a kind of electro-magnetic preperation equipment suitable for sorting fine-grained and weak magnetic ore. The magnetic preparation with pulsating and high gradient can increase in large amounts the grade of magnetic fine ore and the ore-dressing efficiency. The vertical ring is utilized to transport the magnetic medium, and to flush a magnetic fine ore by reversing the magnetic polarity. The vertical ring combined with pulsation might effectively prevent the magnetic medium from block and increase the upper limit of sorting grain. The pulsating stroke, times of stroke, intensity of magnetic field, flow rate of pulp and rotating speed of rotary ring, ect, can be adjusted in rather large range. By using of this invention to sort fine-grain, weak magnetic ore with the grain less than 1 mm, a fine quota of magnetic dressing can be obtained. |