For -100mesh silica sand, downstream feeding method is adopted(7 is feeding inlet,5 for outlet). Slurry magnetic separator adopts intermittent working method. When slurry is fed,4# valve close, then slurry comes through 7# valve to enter into working chamber, coils in working chamber will generate strong magnetic force to attracted the paramagnetic particles to magnetic medium(2),non-magnetic matter will go through 5# valve and then lead to concentration pond. After running for a period,5# valve will close,7# inlet valve close and 4# valve opens, and turn off the power of coils(no magnetic field this time),then open run motor of vibrator,flushing pump, under the action of 8# vibrator and 1# flushing water, paramagnetic particles will be discharged from 4# valve, after this has been done,7# valves is open,4# valve closes,5# is open, and a circulating circle is done.   Coil Coils of made of copper with pureness above99.95%, no usage of aluminum or other alloy substance has been used. Copper coils is purchased and checked as per National Standard GB/T1527-2006, GB/T 20301-2006.conductivity of coil is 10% higher than general ones. Coils are dipped into transformer oil, to decrease the temperature of coils quickly and steadily, circulating device is equipped with external heat exchanger.it guarantees that the outlet cooling water of coils is less than 62 Celsius degrees, thus magnetic field fluctuation is under reasonable control range.      Magnetic medium: magnetic medium is made of special iron substance, after special treatment, permeability has been enforced, after power off of coils, there is no remanence. Density of magnetic medium is winded according to the product mesh of user, when slurry goes through magnetic medium (Fig 1, right), paramagnetic particles have been attracted to it, and then the beneficiation has been improved.