PURPOSE: To separate and recover a magnetic component and a non-magnetic component in high purity and good efficiency, by a method wherein raw water containing the magnetic component and the non-magnetic component is recirculated to be introduced into a magnetic filter and, after a magnetic field is demagnetized,washing water is passed therethrough.

CONSTITUTION: Raw water A having a magnetic component and a non-magnetic component mixed therein is introduced into a magnetic filter 1 having a magnetic field formed thereto through a recirculation pit 10 and the magnetic component is collected by filter media 5 in such a state that the part of the non-magnetic component is entrapped therein. The filtered matrix liquid is returned to the recirculation pit 10 to be again passed through the magnetic filter 1. The non-magnetic component entrapped in the magnetic component is released and discharged in a state accompanied by the filtered matrix liquid. When the amount of the recirculation liquid reaches 1, 2 times or more with respect to the amount of raw water, the recirculation is stopped and the supply of a current to the magnetic field is cut off. In the next step, washing water B is passed through the magnetic filter 1 to wash off the magnetic component collected by the filter media 5 and washing water containing the magnetic component at high concn. is transferred to a magnetic component-containing slurry storage pit 18.