To efficiently separate and recover a dirt component by precipitating and separating the dirt component by a physical method even when a heavy material such as a metal compound is included in waste liquid as the dirt component.

An apparatus for clarifying waste liquid includes: a flocculant injection device 10 for injecting ferrite powder into the waste liquid as a flocculant; a flocculation reaction device 20 for stirring the waste liquid with which the ferrite powder is mixed by applying a rotary magnetic field to the waste liquid; and a precipitation tank 30 where the waste liquid from the flocculation reaction device is injected and clarified liquid can be taken out from its upper part after precipitating the ferrite powder. Since the dirt component in the waste liquid is stuck onto a ferrite powder surface and is precipitated in the precipitation tank, a clarification function can be accomplished even when the metal compound is included in the dirt component.