Method and apparatus for separation of mixture

Abstract

The present invention provides a method and an apparatus for separating a mixture that are capable of separating a mixture containing a plurality types of particles, using a countercurrent classification technique, even when there is little difference in density and particle diameter depending on the types of particles. In the present invention, a mixture containing first particles and second particles is separated using a separation tubehaving the inverted-conical or pyramidal shape or a substantially inverted-conical or pyramidal shape. The first particles and the second particles are made of substances having different magnetic susceptibilities. A fluid is caused to flow upward through the separation tube, and the flow of the fluid is used to introduce the mixture into the separation tube. The first particles and the second particles are held in the separation tubein a mixed state. A gradient magnetic field is applied to a region inside the separation tubeusing magnetic field generation means, in the state where the first particles and the second particles are held in the separation tube. The magnetic field gradient of the gradient magnetic field has a vertical component.