Patent ID: 7959008

Claim:
A method for screening first particles out of a granulate comprising first and second particles by conveying the granulate along a first screen surface, wherein the first particles have an aspect ratio a1, wherein a1≧n:1, with n=2, 3, >3, and the dimensions of the second particles allow them to fall through the mesh of the first screen surface, wherein the granulate is conveyed along the screen surface between said surface and a cover which extends along the screen surface, and the cover causes the first particles to be aligned with their longitudinal axes extending along the screen surface, wherein the longitudinal extension of each first particle is greater than the mesh width of the screen which forms the first screen surface, and the longitudinal extension of the second particles is equal to or smaller than the mesh width, wherein a sheet, which rests on the particles by virtue of gravitational force, or a plate is used as the cover, which is capable of pivoting around an axis which extends transversely to the direction of transport of the granulate on the first screen surface in such a way that a gap which extends between the first screen surface and the cover is adjusted based upon the size and/or shape of the particles, and wherein the particles are conveyed along the first screen by means of oscillation or vibration of the first screen.