摘要 |
A sieving apparatus includes first and second sieving portions. The first sieving portion includes a sieve with a plurality of elongated holes or slits for separation of an object to be sieved based on difference in cross-sectional diameter. The second sieving portion with a sieve constituted by a porous plate includes round holes for separation of the object that has passed through the elongated holes or slits based on difference in aspect ratio. The second sieving portion is employed after sieving by the first sieving portion. A diameter of the round holes in the porous plate constituting the sieve included in the second sieving portion is longer than an opening width in a shorter direction of the elongated hole or the slit of the sieve included in the first sieving portion. |