| 摘要 |
PROBLEM TO BE SOLVED: To provide a technology for efficiently and accurately classifying particles of 50 μm or less with a simple device.SOLUTION: In a classifying container 10, a jet part is formed with gas supply from a jetted gas supply port 12 and a circulation part is formed on a side surface of the classifying container 10. In addition, the circulation part is assisted by gas supply from a jetted assistant gas supply port 15. Thereby, a jet layer is efficiently formed. A jetted gas supply device 20 and a jetted assistant gas supply device 50 are controlled so that the flow speed of the jet is equal to ot more than a last speed of particles having a border particle diameter. As a result, particles having a particle diameter equal to or less than the border particle diameter rise together with the jet part of the jet and recovered in a fine powder recovery device 40 from a fine powder recovery port 14. On the other hand, particles having a particle diameter larger than the border particle diameter go down together with the circulation part of the jet and are recovered in a coarse powder recovery device 30 from a coarse powder recovery port 13. |
