| 摘要 |
1453851 Ball mills; comminuting at low temperatures BOC INTERNATIONAL Ltd 10 July 1974 [18 July 1973] 34114/73 Heading B2A Wire scrap is comminuted in a ball mill 21 with liquid nitrogen, the powdered insulation being blown through and separated in a cyclone 49, and the stripped wire being discharged from the mill at 59 through perforations 45 into a hopper 61. Chopped wire lengths are fed in at 37 and cooled before or after they reach the mill and as shown by sprinklers 43. Hollow balls 35 may be used to reduce cold absorption and may be of different sizes, reducing from left to right, Fig. 2. A fan 53 maintains a recirculating cold gas flow. The mill 21 and conduits 47, 51, 39 are thermally jacketted. |
