| 摘要 |
<p>1,170,690. Reducing iron ore; HYDROCARBON RESEARCH Inc. Sept.19, 1967, No.42703/67. Heading C7D. Iron for powder metallurgical use is obtained by grinding an iron oxide e.g. hematite, magnetite or millscale to all pass a 20 mesh (Tyler) screen with not more than 25% passing 325 mesh, and reducing the ground ore in a fluidized bed at a temperature in the range 600‹ -1100‹ F and a pressure in the range 200-650 p. s. i. with a hydrogen-rich gas; the reduced iron is then ground without prior passivation to all pass 100 mesh and with 60 - 80% passing 325 mesh. The iron may then be sintered in the range 1600‹ - 2200‹F. and reground to size.</p> |
