| 摘要 |
<p>PROBLEM TO BE SOLVED: To produce a slag killing material for steelmaking which quickly breaks and degasses foamed slag. SOLUTION: (1) A series of processes of pulverization of one or more kinds of coal, etc., 1 and fine iron powder 1; addition of binder, mixture, heating, dehydration and melting is treated in one process with a high speed rotary mixer 5 having high speed stirring blades to execute compression formation and moisture adjustment. The (1) process is executed as the follows. The grain size of the fine iron powder is madeη1mm, and the ratio of coal, etc., to the fine iron powder is made (0-30):(100-70) in drying state by wt.% and at the time of using only the fine iron powder, thermaly-decomposable binder is used. Further, the fine iron powder consists of >=50wt.% metallic iron and uses converter OG dust, and the binder uses poval and/or PDA, etc. Then, the main raw material is indirectly heated to discharge the moisture outside the high speed rotary mixer, and the organic material is heated and melted with rotation friction heat. Water is added on the way of pulverizing the main raw material to adjust the moisture and a rust preventive, such as poly phosphoric acid, is added in the process (1).</p> |
