| 摘要 |
<p>PURPOSE:To reutilize dust contg. iron and caustic lime powder generated in an ironworks as materials for producing iron by treating them rationally depending on wet condition and chemical property of the dust at the collected stage. CONSTITUTION:Collected dust contg. iron and lime is classified to wet collected dust consisting primarily of fine powder and ore and lime powder consisting of coarse particle. The ore and lime powder are crushed in dry atmosphere with blown air to produce crushed product contg. >=65% particles having <=45mu particle size and <=5% water. On one hand, the wet collected dust is dehydrated to <=40% water content, or it is blended after dehydration with separately collected fine powder of low water content to adjust the water content of the blended product to <=40%. When it is further blended with above-described crushed caustic lime powder and spread on a drying floor, temp. is elevated by the heat of reaction and contained water is evaporated to reduce the water content to <=25%. The dried powder is blended with the above described crushed ore powder together with binder and kneaded to reduce the water content to <=10%, then granulated by rolling and utilized for the source of iron.</p> |
