| 摘要 |
<p>PURPOSE:To effectively utilize converter slag which is generated in a large amt. in iron and steel making industry and the effective utilization for which is not yet established. CONSTITUTION:The converter slag is slowly cooled by spending 1 to 3 hours between 400 deg.C and 900 deg.C in the process of subjecting the slag to a heating treatment for 15 to 180 minutes or cooling the slag from a molten state, by which the free lime content (measured by a Frank method) contained in the converter slag to <=1% and, therefore, the converter slag is usable as the admixture for cement concrete. The converter slag heat treated in such a manner has an effect of suppressing the carbonization speed of the cement concrete to 50% of the ordinary speed and has further an effect of taking in Cl<->, SO4<--> as a salt injury resistance effect. Further, the long-term compressive strength is improved by the effect of beta-C2S incorporated into the converter slag and simultaneously, the converter slag is helpful as the admixture of a low exothermic type and eventually, the converter slag is effectively utilized as the blank material to improve the durability of the concrete.</p> |
