| 摘要 |
<p>PURPOSE:To lower the melting point of steel making slag, improve fluidity and prevent the occurrence of any fault in the next process by adding SiO2, Fe2O3, etc. at the specific ratios into steel making slag. CONSTITUTION:The slag of the time when desulfurization with a CaO-base desulfurizer is performed at the steel making refining has much CaO content, is high in melting temperature and has poor fluidity; hence, it is likely to harden and becomes difficult to discharge in the next process, and these become the cause for various faults. In order to prevent this, SiO2-base ore, fly ash and iron oxide raw materials such as iron scraps and iron ore are charged to the slag in such a manner that the composition thereof becomes CaO<45%, SiO2<60%, FeO<10%. Beside these, a melting point lowering agent such as alkaline metals, compounds of alkaline earth metals, fluorides, alkali carbonate, or borate is added. These are blown together with a desulfurizer into the molten metal 3 in a ladle 2 through a lance 1, whereby the melting point of the slag 4 is lowered and this enables the fluidity to be made enhanced and the desulfurizing efficiency to be improved.</p> |
