不同种类转炉钢渣对高铁分相熟料烧成与性能的影响

Effect of Different Types of Converter Steel Slag on Sintering and Properties of High-Ferrite Multi-Phased Clinker

钢渣分相熟料是直接利用粒状钢渣煅烧的水泥熟料,因此钢渣自身的物理化学特性对分相熟料的烧成至关重要。为探究不同种类转炉钢渣对分相熟料烧成与性能的影响机制,采用热焖渣、滚筒渣和有压热焖渣在1420℃制备了3种钢渣分相熟料。结果表明:不同种类转炉钢渣分相熟料矿物以C_(3)S、C_(2)S和C_(4)AF为主,钢渣中的铁质成分含量高,使分相熟料中的Al基本转化为铁铝酸盐矿物(Ferrite),呈现典型的高铁(Ferrite含量>18%,质量分数)特征。不同种类转炉钢渣间化学成分、矿物组成及粒径分布的差异,对分相熟料矿物晶体的形成发育和性能产生了不同的影响。分相熟料中水溶性铬(VI)含量与钢渣中的Cr2O3和碱含量呈正相关,且钢渣中的细颗粒含量越高,Cr越容易在烧成过程中被氧化成水溶性高价铬酸盐。

Steel slag multi-phased clinker is a cement clinker directly calcined by granular steel slag,so the physical and chemical characteristics of steel slag are very important to the sintering of multi-phased clinker.In order to explore the influence mechanism of different types of converter steel slag on the sintering and properties of multi-phased clinker,three kinds of multi-phased clinker were prepared by using hot smoldering slag,roller slag and pressurized hot smoldering slag at 1420℃.The results show that the multi-phased clinker minerals with different steel slag were mainly C_(3)S,C_(2)S and C_(4)AF,the higher iron content in steel slag resulted in the Al transformed into ferrite minerals,showing a typical high ferrite(Ferrite content>18%,mass fraction)characteristic.The differences of chemical composition,mineral composition and particle size distribution among different steel slag had different influences on the formation and development of mineral crystals and properties of multi-phased clinker.The content of water-soluble chromium(VI)in multi-phased clinker was positively correlated with the content of Cr2O3 and alkali in steel slag,and the higher the content of fine particles in steel slag,the more easily Cr was oxidized into water-soluble high valence chromate in the sintering process.