钢渣超微粉理化特性

超微粉化是实现钢渣高效利用的重要途径,但不同粒度的钢渣超微粉的理化性质不同。利用激光粒度分析仪、X射线荧光光谱仪、X射线衍射仪和热失重分析仪,分别测定不同粒度钢渣超微粉的粒度分布、化学元素组成、矿物组成和热失重。结果表明:钢渣超微粉的D50(D50为粒度分布曲线中数量累积分布为50%的等效直径)在3.15~15.78μm之间。随着D50的增加,样品中Ca的质量分数递减,减少量达18.60%,Fe、Mn、V、P的质量分数递增,增加量分别达104.58%、154.90%、129.03%和163.64%;Si、Mg、Al和Ti的含量随超微粉粒度变化规律不明显。随Fe含量的增加,钢渣超微粉的松装密度增大。随样品粒度的增大,Ca(OH)_2和CaCO_3衍射峰逐渐变弱直至消失,RO相和Ca_2Fe_2O_5的衍射峰逐渐增强,硅酸二钙(C2S)和硅酸三钙(C3S)衍射峰变化不明显。随着样品粒度减小,可热分解的钙镁化合物MgCO_3、Ca(OH)_2和CaCO_3含量逐渐增加。

Physicochemical properties of steel slag ultra-fine powder

Ultra-fine powdered process is an important way to achieve efficient utilization of steel slag.The physical and chemical properties of ultra-fine powder (UPF) of steel slag with different particle sizes are different.The particle size distribution,chemical composition,phase composition and thermogravimetric characteristics were respectively analyzed by laser particle size analyzer (LSA),X-ray fluorescence spectrometer (XRF),X-ray diffraction (XRD) and therrnogravimetric analyzer (TGA).The results show that Ds0,which presents equivalent diameter meaning the number of particles is accumulated to 50％ according to size distribution curves,ranges from 3.15 μtm to 15.78μm.With increasing the particle size,the mass fraction of Ca in the sample decreases by maximum reduction of 18.60mass ％ and Fe,Mn,V and P contents increase by the maximum increments of 104.58 mass ％,154.90 mass ％,129.03 mass ％ and 163.64 mass ％,respectively;there is no obvious relationship of Si,Mg,Ti and Al contents to particle size.With increasing the Fe content,apparent density of steel slag UFP increases.With increasing particle size,the diffraction intensity of Ca(OH)2 and CaCO3 by XRD plot weaken gradually and disappear finally,the diffraction intensity of RO phase minerals and Ca2Fe2O5 enhance gradually,and the diffraction peak intensity of dicalcium silicate (C2S) and tricalcium silicate (C3S) change not conspicuously.With decreasing the particle size,the contents of the decomposable calcium and magnesium compounds (Mg-CO3,Ca(OH)2 and CaCO3) increase.