滚筒渣与热闷渣基础性能研究

Study on basic performance of roller steel slag and hot smoldering steel slag

摘要:

为实现钢渣的高效资源化利用,采用X射线荧光光谱（XRF）、X射线衍射（XRD）、扫描电镜（SEM）、粒径分布、安定性、易磨性等检测方法研究了滚筒法、热闷法处理工艺对钢渣基础性能的影响. 研究表明:滚筒渣和热闷渣的主要化学成分和物相组成相差不大,滚筒渣中硅酸二钙(C₂S)、硅酸三钙(C₃S)和铁酸二钙(C₂F)的质量分数较大,且可以较明显的观察到金属铁粒; 与热闷渣相比,滚筒渣中CaO质量分数较大,而 f-CaO质量分数较少.在2.0 MPa饱和蒸汽下进行压蒸试验发现,在相同粒径范围内,滚筒渣的安定性指数普遍大于热闷渣,安定性优异. 采用水泥试验小磨进行粉磨,得到比表面积随粉磨时间延长的特征曲线. 结果发现,在相同的粉磨时间内,滚筒渣的比表面积均小于热闷渣的比表面积,当粉磨时间超过70 min时,滚筒渣的粉磨效率趋于平缓,而热闷渣继续粉磨到110 min时,比表面积增加15.67%,因此滚筒渣的易磨性较差.粒度筛分与压碎值测定试验结果显示,滚筒渣的粒径大部分集中在3~5 mm,热闷渣主要集中在3~10 mm且粒度分布较均匀; 滚筒渣和热闷渣粗细骨料的压碎值均达到Ⅰ类粗细骨料技术指标,可直接用作粗细骨料.

Abstract:

To achieve efficient resource recovery of steel slag, the effects of roller method and hot smoldering process on the basic properties of steel slag were studied by means of X-ray fluorescence spectrometry (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM), particle size distribution, stability, and grindability. Research indicates that the main chemical composition and phase composition of roller steel slag (RSS) and hot smoldering steel slag (HSSS) have little difference. RSS contains a large amount of dicalcium silicate (C₂S), tricalcium silicate (C₃S), and dicalcium ferrite (C₂F), and metal iron particles can be observed clearly. Compared with HSSS, the CaO content of RSS is larger, while the f-CaO content is smaller. Autoclave stability test was carried out under 2.0 MPa saturated steam, and it was found that with in the same particle size range, the stability index of RSS was higher than that of HSSS, indicating that RSS has better stability. Cement test mill was used for grinding, and the curve of specific surface area with the increase of grinding time was obtained. Results show that during the same grinding time, the specific surface area of RSS was smaller than that of HSSS. When the grinding time exceeded 70 min, the grinding efficiency of RSS tended to be gentle, while the specific surface area of HSSS increased by 15.67% when the grinding time reached 110 min, which suggests that RSS has poor grindability. Sizing experiments and crush value test show that the particle size of RSS was mostly 3-5 mm, while that of HSSS was mainly 3-10 mm, and the particle size distribution was relatively uniform. The crushing values of RSS and HSSS coarse and fine aggregates both reached the technical index of type I coarse and fine aggregates, which can thus be directly used as coarse and fine aggregates.