氧化铁含量对煤渣冷却结晶特性的影响

Influence of Fe_2O_3 Content on Crystallization Behavior of Slag at Cooling Process

以神府烟煤为原料制备煤渣,并在渣中添加氧化铁,研究氧化铁含量对煤渣冷却结晶特性的影响。采用高温热台显微镜(HTSM)观察不同降温速率下晶体的析出过程,使用扫描电子显微镜(SEM)和能谱(EDS)分析晶体微观形态以及元素组成,运用X射线衍射仪(XRD)检测晶相,并用热力学模拟软件Factsage模拟高温下煤渣的平衡相图。结果表明,惰性气氛下渣中氧化铁质量分数的增加会促进晶体的析出,减少晶体培育时间,提高晶体初始析出温度并增大晶体尺寸;当氧化铁质量分数达到30%时,析出晶体的Fe元素含量增加,析出晶体由钙高铁辉石晶体转变为磁铁矿晶体。

Effect of Fe2O 3 content on the melting crystallization properties of slag was explored using Shenfu coal as raw material and Fe2O 3 as additive. High-temperature stage microscopy （H T SM ） was applied to observe the crystallization process under different cooling rate. Scanning electron microscopy （SEM） and energy-dispersive spectrometry （EDS） detected the microstructures and element compositions of the crystal. X-ray diffraction （XRD） was used to determine the crystalline phases,and Factsage was used to simulate the slag equilibrium phase diagram at high temperature. As the iron oxide mass fraction increased under inert atmosphere, precipitation of crystal was promoted, the incubation time of crystals reduced, the initial precipitation temperature of crystals increased, and the size of crystals enlarged. Whenthe Fe2O 3 mass fraction reached 30% %he content of iron in crystals was increased and the crystalline phase was changed from calcium iron pyroxene to magnetite crystal.