Microstructure Variation of Pellets Containing Ferrous Dust during Carbonation Consolidation

作     者：Yan SHI Shi-meng LIU Chang-qing HU Yu-zhu ZHANG 

作者机构：College of Material and MetallurgyNortheastern University Hebei Key Laboratory of Modern Metallurgy TechnologyHebei United University 

出 版 物：《Journal of Iron and Steel Research International》 (Journal of Iron and Steel Research, International)

年 卷 期：2015年第22卷第2期

页      面：128-134页

核心收录：

学科分类：0806[工学-冶金工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080601[工学-冶金物理化学] 0703[理学-化学] 0801[工学-力学（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：Sponsored by National Natural Science Foundation of China(51074061) Natural Science Foundation of Hebei Province of China(E2011209039) 

主　　题：ferrous dust microstructure CaO conversion rate carbonated pellet green pellet 

摘      要：The carbonation and microstructure characteristics of pellets containing ferrous dusts were investigated during carbonation consolidation at differem reaction temperatures and CO2 partial pressures. The results indicated that green pellets had loose and network supporting structure with initial strength, and large cracks and pores existed in the pellets. The carbonation reaction was controlled by interracial chemical reaction at the initial fast stage, which limited diffusion and thus caused the reaction rate to decrease. With increasing reaction temperature and CO2 partial pressure, the conversion rates of CaO and the number of microcrystalline CaCO3 particles increased, and the volume expansion of CaCO3 led to a decrease in the open porosity, average pore size and specific surface area of the pellets. Micro pores were occluded, and the number of smaller pores （diameter less than 50 nm） increased, thereby resulting in the more compact and uniform structure of carbonated pellets. Simuhaneously, the dense structure prevented CO2 diffusion into the product layer, affecting the increase in carbonation conversion rate.