Dissolution Kinetics of Chlorine from Iron Ore Sintering Dust

Metals

Lihua Zhao¹  Haisheng Han²  Li Wang²  Wei Sun²  Honghu Tang²  Yue Yang² 

[1] Hunan Zhongye Changtian Energy Conservation and Environment Protection Technology Co., Ltd., Changsha 410205, China;School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China;

关键词: iron ore sintering dust;    dissolution kinetics;    Stumm’s kinetic model;    chlorine removing;    surfactant addition;   

DOI  :  10.3390/met11081185

来源: DOAJ

【 摘 要 】

Chlorine is generated during iron ore sintering, mostly in the form of alkali chlorides and primarily accumulates in sintering dust, which must be removed before reusing. In this study, an in-situ monitor leaching system based was designed to detect chloride ion water leaching behaviors in real-time and improve the understanding of chlorine dissolution kinetic behaviors in water. Various parameters, including water leaching temperature, solid/liquid ratio, stirring speed, particle size and surfactant addition have been studied. Meanwhile their chlorine dissolution data exhibited a good fit to Stumm’s kinetic models. The results of kinetics analysis and transition state theory calculation on apparent activation energy demonstrated that the dissolution process was controlled by diffusion at low S/L ratio, while changed to be controlled by surface chemical reaction as the S/L ratio increased. Furthermore, increasing both temperature and stirring speed improved the chlorine removal speed. Moreover, reducing the particle size and adding 0.2% nonionic surfactant Triton X-100 reduced the surface energy and accelerated surface chemical reaction, which were also beneficial for removing chlorine from sintering dust. In addition, the SEM-EDS examination inferred that the existence of laurionite (PbOHCl) limited the chlorine dissolution rate to less than 97%, while beneficiation or hydrometallurgy treatment was needed to further remove chlorine.

【 授权许可】

Unknown