Reaction characteristics of steelmaking slag carbonation in dilute alkali medium
WANG Chen-ye1,2，BAO Wei-jun2，XU De-hua2，GUO Zhan-cheng1，LI Hui-quan2，PAN Kai2
（1. State Key Laboratory of Advanced Metallurgy，University of Science and Technology，Beijing 100083，China 2. Key Laboratory of Green Process and Engineering，National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology，Institute of Process Engineering，CAS，Beijing 100190，China）
Abstract：Steelmaking slag carbonation mineralization is an effective method for CO2 in-situ fixation. The rate of steelmaking slag carbonation process could be enhanced by adding alkali medium with low concentration. The influences of processing conditions，such as stirring speed，reaction temperature and dilute alkali concentration，on carbonation efficiency were systematically studied. The optimal carbonation conditions are： stirring speed of 450 r/min，temperature of 70 ℃，dilute alkali concentration of 20 g/L. Under optimal conditions，the carbonation efficiency is approximately 49.72%，almost 1.8 times as high as traditional water system. At the same time，the reaction condition is mild，the dilute alkali can be recycled in this process. Reaction kinetics model of the steelmaking slag carbonation was established. The results show that the steelmaking slag carbonation reaction was controlled by internal diffusion，and the calculated apparent activation energy is 22.48 kJ/mol.
2016, Vol. 51 
