Effects and mechanisms of fluorite on the co-reduction of blast furnace dust and seaside titanomagnetite
来源期刊：International Journal of Minerals Metallurgy and Materials2017年第11期
论文作者：Tian-yang Hu Ti-chang Sun Jue Kou Chao Geng Yong-qiang Zhao
文章页码：1201 - 1210
摘 要：The co-reduction roasting and grinding-magnetic separation of seaside titanomagnetite and blast furnace dust was investigated with and without fluorite addition at a reduction roasting temperature of 1250°C for 60 min, a grinding fineness of-43 μm accounting for 69.02 wt% of the total, and a low-intensity magnetic field strength of 151 kA/m. The mineral composition, microstructure, and state of the roasted products were analyzed, and the concentrations of CO and CO2 were analyzed in the co-reduction roasting. Better results were achieved with a small fluorite dosage（≤4 wt%） in the process of co-reduction. In addition, F- was found to reduce the melting point and viscosity of the slag phase because of the high content of aluminate and silicate minerals in the blast furnace dust. The low moisture content of the blast furnace dust and calcic minerals inhibited the hydrolysis of CaF2 and the loss of F-. Compared with the blast furnace dust from Chengdeng, the blast furnace dusts from Jiugang and Jinxin inhibited the diffusion of F-when used as reducing agents, leading to weaker effects of fluorite.
Tian-yang Hu1,2，Ti-chang Sun1,2，Jue Kou1,2，Chao Geng1,2，Yong-qiang Zhao1,2
1. School of Civil and Resources Engineering, University of Science and Technology Beijing2. Key Laboratory of Ministry of Education of China for Efficient Mining and Safety of Metal Mines
摘 要：The co-reduction roasting and grinding-magnetic separation of seaside titanomagnetite and blast furnace dust was investigated with and without fluorite addition at a reduction roasting temperature of 1250°C for 60 min, a grinding fineness of-43 μm accounting for 69.02 wt% of the total, and a low-intensity magnetic field strength of 151 kA/m. The mineral composition, microstructure, and state of the roasted products were analyzed, and the concentrations of CO and CO2 were analyzed in the co-reduction roasting. Better results were achieved with a small fluorite dosage（≤4 wt%） in the process of co-reduction. In addition, F- was found to reduce the melting point and viscosity of the slag phase because of the high content of aluminate and silicate minerals in the blast furnace dust. The low moisture content of the blast furnace dust and calcic minerals inhibited the hydrolysis of CaF2 and the loss of F-. Compared with the blast furnace dust from Chengdeng, the blast furnace dusts from Jiugang and Jinxin inhibited the diffusion of F-when used as reducing agents, leading to weaker effects of fluorite.
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