1 School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, Hunan, China 2 National Engineering Research Center of Sintering and Pelletizing Equipment System, Zhongye Changtian International Engineering Co., Ltd., Changsha 410205, Hunan, China
Preparation of sinter with low reduction degradation index for COREX reduction in a high proportion
1 School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, Hunan, China 2 National Engineering Research Center of Sintering and Pelletizing Equipment System, Zhongye Changtian International Engineering Co., Ltd., Changsha 410205, Hunan, China
摘要 The sinter with low reduction degradation index (RDI) for COREX reduction was prepared by separated granulation sintering process. The results illustrate that the productivity and tumble index are attained to be 1.64 t m-2 h-1 and 59.25%, respectively, in pot tests under the optimal conditions. Under the reducing condition simulating COREX shaft furnace, RDI+6.3 mm, RDI+3.15 mm, and reducibility index of the sinter reach 63.05%, 81.52%, and 83.65%, respectively. Compared with traditional sintering process, the productivity rose by 14.69%, and RDI+6.3 mm and RDI+3.15 mm were increased by 157.54% and 32.70%, respectively. In addition, as the proportion of sinter reached 60%, RDI+6.3 mm and RDI+3.15 mm of comprehensive burden were achieved to be 73.39% and 84.28%, respectively, which could completely meet the requirement of COREX shaft furnace for RDI. The mechanism was demonstrated that the more silicoferrites of calcium and aluminum and silicate phase occurred as well as magnetite, and the amount of Fe2O3 decreased substantially in the sinter by separated granulation sintering process. Hence, the low-temperature reducing stress is restrained, with the increase in sinter strength.
Abstract：The sinter with low reduction degradation index (RDI) for COREX reduction was prepared by separated granulation sintering process. The results illustrate that the productivity and tumble index are attained to be 1.64 t m-2 h-1 and 59.25%, respectively, in pot tests under the optimal conditions. Under the reducing condition simulating COREX shaft furnace, RDI+6.3 mm, RDI+3.15 mm, and reducibility index of the sinter reach 63.05%, 81.52%, and 83.65%, respectively. Compared with traditional sintering process, the productivity rose by 14.69%, and RDI+6.3 mm and RDI+3.15 mm were increased by 157.54% and 32.70%, respectively. In addition, as the proportion of sinter reached 60%, RDI+6.3 mm and RDI+3.15 mm of comprehensive burden were achieved to be 73.39% and 84.28%, respectively, which could completely meet the requirement of COREX shaft furnace for RDI. The mechanism was demonstrated that the more silicoferrites of calcium and aluminum and silicate phase occurred as well as magnetite, and the amount of Fe2O3 decreased substantially in the sinter by separated granulation sintering process. Hence, the low-temperature reducing stress is restrained, with the increase in sinter strength.
Sheng-hu Lu,Jian Pan,Si-wei Li, et al. Preparation of sinter with low reduction degradation index for COREX reduction in a high proportion[J]. Journal of Iron and Steel Research International, 2023, 30(4): 635-649.
2023, Vol. 30 
