Journal of Sustainable Metallurgy ( IF 2.4 ) Pub Date : 2022-06-15 , DOI: 10.1007/s40831-022-00554-4 Yonglong Jin, Lihua Gao, Zhijun He, Yujia Sun
An economic and effective strategy synchronously utilizing blast furnace bag dust (BF-BD) and converter-removing dust (C-RD) by carbothermic reduction roasting is reported to achieve separation and recovery of iron and zinc. In this paper, the effect of operating parameters on the recovery rate and remove rate of Fe and Zn from BD and GD was initially studied by synergetic carbothermic roasting reduction. The optimized parameters include a reduction temperature pf 1200 °C, a reduction time of 90 min, a FC/O of 2.0, and a proportion of C-RD/BF-BD of 7:3, and the removal efficiency of Zn and metallization degree of Fe reached 98.35% and 90.58%, respectively. The phase transformation and stepwise reduction behavior of wüstite (ZnO)x(FeO)1−x, spinel ZnxFe1−xAl2O4, olivine ZnxFe2−xSiO4, and gehlenite ZnzFe2−xSiAl2O7 are systematically investigated by SEM–EDS, XRD, TG/DTG, and thermodynamic analyses. It was found that the formation of wüstite (ZnO)x(FeO)1−x as an intermediates plays an crucial role in the formation of metallic Zn–Fe–C alloy. Phase transformation and reduction mechanisms of C-RD and BF-BD and the interfacial reaction formation mechanism of wüstite (ZnO)x(FeO)1−x were discussed and clarified in synergistic carbothermic reduction process.
Graphical Abstract
中文翻译:
碳热还原-焙烧工艺协同利用含锌粉尘:相变与形态演化
报道了一种通过碳热还原焙烧同步利用高炉袋尘(BF-BD)和转炉除尘(C-RD)实现铁和锌分离回收的经济有效的策略。本文通过协同碳热焙烧还原法初步研究了操作参数对BD和GD中Fe和Zn回收率和去除率的影响。优化后的参数包括还原温度pf 1200 ℃、还原时间90 min、FC/O 2.0、C-RD/BF-BD 比例7:3、Zn和金属化去除率Fe含量分别达到98.35%和90.58%。维氏体 (ZnO) x (FeO) 1− x、尖晶石 Zn x的相变和逐步还原行为通过 SEM-EDS、XRD、TG/DTG 和热力学分析系统地研究了Fe 1- x Al 2 O 4、橄榄石 Zn x Fe 2- x SiO 4和钙长石 Zn z Fe 2- x SiAl 2 O 7 。发现作为中间体的维氏体 (ZnO) x (FeO) 1- x的形成在金属 Zn-Fe-C 合金的形成中起着至关重要的作用。C-RD和BF-BD的相变和还原机理与维氏体(ZnO) x (FeO) 1− x的界面反应形成机理在协同碳热还原过程中进行了讨论和澄清。