Experimental study on mechanism of direct reduction of metallurgical dust carboncontaining pellets
HE Huanyu, LIU Hongling, CUI Yifang, LI Yang, DING Juan
1.The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology,Wuhan 430081, Hubei, China;2.Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081, Hubei, China;3.Hubei Provincial Engineering Technology Research Center of Metallurgical Secondary Resources,Wuhan 430081, Hubei, China
Abstract:Abstract: Based on gassolid reaction kinetics model, direct reduction process of metallurgical dust carboncontaining pellets were studied. The characteristic parameters of reduction rate, reduction degree and reduction atmosphere that characterize the reduction characteristics were investigated systematically. The results show the reduction behavior and mechanism of metallurgical dust carboncontaining pellets in the reaction process were illustrated clearly. Reduction process of metallurgical dust carboncontaining pellets can be divided into three steps: startup stage, rapid response and the response end period. The reaction process is fast, and the temperature for carbon gasification and iron oxide reduction can be reached in 3-5minutes. Under 1270℃, the reduction content of the carboncontaining pellets is increased with the increasing of temperature. However, with the further increase of temperature, n(C)/n(O) and the consumption of carbon in pellets have a more significant impact on the reduction process, which is reflected in the prolonged maintenance time of the maximum reduction rate and the greatly increased reduction degree. Carbon gasification is the most important part of the reduction process of carbon containing pellets, because the produced CO determines the reduction rate of pellets. The reaction process is in an obvious reducing atmosphere. The CO2 in the atmosphere comes from the further oxidation of part of CO, and its content depends on the amount of CO in the atmosphere and the progress of the reaction.
何环宇1,2,3,刘虹灵1,2,3,崔一芳1,2,3,李杨1,2,3,丁娟1,2,3. 冶金尘泥含碳球团直接还原机制的试验研究[J]. 钢铁研究学报, 2021, 33(3): 196-201.
HE Huanyu1,2,3, LIU Hongling1,2,3, CUI Yifang1,2,3, LI Yang1,2,3, DING Juan1,2,3. Experimental study on mechanism of direct reduction of metallurgical dust carboncontaining pellets. JOURNAL OF IRON AND STEEL RESEARCH , 2021, 33(3): 196-201.