The metallurgical properties of cold bound pellet were tested and analysed, and the behaviour and characters of reduction in the shaft were further investigated on the basis of analysis. The experimental results indic...The metallurgical properties of cold bound pellet were tested and analysed, and the behaviour and characters of reduction in the shaft were further investigated on the basis of analysis. The experimental results indicated that the metallurgical properties of cold bound pellet could satisfy the demands of the shaft direct reduction. The reduction of ferrous oxide with gas was taken as the domination. The reduction ratio of ferrous oxide with fixed carbon increased with the raising of temperature, and most part of the carbon remained in metallized pellet. The shaft could be smoothly operated to obtain rather higher constant utilization.展开更多
The influence of basicity on the metallurgical performances and reduction characteristics of fired super high-grade magnetite pellets under the simulated shaft furnace gas conditions was investigated.The fired pellets...The influence of basicity on the metallurgical performances and reduction characteristics of fired super high-grade magnetite pellets under the simulated shaft furnace gas conditions was investigated.The fired pellets in the basicity range of 0.09(natural basicity)to 1.00 show superior reducibility and low-temperature disintegration performance.However,in the basicity range of 0.20–0.80,the abnormal swelling of the fired pellets occurs.Improving basicity from 0.09 to 0.40 promotes the generation of low melting point slag phases and lower porosity of fired pellets,and accelerates the growth and densification of hematite crystals,impeding the reduction of hematite particles and the formation of metallic iron shell.In addition,the slags that distribute between the hematite particles absorb the reduction stresses by increased distances between the particles during the reduction process,which leads to the large reduction swelling of pellets.展开更多
文摘The metallurgical properties of cold bound pellet were tested and analysed, and the behaviour and characters of reduction in the shaft were further investigated on the basis of analysis. The experimental results indicated that the metallurgical properties of cold bound pellet could satisfy the demands of the shaft direct reduction. The reduction of ferrous oxide with gas was taken as the domination. The reduction ratio of ferrous oxide with fixed carbon increased with the raising of temperature, and most part of the carbon remained in metallized pellet. The shaft could be smoothly operated to obtain rather higher constant utilization.
基金The authors want to express their gratitude for the financial support from the National Natural Science Foundation of China(No.52004075)Science and Technology Planning Projects of Guizhou Province(No.ZK[2021]262)+1 种基金Program Foundation for Talents of Guizhou University(No.(2020)15)the Hunan Provincial Co-innovation Center for Clean and Efficient Utilization of Strategic Metal Mineral Resources.
文摘The influence of basicity on the metallurgical performances and reduction characteristics of fired super high-grade magnetite pellets under the simulated shaft furnace gas conditions was investigated.The fired pellets in the basicity range of 0.09(natural basicity)to 1.00 show superior reducibility and low-temperature disintegration performance.However,in the basicity range of 0.20–0.80,the abnormal swelling of the fired pellets occurs.Improving basicity from 0.09 to 0.40 promotes the generation of low melting point slag phases and lower porosity of fired pellets,and accelerates the growth and densification of hematite crystals,impeding the reduction of hematite particles and the formation of metallic iron shell.In addition,the slags that distribute between the hematite particles absorb the reduction stresses by increased distances between the particles during the reduction process,which leads to the large reduction swelling of pellets.
