摘要
为降低铁矿球团干燥过程的生产成本,加快成球速度,促进大球团形成,提升球团的综合性能,本文以10~12、12~14、14~16 mm和16~18 mm这四种粒度范围的球团为研究对象,探索粒度大小对球团性能及工艺条件的影响。结果表明:增大球团粒度需要更高的造球水分和更长的造球时间,并且生球的落下强度和抗压强度显著提升;随着球团粒度的增大,预热球内部颗粒的排列更加规整,成品球内部的固相占比增加,气孔减小,晶体连接更好,致密性提高,预热球和成品球的抗压强度均增大;球团粒度不宜高于16 mm,当粒度提高至16~18 mm时,还原膨胀指数由11.6%降低至9.7%,还原度指数由70.7%降低至54.5%,还原度变差;铁精矿的轻度干燥或免干燥有助于提高球团粒度,大幅降低生球中<12 mm粒级的占比,提升12~16 mm粒级占比,使生球的粒度分布更均匀。因此,在球团生产中将粒度控制在12~16 mm,既能节省干燥成本,又能获得更好的球团性能指标,为后续高炉冶炼提供更多优质炉料。
In order to reduce the production cost of iron ore pellets drying process,accelerate the pelletization speed,promote the formation of large pellets,and improve the comprehensive performance of pellets,the pellets in the range of 10~12,12~14,14~16 mm and 16~18 mm are taken as the research objects to explore the influence of particle size on pellets performance and process conditions.The results show that increasing the particle size of the pellets requires higher pelletizing moisture and longer pelletizing time,and the falling strength and compressive strength of the fresh pellets are significantly improved.With the increase of pellets size,the arrangement of particles inside the preheating pellets is more regular,the proportion of solid phase inside the finished pellets increases,the porosity decreases,the crystal connection is better,the compactness is improved,and the compressive strength of the preheating pellets and the finished pellets increases.The particle size of pellets should not be higher than 16 mm,when the particle size is increased to 16~18 mm,the reduction expansion index decreases from 11.6%to 9.7%,and the reduction index decreases from 70.7%to 54.5%,and the reduction degree becomes worse.Mild drying or non-drying of iron ore concentrate can help to improve the particle size of pellets,greatly reduce the proportion of<12 mm particle size in fresh pellets,increase the proportion of 12~16 mm particle size,and make the particle size distribution of green pellets more uniform.Therefore,controlling the particle size at 12~16 mm in pellets production can not only save drying costs,but also obtain better pellets performance indexes,and provide more high-quality charges for subsequent blast furnace smelting.
作者
韩涛
杨大兵
王炜
黄渝茜
HAN Tao;YANG Dabing;WANG Wei;HUANG Yuqian(Wuhan University of Science and TechnologySchool of Resources and Environmental Engineering,Wuhan 430081,Hubei,China;Wuhan University of Science and TechnologyHubei Province Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources,Wuhan 430081,Hubei,China;Wuhan University of Science and TechnologyInstitute of Materials and Metallurgy,Wuhan 430081,Hubei,China)
出处
《烧结球团》
北大核心
2025年第3期78-86,共9页
Sintering and Pelletizing
基金
国家自然科学基金资助项目(51974212)。
关键词
球团工艺
粒度
生球性能
冶金性能
矿相结构
干燥成本
pelletizing process
particle size
green pellets performance
metallurgical properties
mineral phase structure
drying costs
