煤基胶体复合黏结剂制备钒钛磁铁矿球团的研究

Study of preparation of vanadium-titanium magnetite pellets using coal-based colloidal composite binder

黏结剂是生产球团必不可少的原料之一,对球团矿的质量具有重要影响.煤基胶体复合黏结剂(3 Co-binder)是以低阶煤为主要原料制备的新型铁矿球团黏结剂,具有黏结性能好、用量少、价格低廉、在球团中残留量极低等特点和优势.首次介绍了煤基胶体复合黏结剂在钒钛磁铁矿氧化球团中的应用效果.实验室小型试验和模拟带式焙烧机扩大化试验结果表明:以1.0%(干基添加量0.14%)煤基胶体复合黏结剂完全替代1.5%改性膨润土,生球和焙烧球团质量均能满足要求,生球的落下强度为10.3次/0.5 m、抗压强度为16.9 N、爆裂温度为570℃;相比于改性膨润土,使用煤基胶体复合黏结剂制备球团矿的铁品位提高0.9%,球团矿强度达2409 N.煤基胶体复合黏结剂在氧化球团生产中的应用可推进高炉“精料”方针的落实,助力钢铁工业“双碳”目标的实现.

Binder is indispensable in the production of iron ore pellets.It can dramatically affect the quality of the pellets.The coal-based colloidal composite binder(3 Co-binder)is a novel binder prepared from low-rank coals for iron ore pelletizing.It has the advantages of good binding property,low dosage,low cost,and trace residues in pellets.For the first time,the effect of 3 Co-binder on the preparation of vanadium-titanium magnetite oxidized pellets was explored.The results of laboratory and straight grate-type pilot-scale tests show that the qualities of the green pellets and fired pellets could meet the industrial requirements.The drop strength,compressive strength,and the shock temperature of the green pellets reach 10.3 times per 0.5 m,10.3 N per pellet,and 570℃,respectively,when the addition of 1.5%modified bentonite is completely replaced by 1.0%3 Co-binder.Compared with the total iron content of the pellets prepared using bentonite,the counterpart in the pellets using 3 Co-binder is increased by 0.9%.Moreover,the compressive strength reaches as high as 2409 N per pellet.The novel 3 Co-binder will help to promote the quality of iron-making burden for achieving peak carbon dioxide emissions and carbon neutrality in the iron and steel industry.