新型有机黏结剂HC用于制备冷压球团的研究

Study on preparation of cold-press pellets using new style organic binder HC

采用新型有机黏结剂(HC)代替膨润土制备冷压球团的方法,得到高冶金性能的入炉原料.随着HC和膨润土用量(质量分数,下同)的增加,铁矿球团和含碳球团生球的抗压强度均呈逐渐升高的趋势,当黏结剂用量为1.5%时,抗压强度分别为5264,2012N/个;生球落下强度随着HC用量的增加而增加,但随着膨润土用量的增加变化趋势不明显.通过研究生球微观结构发现,膨润土附在铁矿颗粒表面且成片聚集,而HC能完全浸润在铁矿颗粒附近且大部分嵌入矿粉颗粒内部,显著提高了生球的落下强度.添加0.3%的HC与添加0.6%~1.2%的膨润土相比生球性能相近,同时球团铁品位较高,因此HC有望部分或全部代替膨润土.

In this study, a kind of new organic binder(HC) was used to replace bentonite to prepare iron ore-coal composite pellets by cold briquetting. The strength and microstructure of pellets were analyzed by universal press, metallographic microscope and SEM-EDS. With the increase of HC and bentonite content(mass fraction, the same below), the compressive strength of iron ore pellets and iron ore-coal composite pellets increases gradually. When the binder content was 1.5%, the compressive strength was 5 264 N and 2 012 N. The dropping strength increased with the increase of HC dosage, but the increase trend was not obvious with the increase of bentonite. In the microstructure, bentonite was attached to the surface of iron ore particles and agglomerated in sheets. However, HC could completely infiltrate nearby the iron ore particles and most of them were embedded in the ore particles, which significantly improves the dropping strength. The addition of 0.3% HC is similar to the addition of 0.6%~1.2% bentonite pellets, which increases the TFe conent. Therefore, it is feasible for HC to substitute bentonite partially or completely.