Effect of organic binders on the activation and properties of indurated magnetite pellets

In the ironmaking process, the addition of an organic binder to replace a portion of bentonite has the potential to improve the performance of pellets. The interaction between original bentonite (OB) and organic binder was investigated. Results indicated that the micromorphology of organic composite bentonite (OCB) became porous and the infrared difference spectrum exhibited a curved shape. In addition, the residual burning rates of OB and organic binder were determined to be 82.72% and 2.30%, respectively. Finally, the influence of OCB on the properties of pellets was investigated. The compressive strength of OCB-added green pellets (14.7 N per pellet) was better than that of OB-added pellets (10.3 N per pellet). Moreover, the range of melting temperature of OCB-added green pellets (173°C) was narrower than that of OB-added pellets (198°C). The compressive strength of OCB-added green pellets increased from 2156 to 3156 N per pellet with the increase in roasting temperature from 1200 to 1250°C.