Effect of heating pretreatment on ballability of hematite concentrate with flotation process

The experiments were carried out to investigate the mechanism of lower cracking temperature of green pellet made by iron concentrate with flotation process. The results of Fourier transform infrared spectroscopy??FTIR?? analysis indicate that the iron concentrate of green pellet with lowest cracking temperature has the strongest sodium oleate transmittance of infrared spectrum. When the iron concentrate is heated to 70, 150 and 250??, respectively, the sodium oleate transmittance weakens and the cracking temperature of green pellet increases observably. The sodium oleate that attached to the surface of iron concentrate make the iron concentrate more hydrophobic, which leads to faster vaporizing speed of pellets moisture and lower cracking temperature of green pellet. The pretreatment of heating iron concentrate above 150?? can effectively decrease the residual sodium oleate on the surface of iron concentrate and improve the cracking temperature of green pellet.