加热预处理对浮选赤铁矿粉造球性能的影响

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

为查明浮选赤铁矿粉球团在高温干燥过程中爆裂温度低的机理,利用傅里叶红外光谱仪对生产过程中的3种赤铁矿粉的红外光谱进行了对比,试验发现爆裂温度低的球团所用赤铁矿粉中油酸钠红外光谱吸收峰明显高于其他2种矿粉。进一步的试验结果表明,铁矿粉经150℃以上干燥预处理后,油酸钠红外光谱吸收峰变弱,造球后球团的爆裂温度提高。铁矿粉中残留的油酸钠有机药剂附着在矿粉表面,使铁矿粉的疏水性增强,导致球团干燥速率提高,容易爆裂。对铁矿粉进行高温加热预处理后,矿粉表面残留的油酸钠药剂减少,提高了生球的爆裂温度。

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.