内蒙古某高硫高碱度磁铁精矿球团焙烧脱硫机理研究

Study on pellet induration desulphurization mechanism of high sulphur and high basicity magnetite concentrate from Inner Mongolia

以内蒙古某高硫高碱度磁铁精矿为原料进行实验室球团焙烧试验,根据试验结果、化学分析及对球团剖面的断面成像观察对其焙烧脱硫机理进行了研究。结果表明,延长预热时间能有效提高预热球团氧化率,降低成品球Fe O和S含量,且预热球和成品球强度均增强;鼓风预热能有效减少氧化时间;预热球S含量随预热时间的延长基本不变,但硫化物残余量降低,影响熟球质量的最大因素是预热球中硫化物残量而非SO2-4的含量;预热温度越高,预热球团脱硫效果越好,成品球质量也越好,但预热球Fe O含量在1 000℃陡然上升。

The laboratory pellet induration test was carried out using high sulphur and high basicity magnetite concentrate from Inner Mongolia as raw materials,according to the results of the test,chemical analysis and microscopic observation of pellet section,the induration desulfurization mechanism was studied. The results show that,extending the preheating time can improve the oxidation rate of preheated pellets and reduce Fe O and S content of pellet product,the compressive strength of preheated pellet and product pellet are both enhanced. Blast preheating can effectively reduce the oxidation time. The sulfur content of preheated ball basically remains unchanged with the extension of preheating time,but the sulfide residue is reduced. The most important factor that affects the quality of roasted ball is the content of residual sulfide rather than SO2-4content. The higher the preheating temperature is,the desulfurization efficiency of preheating pellets is better,so is the quality of indurated pellets,but the content of Fe O rises abruptly at 1 000 ℃.