化学成分对铁酸盐烧结液相流动性的影响

铁酸盐液相是高碱度烧结矿固结的基础,适宜的流动性有利于烧结液相有效黏结和保证料层透气性。为了明晰化学成分对其液相流动性的影响,采用微型烧结法研究了Fe2O3与CaO的摩尔比为1.0、1.5和2.0时铁酸盐的液相流动特征,以及SiO2对这3类铁酸盐液相流动性的影响规律,在此基础上,探讨了促使高流动性铁酸盐生成条件下烧结原料中黏附粉化学成分的选取原则。结果表明,铁酸盐液相流动性随其中CaO量的增加而升高;随着SiO2含量的增加,摩尔比为1.0的铁酸盐液相流动性呈现先增加后降低的趋势,且在高硅低碱度下仍具有较高的流动性;摩尔比为1.5的铁酸盐液相流动性变化规律与高钙铁酸盐相似,但SiO2的质量分数大于5.5%、二元碱度低于3.26时,液相流动性则降低;摩尔比为2.0的铁酸盐液相流动性随SiO2含量的增加呈单调降低趋势。

Influence of chemical composition on liquid fluidity of ferrite

Ferrite liquid is the foundation of solidification for high basicity sinters, and proper fluidity of sintering liquid phase is benefit for effective bonding and guarantees high permeability of sintering bed. In order to determine the influence of chemical composition on the fluidity of ferrite liquid, micro sintering method was adopted to study the flow characteristic of ferrite liquids with mole ratios of Fe2O3and CaO of 1.0, 1.5 and 2.0, and the influence law of silicon dioxide on the flowing characteristics of the three was researched as well. On the above bases, the choice principle of chemical composition of adhesive powder in sintering mixture to promote fluidity of ferrite liquid was discussed. The results indicate that the fluidity of ferrite liquid increases with CaO content increasing. As SiO2 content increases, the fluidity of ferrite liquid with the mole ratio of 1.0 increases first and then reduces and is still relatively high at high silicon content and low alkalinity. Change rule of fluidity of ferrite with the mole ratio of 1.5 is similar to high calcium ferrite, nevertheless the fluidity of ferrite liquid decreases when wSiO2 is higher than 5.5% and binary basicity is lower than 3.26. For ferrite with the mole ratio of 2.0, its fluidity reduces as SiO2 content increases.