CaCO3分解对熔剂性球团强度的影响

 铁精粉在预热、焙烧过程中会伴随着热量的变化,这一行为会影响球团矿的抗压强度。为探究熔剂中CaCO₃分解对熔剂性球团强度的影响机理。通过TG-DSC分析技术,研究铁精粉、不同铁精粉混合、铁精粉与熔剂混合交互作用下的热量变化规律,以及热量变化对球团矿抗压强度的影响,建立热量变化与焙烧温度的匹配关系。通过调节焙烧温度、焙烧时间使熔剂性球团达到普通酸性球强度。结果表明,铁精粉之间的交互作用并不明显;在700~850 ℃铁精粉与石灰石粉发生交互作用,磁铁精粉的氧化反应对石灰石的分解有一定的促进作用,TG曲线的试验值较理论值出现前移;石灰石分解行为对磁铁矿球团氧化固结的抑制作用明显,可以通过延长焙烧时间使熔剂性球团达到普通酸性球强度;在提高焙烧温度后,熔剂性球团强度明显增强,相较于普通酸性球团增加约50 N/个(球)。

Effect of CaCO3 decomposition on fluxed pellets strength

During the preheating and roasting process of iron concentrate powder, the heat will change and it will affect the compressive strength of pellets. To explore the mechanism of the decomposition of CaCO₃ in flux on the strength of flux pellets Through TG-DSC analysis technology, the law of heat change under the interaction of iron powder, different iron powder mixed, iron powder mixed with flux, and the effect of heat change on the compressive strength of pellets were studied. By adjusting the calcination temperature and time, the flux pellets could reach the strength of ordinary acid pellets. The results showed that the interaction between iron powder was not obvious. From 700 to 850 ℃, the iron concentrate powder interacts with limestone powder, and the oxidation reaction of magnet fine powder can promote the decomposition of limestone. The experimental value of the TG curve appeared earlier than the theoretical value. Limestone decomposition behavior had an obvious inhibitory effect on the oxidation and consolidation of magnetite pellets. The flux pellets could reach the strength of ordinary acid pellets by prolonging the calcination time. After increasing the calcination temperature, the strength of flux pellets was obviously enhanced, which was increased by about 50 N/ball compared to ordinary acid pellets.