锰块矿焙烧试验研究及带式焙烧机工艺探讨

Experimental research on manganese lump ore roasting and discussion on straight grate technology

我国是锰铁合金的主要进口国和消费国,但我国锰块矿品位较低,冶炼成本高,处理工艺单一。为提高锰块矿品位,降低锰合金冶炼的燃料消耗,减少生产成本,本文通过正交试验方法对锰块矿干燥、预热和焙烧的工艺制度进行研究,分析其焙烧的工艺特点及难点,研究其系统焙烧温度和O_(2)与CO_(2)分压对MnCO_(3)分解反应的影响,最终找出其合理的焙烧工艺。结果表明:当锰块矿粒度为15~40 mm、干燥温度为400℃、干燥时间为3.0 min、预热I段(温度为550℃、时间为3.0 min)、预热II段(温度为900℃、时间为10 min)、焙烧温度为1100℃、焙烧时间为10 min、均热温度为950℃,均热时间为6 min时,锰块矿焙烧效果最佳,焙烧后锰块矿中TMn质量分数由21.34%升至32.32%,碳脱除率达98.94%,烧损率为28.40%。

China is the main importer and consumer of manganeseirom with low grade of manganese lump ore,high smelting cost and single treatment process.In order to improve the grade of manganese lump ore,reduce the fuel consumption of manganeseirom smelting and its production cost,the process system of drying,preheating and roasting manganese lump ore is studied by orthogonal test method,the process characteristics and difficulties of roasting are analyzed,and the effects of the roasting temperature and the partial pressure of O_(2)and CO_(2)on the decomposition reaction of MnCO_(3)are studied to finally find out its reasonable roasting technology.The results show that,when the particle size of manganese lump is 15~40 mm,the drying temperature is 400℃,the drying time is 3.0 min,the preheating temperature section I is 550℃,the time is 3.0 min,the preheating section II temperature is 900℃,the time is 10 min,the roasting temperature is 1100℃,the roasting time is 10 min,the soaking temperature is 950℃,and the soaking time is 6 min,the roasting effect of manganese lump ore is the best,the TMn mass fraction in manganese lump ore is increased from 21.34%to 32.32%,the carbon removal rate is 98.94%,and the burn-off rate is 28.40%.