含碳铬铁矿粉在微波场中的升温特性
Temperature-rising characteristic of chromite ore fines containing coal in a microwave field
-
摘要: 采用微波加热法避免传统加热方式带来的粉状物料传热传质不均匀的现象.利用微波冶金炉,针对含碳铬铁矿粉在微波场中的升温特性进行了研究.结果表明,含碳铬铁矿粉在频率2.450GHz的微波场中具有良好的升温特性.在微波加热功率10kW、含碳铬铁矿粉1kg的条件下,含碳铬铁矿粉在7min内温度可升至1100℃,升温速率为157.1℃·min-1;而含碳磁铁矿粉在10min内温度升至1000℃,升温速率仅为100℃·min-1.提高配碳比,可提高含碳铬铁矿粉的升温速率和降低轻烧钙质石灰粉对物料升温速率的影响.Abstract: The microwave heating technique can avoid the non-homogeneous phenomenon of transferring heat and mass in pulverous ore materials by conventional heating. The temperature-rising characteristic of chromite ore fines containing coal in a microwave field was experimentally investigated with a microwave metallurgy oven. The results showed that chromite ore fines containing coal had a better temperature-rising characteristic in the microwave field of 2.45 GHz in frequency. Under the condition of the microwave power of 10 kW and the ore fines' mass of 1 kg, chromite ore fines containing coal reached 1 100℃ in 7 min with a temperature-rising rate of 157.1℃·min-1 whereas magnetite ore fines containing coal reached 1000℃ in 10 min with a tempera-ture-rising rate of only 100℃·min-1. Increasing the carbon-oxygen mole ratio can enhance the heating effect of chromite ore fines containing coal and reduce the effect of lime addition on the temperature-rising rate.