Temperature rising characteristics of iron and iron oxides in microwave field

The major advantages of microwave heating are rapid heat transfer, volumetric property, immediacy and selectivity, in addition, compactness of equipment, high-controlling accuracy and pollution-free. However, its development for the industrial application is very slow, especially in high temperature areas where there is no mature case of industrial production. One important reason is lag of studying mechanism of microwave interaction with materials (particulates). Therefore, it was of great significance in studying temperature rising characteristics of iron and iron oxides in microwave field, not only their coupling ability with microwave for applying microwave energy to facilitate intelligently in different iron phases can be understood, but also temperature rise mechanism of iron and iron oxides in microwave field by explored several major factors of heating. The electromagnetic properties in room temperature results show that, Fe > Fe3O4 > FeO > Fe2O3. Because of the physical properties changed in the process of microwave heating to 1050°C, the speed of heating is: Fe3O4 > FeO ≈ Fe2O3 > Fe. Briquette has a faster heating rate compares with powder in microwave field, but it does not change the thermal runaway phenomenon. SEM results show that the material is conducive to microwave penetration and absorption when it has loose structure, developed holes and irregular granules.