Abstract：To investigate the influence of layer thickness of iron powder on reducing efficiency in reducing furnace with H2 as reducing agent, the diffusion kinetic model of iron powder reduction was established using coupling kinetic model of FeO reduction and reducing gas oxidation. For 0.2 mm sponge iron powder with 0.74% remaining oxygen, the reduction condition is as follows: layer depth of 30 mm, heating time of 1 h,temperature of 850-900 ℃ and hydrogen flow of 30 Nm3/(t∙h). The remaining oxygen of product is 0.25%, which is coincidence with the calculation result (0.27%). The remaining oxygen in iron powder can be reduced easily. The hydrogen in the hydrogen reduction furnace penetrates into the iron powder layer, and the iron powder is reduced layer by layer from top to bottom. For 30 mm layer thickness, penetrating depth of hydrogen is about 25 mm, and another 5 mm thickness iron powder near the bottom can not be reduced. The remaining oxygen increases, the utilization rate of hydrogen and the yield decease with increasing layer thickness. When layer thickness decreases from 3 cm to 2 cm, reducing time will shorten 50%, yield will improve 33%, and consumption of H2 will decrease 50%.
郭培民, 赵沛, 孔令兵, 王磊. 料层厚度对粉末冶金用铁粉氢还原的影响[J]. 粉末冶金材料科学与工程, 2018, 23(3): 261-265.
GUO Peimin, ZHAO Pei, KONG Lingbing, WANG Lei. Effect of layer thickness on hydrogen reduction of iron powder in powder metallurgy. Materials Science and Engineering of Powder Metallurgy, 2018, 23(3): 261-265.
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2018, Vol. 23 
