保护性气氛下温度对镀锌废钢脱锌的影响

打开文本图片集

图分类号：TK11 文献标志码：A doi：10.12415/j.issn.1671-7872.24168

Effect Temperature on Dezincification Galvanized Steel Scrap under Protective Atmosphere

ZHANG A01 ， '， '， 1， '，MOU Wangzhong² （1. ， ，， 2. ， ，en 23， Stockholm 10044， Sweden）

Abstract：The hot-state experiments galvanized steel scrap were conducted using pyrometallurgical dezincification method under protective atmosphere.The influence temperature on dezincification was analyzed by characterization techniques including scanning electron microscopy （SEM）， energy dispersive ΔX ray spectroscopy （EDX）， X ray fluorescence （XRF）.The transformation zinc layer substrate in protective atmosphere was investigated， the dezincification mechanism was elucidated basedon metal evaporation rate difusion rate. The results show that under protective atmosphere conditions，localized oxidation galvanized steel scrap surfaces occurs at 850‰ due to residual oxygen， forming yellow ZnO . As temperature rises to 925‰ ， surface blistering is observed， upon further heating to 1 000c ，the ZnO gradually diminishes until complete disappearance. The mass thickness galvanized steel scrap increase after 850°C due to zinc oxidation， but show significant reduction at 950°C when substantial zinc removal occurs. The surface zinc content decreases from 65.69% to 4.00% achieving a dezincification rate 93.9% . Within specific temperature ranges，dezincification efficiency is significantly enhanced with increasing temperature. When reaching zinc's boiling point （907°C） ，rapid zinc vaporization ruptures the surface oxide film，causing continuous expansion dezincification Zzones until complete surface zinc removal isaccomplished.Considering both dezincification efficiency industrialcosts，theoptimal dezincification temperature is determined to be 950‰ ：

Keywords： galvanized scrap; fire dezincification; nitrogen protection; zinc oxidation; evaporation; resource recovery

伴随钢铁工业的持续发展，我国废钢产量不断攀升，2024年已达2.5亿t，占全球总产量一半以上。（剩余11874字）