含砷冶炼废渣高温烧结过程砷的迁移特性

Vaporization characteristics of arsenic during sintering process of smelting slag containing arsenic

研究了烧结温度和烧结时间对含砷冶炼废渣烧结过程中砷的迁移特性的影响。烧结条件为在10 MPa下加压成型,进空气流量为2 000 mL/min,烧结温度1 000～1 350℃,烧结时间5～120 min。结果表明,烧结过程中存在砷的挥发,但烧结前后砷的总量变化不大,砷的固化率均保持在90%以上。毒性浸出实验表明,不同的烧结条件对烧结体中砷的毒性浸出有重要的影响,从烧结体的环境安全性考虑,最佳的烧结温度和时间分别为1 200℃和45 min。

An experimental work was carried out to investigate the effect of sintering temperature and sintering time on the stabilization of arsenic during a sintering process of smelting slag containing arsenic. The raw materials were shaped under the pressure of 10 MPa and exposed at 1 000 - 1 350℃ for 5 - 120 rain with the air flow rate of 2 000 mL/min. The results showed that arsenic （As） could volatilize in the sintering process, however, there were not significant differences between the total amount of As before and after sintering, and the stabi- lization rate of As were both above 90%. The leaching results of the horizontal vibration method and TCLP showed that sintering condition had important influence on the leaching concentration of As. Considering the product＇ s environmental safety, the best sinterin~ temperature and sintering time were 1 200℃ and 45 min. respectively.