为了研究含铬浸出渣的调质解毒机理,建立了CaO-MgO-FeO-Na2O-SiO2-Al2O3-Cr2O3七元渣系活度模型,基于共存理论的活度模型得出了铬渣中主要组分及复合氧化物在不同条件下的活度。所得的结果表明,铬渣中Cr2O3主要形成了Na2Cr2O4和CaCr2O4,这两种复合氧化物不稳定,在自然环境中分别会被氧化为水溶性的铬酸钠(Na2CrO4)和酸溶性的铬酸钙(CaCrO4),释放出具有强毒性的Cr(Ⅵ),是造成铬污染的主要原因。温度、碱度以及渣中FeO含量都能影响渣系组分的活度。在1700K下,将铬渣碱度调至1.14,并加入30%的FeO能够使Cr2O3的有效固定率提高至88.2%,基本实现了铬渣的解毒。
A model of seven-component slag system of chrome slag containing CaO,MgO,FeO,Na2O,SiO2,Al2O3 and Cr2O3 was built to research its detoxification.This model was based on coexistence theory,by which each component's activity of the slag system in different conditions could be got.Results of the model showed that Cr2O3 is mainly formed into Na2Cr2O4 and CaCr2O4,which were both unstable composite oxides.In the notural environmental condition,they could be oxidized to water-soluble sodium chromate and acid-soluble calcium chromate.They both could release Cr(Ⅵ) with strong toxicity,which is the main cause of pollution by chrome.Temperature,basicity and FeO all have influence on components' activity of the slag system.A temperature of 1700K,when adjusting the slag basicity to 1.14 and adding in 30% FeO,percentage of Cr2O3 fixed into spinel could reach 88.2%.The goal of detoxification of chrome slag was basically achieved.