Study on Chromium Elution from Stainless Steel Slag Heated in Different Atmosphere
Stainless steel slag is the by-product of stainless steel making,while the chromium contained in stainless steel slag would hinder the utilization of the slag due to the elution of hexavalent chromium.In this paper,the effect of atmosphere on the chromium leachability from stainless steel slags during the cooling process was investigated and the efficient method for controlling the dissolution of chromium was discussed in order to provide theoretical basis for promoting the utilization of stainless steel slag.The experiments were carried out in a muffle furnace and an induction furnace.The stainless steel slag samples were heated at 600℃ and 1000℃ for 2h.The treated samples were used to leaching test according to the standard procedure,prEN12457-2,and leaching solution was tested using Inductively Coupled Plasma Emission Spectrometer(ICP).The results show that the oxidation atmosphere enhances the leachability of chromium,and the dissolved amount of chromium increases with the rise of temperature.For the sample S2,the oxidation of chromium in the oxidizing atmosphere makes that the value of chromium leaching increases from 1.80mg/L to 56.90mg/L when the temperature rises from 600℃ to 1000℃.The reductive atmosphere could suppress the leaching of chromium because CaCrO4 could be decomposed into calcium oxide and chromium oxide by CO.When S1 was first oxidized at 600℃ in muffle furnace,and then reduced at 600℃ in induction furnace,the content of chromium leaching reduced from 2.15mg/l to 0.15mg/l.When the sample was treated in the same way at 1000℃,the Cr concentration in the leachate changed from 8.73mg/l to 0.37mg/l.Once the hexavalent chromium existed,it is difficult to reduce the Cr6+to Cr3+completely.Thus,it is necessary to adopt a neutral or reductive atmosphere for slag cooling in order to restrain the formation of hexavalent chromium.
atmosphere oxidation hexavalent chromium stainless steel slag leaching
Jianli LI Rui LI Kai YU Anjun XU Hangyu ZHU Zhengliang XUE
Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Wuhan Unive School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beij
国际会议
the 6th International Congress on the Science and Technology of Steelmaking,ICS2015(第六届国际炼钢科技大会)
北京
英文
954-957
2015-05-12（万方平台首次上网日期，不代表论文的发表时间）