高温自蔓延还原解毒固化铬渣技术研究  

Study on Reducing and Solidifying Chromium Slag by SHS Technology

作　　者：徐中慧[1,2,3] 肖博[2] 吴丹丹[2] 王海龙[2] 郑磊[2] 肖鹏[2] 王德军[2] 

机构地区：[1]西南科技大学固体废物处理与资源化教育部重点实验室 [2]西南科技大学非煤矿山安全技术四川省高等学校重点实验室 [3]西南科技大学核废物与环境安全国防重点学科实验室,四川绵阳621010

出　　处：《环境科学与技术》2014年第10期140-143,共4页Environmental Science & Technology

基　　金：核废物与环境安全国防重点学科实验室开放基金(12zxnp03);四川省教育厅青年基金(13ZB0183);固体废物处理与资源化教育部重点实验室平台基金(13zxgk05)

摘　　要：采用高温自蔓延技术处置铬渣,探讨了高温自蔓延技术还原解毒固化铬渣的机制。以铝粉和三氧化二铁作铝热剂,与铬渣充分混合,用镁条点燃引发自蔓延反应,最终得到铬渣固化体。实验结果表明:高温自蔓延技术能有效固化铬渣,铬渣的掺渣率高达44.94%。浸出实验结果表明:A组(铬渣原样)铬渣固化体总铬浸出浓度未检出;B组(铬渣原样+重铬酸钾)铬渣固化体总铬浸出浓度为0.117 76 mg/L,远远低于国标(GB 5085.3-2007)限值15 mg/L,六价铬浸出浓度未检出。XRD分析表明:铬渣还原解毒固化机制主要是六价铬在自蔓延反应中被还原为三价铬,再与其他金属化合物在高温熔融状态下生成含铬尖晶石,铬以离子键Cr—O的形式参与尖晶石的晶格形成。SHS technology is used for disposal of chromium slag, the detoxification mechanism and the solidification mechanism are explored. Aluminum and ferric oxide is used as a thermite, fully mixed with the chromium slag. The mixture is ignited by magnesium rod to begin with self propagating reaction, then getting chromium residue product. The experimental results show that chromium slag can be solidified effectively by SHS technology, and chromium slag content of chromium residue reaches 44.94%. The leaching experiment results show that the leaching concentration of total chromium of group A is not detected and the leaching concentration of total chromium of group B is 0.117 76 mg/L. Six chromium leaching concentration of group B is not detected. XRD analysis show that the detoxification mechanism and the solidification mechanism of chromium slag is that six chromium is reduced to trivalent chromium in the self propagating, then generate spinel with other metal compounds in high temperature molten state. Chromium is involved in the formation of spinel lattice by ionic bond in the form of Cr-O.

关 键 词：铬渣 高温自蔓延技术 固化 浸出毒性 机制 

分 类 号：X756[环境科学与工程—环境工程]