再生铝工业铝灰渣特性及其贮存环境风险防控

Characteristics of aluminum ash slag in secondary aluminum industry and its storage environment risk prevention and control

针对再生铝工业铝灰渣贮存量大、处置难等现状所引发的环境污染问题,通过采集中国6家大型再生铝企业铝灰渣样品并进行物相定性和定量、遇水反应性等测试分析,研究了铝灰渣的成分和污染特性,并对铝灰渣的贮存环境风险防控提出建议。结果表明,再生铝企业铝灰渣中各物质含量从高到低依次是氧化铝、氮化铝、二氧化硅、铝、氧化镁、三氧化二铁、氧化钙、氟化铝以及微量的铜、锌等金属化合物,以铝单质及其化合物为主,总质量分数为74.8%~80.4%;所有铝灰渣样品均可以与水反应释放氨气,氨气比释放率为43.1~68.8 mg/kg;所有样品均可以与水反应释放氢气,氢气释放速率为0.5~1.5 L/(kg·h)。因此,铝灰渣的贮存过程应避免与水接触,并重点关注氨气和氢气的产生与扩散以及可能的事故风险。该研究结果可为再生铝工业铝灰渣的环境管理和贮存环境风险防控提供理论参考。

In view of the environmental pollution problems caused by the large storage capacity and difficult disposal of aluminum ash in recycled aluminum industry,the composition and pollution characteristics of aluminum ash were studied by collecting aluminum ash samples from 6 large recycled aluminum enterprises in China and testing and analyzing the phase qualitative and quantitative,water reactivity,etc.,and suggestions were put forward for the prevention and control of environmental risk of aluminum ash storage.The results showed that the contents of various substances in the aluminum ash of recycled aluminum enterprises from high to low were alumina,aluminum nitride,silicon dioxide,aluminum,magnesium oxide,iron oxide,calcium oxide,aluminum fluoride and trace copper,zinc and other heavy metal compounds,mainly aluminum and its compounds,with a total mass fraction of 74.8%~80.4%.All aluminum ash slag samples could react with water to release ammonia gas,and the ammonia gas specific release rate was 43.1~68.8 mg/kg;All samples could react with water to release hydrogen,and the hydrogen release rate was 0.5~1.5 L/(kg·h).Therefore,the storage process of aluminum slag should avoid contact with water,and pay attention to the generation and diffusion of ammonia and hydrogen,as well as possible accident risks.The research results could provide a theoretical reference for the environmental management of aluminum ash slag in the secondary aluminum industry and the prevention and control of storage environmental risks.