再生铝工业固体废物成分组成与污染特性研究

Study on composition and pollution characteristics of solid waste in recycled aluminum industry

采集了5家国内具有代表性的大型再生铝企业不同生产工艺环节排放的固体废物样品:铝灰渣、除尘灰和水洗污泥,并对其化学成分组成、重金属浸出毒性、二噁英毒性含量等进行分析研究。再生铝固体废物由Al、O、C、Si、Mg、Ca、Fe等7种主要元素以及微量的Cu、Zn、Ba、Cr、Ni、Pb等重金属元素组成,模拟酸性降水条件下,存在多种重金属离子浸出,部分浓度甚至超过危险废物浸出毒性标准,对土壤和地下水环境具有严重的污染风险;特别是颗粒细小的除尘灰还含有熔炼过程中有机杂质不完全燃烧产生的二噁英类物质,其浓度最高可达173517ng/kg(12807ng TEQ/kg)。大量排放的除尘灰不仅影响空气质量,而且可通过呼吸系统进入人体,对人体健康造成严重危害。因此,应采取妥善处理处置措施,有效控制再生铝工业固体废物对环境造成污染。

The composition, heavy metal leaching and dioxins contents of solid waste： aluminum dross, bag house dust and sludge collected from five large - scale recycled aluminum enterprises in China were analyzed. The solid waste is mainly composed of Al, O, C, Si, Mg, Ca and Fe elements and a trace of heavy metals such as Cu, Zn, Ba, Cr, Ni and Pb. Under the condition of simulated acidic precipitation, there are many kinds of heavy metal ions leaching, some concentrations even exceed the leaching toxicity standard of hazardous wastes, which has serious pollution risk to soil and groundwater environ- ment. In particular, the fine dust also contains dioxin -like substances generated by incomplete burning of organic impurities in smelting process, and its concentration is up to 173517ng / kg （ 12807ngTEQ / kg）. A large number of dusts shall not only affect the air quality, but also get into the human body through the respiratory system, causing serious harm to human health. Therefore, proper disposal measures should be taken to effectively control the envi- ronmental pollution of recycled aluminum industry.