垃圾焚烧飞灰中重金属和二恶英等痕量污染物分析

Trace Pollutant in MSW Incinerator Fly Ash: Heavy Metals and Dioxins

对国内外垃圾焚烧飞灰进行收集并着重利用GC MS、原子吸收光谱等手段对二恶英和重金属等痕量污染物进行系统研究,并结合国内外研究成果进行对比分析.结果表明,飞灰中不同种类重金属含量差异很大,Cu、Pb和Zn的含量较多,Cr的含量次之,Ni、Cd的含量较少.垃圾焚烧飞灰中二恶英含量差别很大,总含量在1.36～31.54ng/g.各种飞灰中二恶英的毒性当量更为悬殊.飞灰中二恶英和重金属含量及分布受垃圾成分、焚烧炉型、焚烧温度、停留时间等因素影响.

Municipal solid waste incinerator (MSWI) fly ash contains leachable heavy metals and toxic equivalents (TEQ) dioxins of high level, and is usually classified as a hazardous waste. Thus further detoxification and stabilization treatment must be applied to MSWI fly ash before disposing. The trace pollutants such as heavy metal and dioxins of MSWI fly ash have an important influence on selection of treatment technology. Dioxin and heavy metal in fly ashes collected from several MSW incinerators in China and France were studied. A comparative analysis with previous studies is performed. The results show that the content of each heavy metal is different. The contents of Cu, Pb and Zn are usually more than those of Cr, Ni and Cd in fly ash. The content of dioxins varies in the range of 1.36-31.54 ng/g. The results indicate that trace pollutant (such as heavy metal and dioxins) in MSWI fly ash is significantly affected by raw material, tape of furnace, incineration temperature and residence time.