再生铝?铅生产企业PCDD/Fs排放浓度与特征

研究了国内3家再生金属企业排放烟气和飞灰中PCDD/Fs排放浓度和同系物分布特征,其中两家再生铝企业?一家再生铅企业.研究结果显示:两家再生铝企业排放烟气中PCDD/Fs毒性当量浓度( I-TEQ)分别为2.14和0.88ng TEQ/Nm3,飞灰中分别为33.90和0.77ng TEQ/g;再生铅企业排放烟气和飞灰中PCDD/Fs毒性当量浓度分别为0.037ng TEQ/Nm3和0.014ng TEQ/g;两家再生铝企业排放烟气中PCDD/Fs同族体分布存在较大差异,而飞灰中PCDD/Fs同族体分布却十分相似;再生铅?铝企业排放的PCDD/Fs同系物分布特征差异较明显;且根据PCDFs与PCDDs总浓度比值大于1可以判断,二者排放PCDD/Fs的形成机理都以从头合成为主.

Concentration and characterization of PCDD/Fs emission from secondary lead and aluminum metallurgy plants

The concentration and characterization in stack gas and fly ash from two secondary aluminum metallurgy plants and one secondary lead metallurgy plant were investigated.The results showed that the concentrations of PCDD/Fs in stack gas released from the two secondary aluminum metallurgy plants were 2.14 and 0.88 ng TEQ/Nm3,respectively,the corresponding concentrations in fly ash were 33.90 and 0.77 ng TEQ/g,respectively.The PCDD/Fs concentrations of stack gas and fly ash from the secondary lead metallurgy plant was 0.037 ng TEQ/Nm3 and 0.014 ng TEQ/g,respectively.Although the homologue distributions of PCDD/Fs in stack gas from the two secondary aluminum metallurgy plants were different,they were similar in fly ash.The congener distributions of PCDD/Fs were quite different between secondary aluminum and lead metallurgy plants.Due to the ratio of total PCDF/PCDD was above one,de novo synthesis may be the main formation mechanism of PCDD/Fs emission from secondary lead and aluminum metallurgies.