应用同位素稀释、高分辨气相色谱-质谱联用技术测定了国内3种类型水泥窑(机械立窑、湿法旋窑和新型干法旋窑)以及生活垃圾焚烧炉和医疗垃圾焚烧炉的除尘器捕集灰中PCDD/Fs、PCBs和PCNs的浓度和毒性当量,比较了同族体和同类物的分布特征.结果表明,水泥窑除尘器捕集灰中二嗯英及其类似物PCDD/Fs、PCBs和PCNs的总毒性当量(以TEQ计)分别在4.0~62、0.069~3.9和0.47~2.8ng·k^-11之间,远小于垃圾焚烧炉除尘器捕集灰.占优势的PCDD/Fs同族体都是TCDFs,相对较多的2,3,7,8位氯取代二嘿英同类物有OCDD、2,3,7,8-TCDF、1,2,3,4,6,7,8-HpCDF;水泥窑除尘器捕集灰中PCBs同族体的分布特征与垃圾炉相似,占优势的同族体都是四氯联苯,含量较高的共平面PCBs同类物有PCB77、PCB105、PCB118;不同窑型水泥窑除尘器捕集灰中PCNs同族体分布特征相似,占优势的同族体都是四氯萘,没有检测到八氯萘的存在,含量较高的二嘿英类毒性PCNs同类物是毒性最大的PCN66/67.
The concentrations and toxic equivalent (TEQ) values of PCDD/Fs, PCBs and PCNs in fly ash collected from three types of cement kilns (vertical shaft kiln,wet-process rotary kiln and dry-process rotary kiln) and two types of waste incinerators were determined, and the patterns of homologues and congeners were compared.The results showed that the total TEQ of PCDD/Fs,PCBs and PCNs in cement kiln fly ash,which were in the range of 4.0-62, 0.069-3.9 and 0.47-2.8 ng· kg^-1 respectively, were much lower than that of fly ash from waste incinerators. In cement kiln fly ash, the predominating PCDD/Fs homologues were TCDFs, and the chief 2, 3, 7, 8-PCDD/Fs congeners were OCDD, 2, 3, 7, 8-TCDF and 1, 2, 3, 4, 6, 7, 8-HpCDF.The patterns of PCBs homologues in cement kiln fly ash were similar to those of waste incinerators in which TeCB were predominating homologues. PCB77, PCBI05, PCB118 were at higher concentrations than other co-polar PCBs. Different types of cement kiln fly ash presented similar PCNs homologue patterns. The predominant homologues were TeCN, whereas OcCN were not detected. PCN 66/67 which has dioxin like toxity was the most abundant congener in all fly ash.