title: Study of PCDD/Fs distribution in fly ash, ash deposits, and bottom ash from a medical waste incinerator in China.
abstract: Over the past decades in China, the number of medical waste incinerators (MWIs) has been rising rapidly, causing emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). In this study, samples of fly ash, ash deposits, and bottom ash from typical MWIs were analyzed for PCDD/Fs and their distribution characteristics. Results showed international toxic equivalent (I-TEQ) values in the range of 6.9-67 ng I-TEQ/g in fly ash and ash deposits, whereas the concentration in bottom ash was extremely low (only 1.33 pg I-TEQ/g), yet the generation of PCDD/Fs was mostly de novo synthesis in fly ash and ash deposits according to the ratio of PCDFs to PCDDs; the major distribution differences of PCDD/Fs in fly ash was manifested by the content of toxic furan 2,3,7,8-TCDF but other toxic PCDD/Fs showed similar distribution. Other findings are that 2,3,4,7,8-PeCDF had the most contribution to TEQ concentration, and that the most abundant toxic furan congener is 1,2,3,4,6,7,8-HpCDF. Correlation analysis showed that there was no significant correlation between PCDD/Fs concentration and several other physical and chemical parameters.
  
  
  CONCLUSIONS
  This paper is of interest because it presents the emission performances of PCDD/Fs in ash from medical waste incineration in China. PCDD/F contents in fly ash and ash deposits vary between 6.9 and 67.3 ng I-TEQ/g. However, the concentration in bottom ash was extremely low (only 1.33 x 10(-3) ng I-TEQ/g). The fingerprints of PCDD/Fs in fly ash are almost similar, except for 2,3,7,8-TCDF. There is no marked correlation between PCDD/Fs and other physicochemical properties.
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, PR China.
authors.forename: Yingzhe
authors.initials: Y
authors.lastname: Du
authors.forename: Yuqi
authors.initials: Y
authors.lastname: Jin
authors.forename: Shengyong
authors.initials: S
authors.lastname: Lu
authors.forename: Zheng
authors.initials: Z
authors.lastname: Peng
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Li
authors.forename: Jianhua
authors.initials: J
authors.lastname: Yan
mesh_terms: D001572:Benzofurans / Q000032:analysis*; D002681:China; D060729:Coal Ash / Q000032:analysis; D000072338:Dibenzofurans, Polychlorinated; D005163:Factor Analysis, Statistical; D017745:Incineration; D008506:Medical Waste / Q000032:analysis; D017744:Medical Waste Disposal; D052638:Particulate Matter / Q000032:analysis*; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000032:analysis
chemical_list: D001572:Benzofurans; D060729:Coal Ash; D000072338:Dibenzofurans, Polychlorinated; D008506:Medical Waste; D017744:Medical Waste Disposal; D052638:Particulate Matter; D000072317:Polychlorinated Dibenzodioxins