Unintentional production of persistent chlorinated and brominated organic pollutants during iron ore sintering processes

• Published in: Journal of hazardous materials 2017-06, Vol.331, p.63-70
• Main Authors: Li, Sumei, Liu, Guorui, Zheng, Minghui, Liu, Wenbin, Li, Jinhui, Wang, Mei, Li, Changliang, Chen, Yuan
• Format: Article
• Language: English
• Subjects: Dioxins; Iron ore sintering; Persistent organic pollutants; Polychlorinated naphthalenes; Profiles
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2017.02.027

•PBDD/F emission factors were derived for six iron ore sintering plants in China.•These emission factors are important for compiling the global emission inventory.•Significant correlations among POPs suggest the possibility of synergetic reduction.•PCDD/Fs were dominant contributors to total toxic equivalents of multiple POPs. Iron ore sintering (SNT) processes are major sources of unintentionally produced chlorinated persistent organic pollutants (POPs), including polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), and polychlorinated naphthalenes (PCNs). However, few studies of emissions of brominated POPs, such as polybrominated dibenzo-p-dioxins/dibenzofurans (PBDD/Fs) and polybrominated diphenyl ethers (PBDEs), during SNT have been performed. Stack gas and fly ash samples from six typical SNT plants in China were collected and analyzed to determine the concentrations and profiles of PCDD/Fs, PCBs, PCNs, PBDD/Fs, and PBDEs, as well as any correlations among these compounds. The PCDD/F, PCB, PCN, PBDD/F, and PBDE emission factors were 2.47, 0.61, 552, 0.32, and 107μgt−1, respectively (109, 4.07, 10.4, 4.41 and 0.02ng toxic equivalents t−1, respectively). PCBs were the most abundant compounds by mass, while PCNs were the next most abundant, contributing 51% and 42% to the total POP concentration, respectively. However, PCDD/Fs were the dominant contributors to the chlorinated and brominated POP toxic equivalent concentrations, contributing 89% to the total toxic equivalent concentration. The PCDD/F and other chlorinated and brominated POP concentrations were positively correlated, indicating that chlorinated and brominated POP emissions could be synergistically decreased using the best available technologies/best environmental practices already developed for PCDD/Fs.