Identification and characterization of the atmospheric emission of polychlorinated naphthalenes from electric arc furnaces

Abstract

Electric arc furnaces (EAF) are well recognized as significant sources of dioxins. EAFs have also been speculated to be sources of polychlorinated naphthalenes (PCNs) due to the close correlation between dioxin and PCN formation. However, assessment on PCN emissions from EAFs has not been carried out. The primary aim of this preliminary study is to identify and characterize the atmospheric emission of PCNs from EAFs. In this preliminary study, stack gas samples from two typical EAFs with different scales (EAF-1, 160 t batch −1 ; and EAF-2, 60 t batch −1 ) were collected by automatic isokinetic sampling technique, and PCN congeners in samples were analyzed by isotope dilution high-resolution gas chromatography combined with high-resolution mass spectrometry method. Emission concentrations of PCNs were 458 and 1,099 ng m −3 for EAF-1 and EAF-2, respectively. The emission factors of PCNs to air were 21.6 and 30.1 ng toxic equivalent t −1 for EAF-1 and EAF-2, respectively, which suggested that EAF is an important source of PCN release. With regard to the characteristics of PCNs from EAFs, lower chlorinated homologues were dominant. The PCN congeners comprised of CN27/30, CN52/60, CN66/67, and CN73 were the most abundant congeners for tetra-, penta-, hexa-, and hepta-chlorinated homologues, respectively. EAFs were identified to be an important PCN source, and the obtained data are useful for developing a PCN inventory. The congener profiles of PCNs presented here might provide helpful information for identifying the specific sources of PCNs emitted from EAFs.

Estimation and characterization of unintentionally produced persistent organic pollutant emission from converter steelmaking processes

“…It would have been, at least partly, caused by the fraction of semivolatile compounds adsorbed to particles being higher for less volatile congeners (Lohmann and Jones 1998). The 2378-PCDD/F, dl-PCB, and dl-PCN fingerprints in the converter steelmaking process were very similar to fingerprints found in other thermal processes including SNT, secondary copper smelting, and EAF processes (Hu et al 2013a;Liu et al 2012a, b).…”

“…SNT and EAFs, used in integrated steelmaking processes, are thought to be two of the main global UP-POP sources (Aries et al 2006;Liu et al 2012a, b;Tian et al 2012;Yu et al 2012). UP-POP emissions from SNT have been found to be comparable to those from coking, but lower than those from thermal wire reclamation and copper secondary metallurgical processes (Hu et al 2013a, b;Liu et al 2009Liu et al , 2012bNie et al 2012a, b).…”

Case study of polychlorinated naphthalene emissions and factors influencing emission variations in secondary aluminum production

“…Polychlorinated naphthalenes (PCNs) are persistent organic pollutants (POPs), and are ubiquitous in environmental matrices and utors to PCN emissions are thermal-related industries, including waste incineration, coking processes, and metallurgical processes such as secondary nonferrous smelting, iron ore sintering, and steelmaking using electric arc furnaces [7][8][9][10][11]. However, investigations on developing control measures aimed at reducing PCN emissions from these industrial processes are still scarce.…”

Occurrence, profile and possible sources of PCNs in Hong Kong soils, and a comparison with PCBs, PCDDs and PCDFs

“…The concentration of each PCN congener was expressed as a fraction of the corresponding homolog concentration. This normalization permitted a clear comparison of congener profiles in corresponding homologs (Liu et al 2012a). The profiles of PCN congeners relative to tetraCN, pentaCN, hexaand hepta-CN homologs are shown in Fig.…”

“…Industrial thermal sources including waste combustion and metal smelting were considered important sources of uPOPs (Hu et al 2013b;Liu et al 2012aLiu et al , b, 2014Falandysz 1998). Unintentional atmospheric emissions from anthropogenic sources have might become much more important sources of PCNs in air than before since the moratorium on manufacture and use of PCNs and PCBs in most countries (Liu et al 2012b(Liu et al , 2014Yamashita et al 2003).…”