Polychlorinated dibenzo-p-dioxin and dibenzofuran and polychlorinated biphenyl emissions from different smelting stages in secondary copper metallurgy

• Published in: Chemosphere (Oxford) 2013-01, Vol.90 (1), p.89-94
• Main Authors: Hu, Jicheng, Zheng, Minghui, Nie, Zhiqiang, Liu, Wenbin, Liu, Guorui, Zhang, Bing, Xiao, Ke
• Format: Article
• Language: English
• Subjects: Air Pollutants - analysis; Air Pollution - statistics & numerical data; Applied sciences; Atmospheric pollution; Benzofurans - analysis; Copper; dibenzofuran; Dibenzofurans, Polychlorinated; emissions; Environmental Monitoring; Exact sciences and technology; Metallurgy; Other pollution sources in industry; oxidation; PCBs; PCDD/Fs; Pollution; Pollution sources. Measurement results; polychlorinated biphenyls; Polychlorinated Biphenyls - analysis; polychlorinated dibenzodioxins; Polychlorinated Dibenzodioxins - analogs & derivatives; Polychlorinated Dibenzodioxins - analysis; Raw material; raw materials; Secondary copper; Smelting stage
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2012.08.003

► Dioxin emissions from different secondary copper smelting stages were investigated. ► Feeding-fusion was identified as main dioxin emission stage during smelting. ► Raw material composition significantly influenced PCDD/F and PCB discharges. Secondary copper production has received much attention for its high emissions of polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/F) reported in previous studies. These studies focused on the estimation of total PCDD/F and polychlorinated biphenyl (PCB) emissions from secondary copper smelters. However, large variations in PCDD/F and PCB emissions reported in these studies were not analyzed and discussed further. In this study, stack gas samples at different smelting stages (feeding-fusion, oxidation and deoxidization) were collected from four plants to investigate variations in PCDD/F and PCB emissions and characteristics during the secondary copper smelting process. The results indicate that PCDD/F emissions occur mainly at the feeding-fusion stage and these emissions contribute to 54–88% of the total emissions from the secondary copper smelting process. The variation in feed material and operating conditions at different smelting stages leads to the variation in PCDD/F emissions during the secondary copper smelting process. The total PCDD/F and PCB discharge (stack gas emission+fly ash discharge) is consistent with the copper scrap content in the raw material in the secondary copper smelters investigated. On a production basis of 1ton copper, the total PCDD/F and dl-PCB discharge was 102, 24.8 and 5.88μgTEQt−1 for the three plants that contained 100%, 30% and 0% copper scrap in their raw material feed, respectively.