Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, College of Environmental Science and Engineering, South China University of Technology, Guangzhou 510006, PR China.
Sci Total Environ. 2014 Jan 1;466-467:598-603. doi: 10.1016/j.scitotenv.2013.07.074. Epub 2013 Aug 15.
Besides the Waelz process, the submerged arc furnace (SAF) process has also been extensively used to retain metals from ashes and scraps in the metallurgical industry. However, very little is known about the formation and depletion of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from this thermal process. In this study, an electric arc furnace (EAF) dust treatment plant adopting the SAF process was investigated and compared to the plant adopting the Waelz process. The predominant contributor of PCDD/F I-TEQ input was the EAF dusts, accounting for 98.4% of the total. The PCDD/F contents in the generated fly ashes of the SAF were extremely low, as almost all the organic compounds for PCDD/F formation were decomposed by the high operating temperatures (1500-1700 °C) of the SAF. Therefore, the PCDD/F emission factor of the SAF process (46.9 μg I-TEQ/tonne-EAF dust) was significantly lower than that of the Waelz process (840-1120 μg I-TEQ/tonne-EAF dust). Its PCDD/F output/input ratios (0.23 and 0.50 based on mass and toxicity) were also lower than those of the Waelz process plant (0.62 and 1.19). Therefore, the SAF process is superior to the Waelz process in reducing the potential of PCDD/F formation.
除了韦尔兹法，埋弧炉（SAF）工艺也被广泛用于冶金行业从灰烬和废料中回收金属。然而，对于这个热过程中多氯二苯并对二恶英和呋喃（PCDD/Fs）的形成和消耗，人们知之甚少。在这项研究中，采用 SAF 工艺的电弧炉（EAF）粉尘处理厂与采用韦尔兹法的工厂进行了调查和比较。PCDD/F 总毒性等效输入的主要贡献者是 EAF 粉尘，占总量的 98.4%。SAF 生成的飞灰中 PCDD/F 的含量极低，因为几乎所有用于 PCDD/F 形成的有机化合物都被 SAF 的高操作温度（1500-1700°C）分解了。因此，SAF 工艺（46.9μg I-TEQ/吨 EAF 粉尘）的 PCDD/F 排放因子明显低于韦尔兹法（840-1120μg I-TEQ/吨 EAF 粉尘）。其 PCDD/F 输出/输入比（基于质量和毒性分别为 0.23 和 0.50）也低于韦尔兹法工厂（0.62 和 1.19）。因此，SAF 工艺在减少 PCDD/F 形成潜力方面优于韦尔兹法。
