Cortez R, Zaghloul H H, Stephenson L D, Smith E D, Wood J W, Cahil D G
a U.S. Army Construction Engineering Research Laboratories , Champaign , Illinois.
b University of Illinois , Urbana , Illinois.
J Air Waste Manag Assoc. 1996 Nov;46(11):1075-1080. doi: 10.1080/10473289.1996.10467543.
Plasma processing has been identified as a useful tool for immobilizing heavy metal-contaminated wastes into safe, leach-resistant slag. Although much effort has gone into developing this technology on a pilot scale, not much information has been published on basic research topics. A laboratory-scale plasma arc furnace located at the University of Illinois was operated in cooperation with the U.S. Army Construction Engineering Research Laboratories in an effort to establish an understanding of the chemical and physical processes (such as metal volatilization and resultant gas evolution) that occur during thermal plasma treatment of metal-spiked samples. Experiments were conducted on nickel and chromium using a highly instrumented furnace equipped with a 75 kW transferred arc plasma torch. The volatility of nickel and chromium was examined as a function of varying oxygen partial pressures. Oxidizing conditions reduced the total dust gathered for both the nickel and chromium samples, although each dust sample was found to be metal-enriched. Plasma treating increased the leach-resistance of the slags by at least one order of magnitude when compared to unprocessed specimens. The leach- resistance of the nickel-containing slags increased in the presence of oxygen, whereas chromium samples remained relatively constant.
等离子体处理已被视为一种将重金属污染废物固化为安全、抗浸出炉渣的有用工具。尽管在中试规模上开发这项技术已付出诸多努力，但关于基础研究课题的信息公布得并不多。伊利诺伊大学的一台实验室规模的等离子体电弧炉与美国陆军工程兵团建筑工程研究实验室合作运行，旨在深入了解在热等离子体处理加标金属样品过程中发生的化学和物理过程（如金属挥发及由此产生的气体逸出）。使用配备75千瓦转移弧等离子体炬的高度仪器化熔炉对镍和铬进行了实验。研究了镍和铬的挥发性随氧分压变化的情况。氧化条件减少了镍和铬样品收集到的总粉尘量，不过每个粉尘样品都富含金属。与未处理的样品相比，等离子体处理使炉渣的抗浸出性提高了至少一个数量级。含镍炉渣在有氧存在时抗浸出性增强，而铬样品则保持相对稳定。
