Department of Geological Sciences, University of Texas at El Paso, El Paso, Texas 79968, United States.
Environ Sci Technol. 2010 Dec 1;44(23):9219-24. doi: 10.1021/es102439g. Epub 2010 Nov 3.
Atmospheric Zn emissions from the burning of coal and tire-derived fuel (TDF) for power generation can be considerable. In an effort to lay the foundation for tracking these contributions, we evaluated the Zn isotopes of coal, a mixture of 95 wt % coal + 5 wt % TDF, and the particulate matter (PM) derived from their combustion in a power-generating plant. The average Zn concentrations and δ(66)Zn were 36 mg/kg and 183 mg/kg and +0.24‰ and +0.13‰ for the coal and coal + TDF, respectively. The δ(66)Zn of the PM sequestered in the cyclone-type mechanical separator was the lightest measured, -0.48‰ for coal and -0.81‰ for coal+TDF. The δ(66)Zn of the PM from the electrostatic precipitator showed a slight enrichment in the heavier Zn isotopes relative to the starting material. PM collected from the stack had the heaviest δ(66)Zn in the system, +0.63‰ and +0.50‰ for the coal and coal + TDF, respectively. Initial fractionation during the generation of a Zn-rich vapor is followed by temperature-dependent fractionation as Zn condenses onto the PM. The isotopic changes of the two fuel types are similar, suggesting that their inherent chemical differences have only a secondary impact on the isotopic fractionation process.
煤和轮胎衍生燃料（TDF）燃烧产生的大气锌排放可能相当可观。为了为追踪这些贡献奠定基础，我们评估了煤、煤和 TDF 混合物以及从火力发电厂燃烧中产生的颗粒物（PM）中的 Zn 同位素。煤和煤+TDF 的平均 Zn 浓度和 δ(66)Zn 分别为 36mg/kg 和 183mg/kg，+0.24‰和+0.13‰。旋风式机械分离器中捕获的 PM 中的 δ(66)Zn 是测量到的最轻的，分别为-0.48‰和-0.81‰。静电除尘器中 PM 的 δ(66)Zn 相对于起始材料略微富集了较重的 Zn 同位素。烟囱中收集的 PM 的 δ(66)Zn 在该系统中最重，分别为+0.63‰和+0.50‰。富锌蒸气生成过程中的初始分馏，随后随着 Zn 冷凝到 PM 上，温度依赖性分馏。两种燃料类型的同位素变化相似，表明它们固有的化学差异对同位素分馏过程只有次要影响。
