Micro- and nanochemistry of fly ash from a coal-fired power plant
Micro- and nanochemistry of fly ash from a coal-fired power plant
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DOI：
10.2138/am-2003-11-1228
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发表时间：
2003-11-01
影响因子：
3.1
通讯作者：
Lumpkin, GR
中科院分区：
文献类型：
--
作者：
Gieré, R;Carleton, LE;Lumpkin, GR
对燃煤电厂飞灰进行了调查，以获得有关其物理和化学性质的详细信息，并了解其在垃圾填埋场处置可能对环境和健康造成的影响。所研究的材料是通过燃烧伊利诺伊州盆地的煤炭产生的，并通过静电除尘器被困在发电厂内。它是一种细粒、低钙的飞灰，主要含有二氧化硅、三氧化二铝和三氧化二铁，并富含许多有毒元素(如Be)。锌、砷、镉、铊、铅和铀)是煤的30倍。火山灰主要由赤铁矿、磁铁矿、莫来石、石英和无定形物质组成。这些组分主要以直径小于13微米的球形颗粒形式存在。通过扫描、透射电子显微镜和电子探针显微分析，研究了单个飞灰颗粒的物理、化学和结构特征。结果表明，除了复杂的聚球体外，单个粒子在化学上是相当均匀的，但具有相似物理和结构属性的粒子之间存在着显著的组成差异。电子探针数据证明，包括铀在内的几种痕量元素被分割成富铁颗粒。透射电子显微镜显示，不同类型的小(
Fly ash from a coal-fired power plant was investigated to obtain detailed information on its physical and chemical properties, and to gain an understanding of potential environmental and health impacts associated with its disposal in landfills. The studied material was produced through combustion of Illinois Basin coal and trapped within the power plant by an electrostatic precipitator. It is a fine-grained, low-Ca fly ash containing primarily SiO2, Al2O3, and Fe2O3, and is enriched in many toxic elements (e.g., Be. Zn, As, Cd, Tl, Pb, and U) by a factor of up to 30 relative to coal. The ash consists of mainly hematite, magnetite, mullite, quartz, and amorphous material. These constituents occur mostly as spherical particles with diameters of less than 13 mum. We examined the physical, chemical, and structural characteristics of individual fly ash particles by scanning and transmission electron microscopy and electron probe microanalysis. The results demonstrate that, with the exception of complex plerospheres, individual particles are chemically fairly homogeneous, but a pronounced compositional variation exists among particles with similar physical and structural attributes. Electron microprobe data document that several trace elements, including U, are partitioned into the Fe-rich particles. Transmission electron microscopy revealed that various types of small (