燃煤电厂周边大气重金属污染特征及来源解析

为探究燃煤电厂周边大气环境中重金属的污染特征与来源,对广东某山区燃煤电厂周边地区环境和污染源的重金属进行测定,分析其污染特征,采用因子分析法和Pb同位素示踪法对环境中的重金属进行来源解析。结果表明,研究区域室内积尘中重金属浓度水平明显高于土壤重金属,污染空间分布与当地气象条件相关。环境空气TSP中重金属主要来自2个污染源,Cd、Pb、As主要来自电厂燃煤,Ca、Mn、Al、Mg主要来自土壤扬尘。TSP、降尘、积尘样品所含的Pb均与电厂采集的煤、炉渣、粉煤灰样品所含的Pb具有同源性,与其他污染源同源性不明显,说明研究区域大气中Pb污染主要来自电厂燃烧所排放的烟尘,其他污染源影响不大。

Pollution Characteristics and Source Apportionment of Heavy Metals in Atmosphere Surrounding a Coal-fired Power Plant

In order to evaluate the pollution characteristics and sources of heavy metals in atmosphere surrounding coal-fired power plant, the concentrations of heavy metals in the environment and sources surrounding a coal-fired power plant were measured in a mountainous area of Guangdong Province. The characteristics of heavy metal pollution were also studied. The source apportionment of heavy metals in local environment was carried out using factor analysis and lead (Pb) isotope analysis technique. The results showed that heavy metal concentration in indoor dusts of study area was significantly higher than in soil, which spatial distribution of pollution associated with the local meteorological conditions. The pollution of heavy metals in the ambient air TSP was mainly from two sources. Cd, Pb, As were mainly from coal-fired power plants, and Cu, Mn, Al, Mg were mainly from soil dust. Pb isotope in samples of TSP, deposits and dusts was homologous with samples of coal, slag and fly ash from the power plant, but not with other sources. Thus, atmospheric Pb pollution in study area was mainly from the power plant emissions of soot, not other sources of pollution.