通过实验室模拟矿化生活垃圾淋滤液对地下水的污染,分析受污染地下水的三维荧光光谱特征,并利 用FRI法 (fluorescence regional integration)研究相应的三维荧光光谱组分特征信息,为建立基 于光学表征技术的地下水污染监测应用提供理论基础。研究结果如下:淋滤液的三维荧光光谱图中 的荧光中心位于Ex /Em =340 nm/420 nm,属于可见区类富里酸物质;而地下水有 两个明显的荧光中心分别位于Ex /Em =280 nm/342 nm附近和Ex /Em =240 nm/446 nm附 近,分别属于类色氨酸物质和紫外区类富里酸物质。随着淋滤液污染程度的增加,可见区类富里酸 的荧光强度增强,类蛋白物质的荧光强度明显减弱; Ⅲ区(富里酸)的Pi,n值无明显变化趋 势,而Ⅵ区(腐殖酸)的Pi,n值呈现递增趋势。因此,认为通过Ex /Em =340 nm/420 nm附 近和Ex /Em =280 nm/342 nm附近的荧光强度比值以及FRI法分区得到的Ⅲ区和Ⅵ区FRI和值的 变化可检测出淋滤液对地下水的污染程度。

Leachates were obtained for mineralized domestic waste of two different landfill ages with the laboratory leaching device. With the simulation experiment for groundwater pollution by landfill leachates, 3-dimensional excitation emission matrix(3DEEM) fluorescence spectra of the groundwater samples which were polluted to different extent were analyzed, all these components in DOM were analyzed using fluorescence region integration (FRI) method, in order to screen the characteristic pollution marks and provide the probability of groundwater pollution monitoring. The results show that the EEM of leachate is characterized by a typical fluorescence chromophore loacted at Ex /Em =280 nm/342 nm and Ex /Em =340 nm/420 nm nearby, dominated by kind of fulvic acid of visible range; and the EEMs of groundwater were characterized by two typical fluorescence chromophores loacted at Ex /Em =280 nm/342 nm and Ex /Em =240 nm/446 nm nearby, dominated by kind of protein-like substrance and fulvic acid of ultraviolet range. With the increase in the proportion of leachate, the fluorescence intensity of fulvic acid in visible range (Ex /Em =310 nm/408 nm nearby) increase, and the fluorescence intensity of protein-like substrance decrease. The groundwater pollution of leachate can be detected by analyzing the change of fluorescence intensity in fulvic acid of visible range, fluorescence intensity ratio of Ex /Em =340 nm/420 nm and Ex /Em =280 nm/342 nm or the FRI of Ⅲ region and Ⅵ region.