污水氯和二氧化氯消毒过程中溶解性有机物变化的三维荧光光谱解析

采用三维荧光光谱（3DEEM）技术对污水在氯和二氧化氯消毒过程中溶解性有机物（DOM）的变化进行了初步解析.结果表明,与饮用水、地表水等不同,生物处理出水含有较多的芳香族蛋白质和溶解性微生物代谢产物,且其中的腐殖质主要为生物源,芳香性较弱.在氯和二氧化氯消毒后,污水DOM中的芳香族蛋白质和微生物代谢产物类物质的荧光峰发生蓝移,即峰值的激发或发射波长减少了几个nm,这可能由芳香环结构的破坏引起;而腐殖质类物质的荧光峰发生红移,即峰值的激发或发射波长增加了几个到二十几个nm,此现象与地表水相反,可能与腐殖质的来源不同有关.与遗传毒性的变化类似,氨氮对水样氯消毒后的荧光变化有明显影响,但对二氧化氯消毒后的荧光变化无明显影响.

Characterization of the Change in DOM During Wastewater Chlorine and Chlorine Dioxide Disinfections by 3DEEM

The change of DOM (dissolve organic matter) during wastewater chlorine and chlorine dioxide disinfections was characterized by 3DEEM (three-dimensional excitation emission matrix fluorescence spectroscopy) method. The results showed that the DOM in wastewater tested was quite different from drinking water and surface waters. It contained more aromatic proteins and soluble microbial products, and the humus were predominately microbially derived and had less aromatic moieties. After chlorine and chlorine dioxide disinfections, the excitation or emission wavelength of EEM (excitation emission matrix) peaks for aromatic proteins and soluble microbial products shifted to longer wavelength by several nanometers, which was probably caused by the decomposition of aromatic structure; while the excitation or emission wavelength of EEM peaks for humus shifted to shorter wavelength by several to more than twenty nanometers, which was different from surface waters, and this phenomenon was considered to be caused by their different resources. Similar to the change in genotoxicity, ammonia nitrogen significantly influenced the change in EEM during chlorine disinfection, but not during chlorine dioxide disinfection.