冬季Z市水源DOM组成、三卤甲烷生成势特性及去除研究

Analysis of DOM composition,the formation potential of trihalomethanes and its removal from water source of Z City in winter

以冬季Z市水源地2条入库河流为研究对象,通过联合运用三维荧光光谱、树脂分离分级和紫外可见分光光度法,探究水源地原水中溶解性有机物(DOM)的荧光成分、来源、组成、腐殖化程度与消毒副产物三卤甲烷(THMs)生成势的关系。结果表明:三维荧光光谱解析出水源地2条入库河流原水中共有类蛋白物质(C1)、紫外腐殖酸类物质(C2)、陆地/人造腐殖质类物质(C3)3个荧光峰;水源地的2条入库河流(Q河与X河)的3个荧光峰峰值分别为4.50、10.75、7.56和1.33、9.24、7.56;荧光源指数(FI)与生物源指数(BIX)均体现出水源地原水中的DOM主要为陆源输入;此外,水源地原水中的DOM化学分级之后,5个组分浓度表现为疏水性有机酸(HoA)>亲水物质(HiM)>疏水中性有机物(HoN)>疏水碱性有机物(HoB)>弱疏水酸性有机物(wHoA);Q河原水氯化后产生CHCl_(3)、CHClBr_(2)和CHBrCl_(2)3种成分,X河氯化后产生CHCl_(3)和CHB_(r)Cl_(2)2种成分,说明河水并没未受到明显的工业污染。水源地2条入库河流原水的DOM各化学分级组分的THMs生成势的研究结果表明,THMs的主要前驱物为HoA和HiM,而HoA、HiM、wHoA 3种组分对THMs的生成能力均较强,与紫外吸收特性SUVA相一致,说明生成THMs的能力也很强,应选取工业聚合氯化铝进行强化混凝去除。

Taking the water source of Z City in winter as the research object,the relationship between the fluorescence composition,source,composition,humification degree of dissolved organic matter(DOM)and the generation potential of trihalomethanes(THMs)was investigated by the combined use of 3D fluorescence spectroscopy,resin separation and classification,and UV-vis spectrophotometry.The results showed that a total of three fluorescence peaks were resolved by 3D fluorescence spectra:protein-like material(C1),ultraviolet humic acid material(C2)and terrestrial/artificial humic material(C3)in the raw water of the water source.The three fluorescence peaks in Q River and X River were 4.50,10.75,7.56 and 1.33,9.24,7.56,respectively.The fluorescence source index(FI)and biogenic index(BIX)both reflected that DOM of the water source was mainly terrestrial source input.In addition,after the chemical classification of DOM of the water source,the concentrations of five components were as follows:hydrophobic organic acids(HoA)>hydrophilic substances(HiM)>hydrophobic neutral organic substances(HoN)>hydrophobic alkaline organic substances(HoB)>weak hydrophobic acidic organic substances(wHoA).CHCl_(3),CHClB_(r)2 and CHBrCl_(2) were produced by chlorination of Q River raw water,and CHCl_(3) and CHBrCl_(2) were produced by chlorination of X River,indicating that the river water was not significantly polluted by industry.At the same time,the study of disinfection by-product THMs generation potential was conducted on each chemically graded component of DOM of the water source,and it was found that the main precursors of THMs were HoA and HiM,and HoA,HiM and wHoA had a strong ability to generate THMs,which was consistent with SUVA values of UV absorption characteristics,indicating that the ability to generate THMs was also strong.The industrial polyaluminium chloride should be selected to enhance coagulation for removal.