黄土絮凝剂对沙湖水质净化及溶解性有机质的去除

EFFECT OF LOESS FLOCCULANT ON WATER PURIFICATION AND DISSOLVED ORGANIC MATTER REMOVAL IN SHAHU LAKE

采用沙湖黄土作为絮凝剂,以硅藻土为参照,探究沙湖黄土对沙湖中水质絮凝净化效果。同时采用同步荧光光谱结合导数荧光、平行因子分析和二维相关光谱分析沙湖黄土对沙湖溶解性有机物(DOM)的净化效果。结果表明:黄土对TN、TP、COD_(Mn)和Chl.a的最高去除效率分别为28.85%、51.52%、24.87%和42.86%。100目和200目沙湖黄土对TP和TN均具有较好的絮凝效果,而硅藻土仅TN的絮凝效果优于黄土。DOM的平行因子分析(PARAFAC)能够识别5个荧光组分,类蛋白荧光为主要的荧光组分。黄土絮凝剂对类蛋白荧光组分(C5)去除效果最高,为56.38%。二阶导数荧光能够识别出6个荧光峰,类蛋白、类富里酸和类腐植酸物质的去除率分别为48.54%、16.45%和1.43%。二维相关光谱分析结果表明,黄土絮凝剂对荧光有机物的去除次序为285 nm→336 nm→369 nm,类蛋白荧光物质能够优先被去除。因此,沙湖黄土可作为絮凝剂用于净化沙湖水质。

In this study,the loess in Shahu Lake was used as a flocculant to explore the water purification effect of flocculation,with diatomite used as a control group.Meanwhile,the purification effect of loess on dissolved organic matter(DOM)in Shahu Lake water was analyzed by synchronous fluorescence spectroscopy in combination with derivative fluorescence,parallel factor analysis and two-dimensional correlation spectroscopy.The results showed that the highest removal rates of TN,TP,COD_(Mn)and Chl.a were 28.85%,51.52%,24.87%and 42.86%,respectively.Shahu loess with grain sizes of 100,200 mesh had a better flocculation effect on TP and TN.However,the flocculation effect of diatomite on TN was better than that of the loess.Five fluorescent components were identified in DOM parallel factor analysis(PARAFAC),among which the protein-like component was the dominant one.The loess flocculant had the highest removal effect(56.38%)on the protein-like fluorescent component(C5).The second derivative fluorescence could identify six fluorescence peaks.Among them,the removal rates of protein-,fulvic-and humic-like substances were 48.54%,16.45%and 1.43%,respectively.The results of the two-dimensional correlation spectroscopy analysis showed that the preferential sequence of removal of the fluorescent components by loess flocculant followed the order of 285 nm→336 nm→369 nm,suggesting that protein-like fluorescent component was removed preferentially.Shahu loess can be used as a flocculant to purify Shahu Lake water.