高碳氮废水处理中有机物的荧光光谱特征分析

Analysis of Fluorescent Properties of Organic Matter in High CarbonNitrogen Wastewater

采用三维荧光光谱技术考察某厂高碳氮废水中有机物的荧光光谱特征及荧光强度与COD去除效果和氨氮浓度变化的关系。反应器稳定运行后进出水COD分别为5 500和1 510mg/L,对COD的去除率达到72.5%,氨氮浓度增加了40.6%,总氮浓度基本保持不变。通过荧光光谱分析,废水中的有机物主要由类蛋白质和类腐殖酸组成,荧光峰中心位置分别为Ex/Em=275/355 nm和Ex/Em=330/425 nm;蛋白质荧光强度从4 175减少至1 318,其与周期内COD去除率、氨氮浓度均存在较好的线性相关性,R2分别为0.943和0.965。说明可以通过荧光光谱技术定性表征生物处理废水过程中有机物的转化情况及其与碳、氮变化的关系。

The fluorescent properties of organic matter in the high carbon-nitrogen wastewater weredetermined by excitation-emission matrix spectroscopy （EEMs）, and its relationship with COD removal efficiency and change of ammonia nitrogen concentration were investigated. The results showed that when the anaerobic bioreactor was in a stable operating condition, COD concentrations in the influent andeffluent were 5 500 mg/L and 1 510 mg/L respectively, and the removal rate of COD was 72.5%. The concentration of ammonia nitrogen increased by 40.6% , while the total nitrogen concentration almost re- mained unchanged. Fluorescence spectra showed that one humic-like component （Ex/Em = 330/425 nm） and one protein-like component （Ex/Em = 275/355 nm） were identified. The fluorescence intensity of protein reduced from 4 175 to 1 318, and it had a linear correlation with COD removal efficiency and ammonia nitrogen concentration, with R^2 being 0. 943 and 0.965, respectively. This study demonstrated that EEMs could distinguish the transformation characteristics of organic matter and its relationship with carbon and nitrogen content in the process of wastewater treatment.