猪场沼液处理过程中溶解性有机质的光谱学特征

猪场沼液无序排放会导致严重的水环境问题,探索猪场沼液处理过程中有机物变化的检测方法,可以为养殖废水处理和排放管控提供技术支撑。利用三维荧光光谱法和紫外-可见分光光度法对猪场沼液处理过程中溶解性有机物(DOM)的光学参数进行分析。结果表明:猪场沼液DOM的三维荧光图谱显示其主要存在类腐殖质、类色氨酸和类酪氨酸3类物质,以类腐殖质物质为主;经AO处理后猪场沼液中的类色氨酸物质部分转化为类酪氨酸物质;经序批式生物膜反应器(SBBR,由SBBR1和SBBR2组成)工艺处理后,类色氨物质全部被分解转化。猪场沼液经SBBR2和氧化塘处理后,DOM浓度和各荧光组分含量有所升高,需要进一步调试优化。DOM在254nm处的光吸收系数(A254)、各特征荧光峰强度以及特征荧光峰总强度与TN、溶解性有机碳(DOC)均具有显著正相关性,因此利用猪场沼液DOM的光谱学特征,不仅可以指示废水中DOM成分的转化状况,也可作为判断工艺流程处理效果的依据,还能较好地表征TN和DOC,具有广泛的应用前景。

Spectral characteristics of dissolved organic matter during process of biogas slurry from swine farm

The disorder emission of biogas slurry from swine farms will lead to serious problems of water environment.To explore the detection method of the change of organic matters during the treatment process of biogas slurry can provide the technical support for the treatment of swine wastewater and the emission control and management.Through three-dimensional fluorescence spectrum and ultraviolet-visible spectrum,the characteristics of dissolved organic matter(DOM)during the treatment process of biogas slurry were studied.The results showed that,there were three main fluorescent matters in DOM,which contained humic-like,tryptophan-like and tyrosine-like matters.Among them,the humic-like substances were the main component.After AO treatment,the tryptophan-like matters in biogas slurry were partly transformed into tyrosine-like substances,and after sequencing batch biofilm reactor(SBBR,containing SBBR1 and SBBR2),the tryptophan-like substances were almost totally decomposed.The spectral parameters showed that the concentrations of DOM and fluorescent components of all components increased rather than decreased after the treatment of SBBR2 and oxidation pond,which suggested that these reactors needed to further debug.The optical parameters of DOM including the absorption coefficients at wavelength 254 nm(A254),the intensities of individual fluorescent components and the total fluorescent intensities all positve correlated significantly to TN and dissolved organic carbon(DOC)concentrations.Therefore,the spectral characteristics of DOM not only could indicate the DOM transformation in biogas slurry from swine farm,but also could be applied to judge the processing effect and could be further to characterize the TN and DOC.All these suggested that it had a wide application prospect.