发酵制药废水二级出水中溶解性有机物特性分析

The dissolved organic matter (DOM) in the secondary effluent from fermentation pharmaceutical wastewater is a key limiting factor for wastewater reclamation and reuse. An in-depth analysis of the characteristics of DOM will help to optimize the process operation to effectively remove DOM from wastewater. In this study, secondary effluents from five kinds of fermentation pharmaceutical wastewaters including amino acids, cephalosporins, antibiotics, vitamins and abamectin, were collected to investigate the characteristics of DOM. The characteristics of DOM in secondary effluent were analyzed using XAD-8 resin, high performance liquid chromatography-size exclusion chromatography, fourier transform infrared spectroscopy and fluorescence excitation-emission matrix spectroscopy. The results showed that, the secondary effluents of fermentation pharmaceutical wastewaters exhibited high salinity and color. The concentration of organic matters in the secondary effluent were about (48.6~232.2 mg•L^-1). The hydrophobic fraction was the dominant composition of DOM with the molecular weight distributed widely (210~10000 Da) in secondary effluent. DOM in secondary effluent contained a large number of unsaturated double bonds and benzene ring structures, as well as chromophore and auxiliary groups such as -OH, -NH₂, and C〖FY=, 1〗O, resulting in strong color of wastewater. Three humic-like substances (C1, C3 and C4) and one protein-like substance (C2) were found by EEM-PARAFAC analysis. The humic-like substances (C1 and C3) were the largest group of DOM in the secondary effluent of fermentation pharmaceutical wastewater. The comprehensive identification of DOM composition would contribute to optimize the pharmaceutical wastewater treatment process.