内源呼吸过程溶解性代谢产物的光谱特性分析

Spectral Characteristics of Soluble Metabolites During Endogenous Respiration

微生物内源呼吸期对污水处理过程具有重要意义.为了更清晰地了解微生物内源呼吸过程,采用三维荧光光谱、紫外光谱结合呼吸图谱对微生物内源呼吸过程进行解析.结果表明,三维荧光光谱和紫外光谱在内源呼吸各个阶段有明显的不同:1内源呼吸快速下降期(第1 d):腐殖酸峰的激发波长(Ex)和发射波长(Em)分别出现5 nm、6 nm的蓝移,荧光指数f450/500和HIX(humification index)分别减小了9.3%、0.2%,UV253/203和UV254分别增加了37.5%、200%,预示着混合液中可生物降解有机物的存在;2内源呼吸慢速下降期(第2 d):f450/500增加了0.5%,HIX减小0.2%,UV253/203减小了20%,UV254增加了16.7%,预示着细胞可能出现了水解或自溶;3内源呼吸稳定期(第3~5 d):腐殖酸峰基本保持不变预示了微生物适应了饥饿环境.本研究从代谢产物的角度解析了内源呼吸过程,为污水处理过程控制提供了新的思路.

Endogenous respiration phase plays an important role in the sewage treatment process. In order to clearly understand the endogenous respiration process of the activated sludge process,three-dimensional fluorescence spectroscopy,ultraviolet spectroscopy and respirogram were employed for the analysis of endogenous respiration process. Results showed that the three-dimensional fluorescence spectroscopy and UV spectroscopy could identify all stages significantly. The following conclusions could be drawn: 1Rapid decline phase of endogenous respiration: the excitation wavelength( Ex) and emission wavelength( Em) of humic peak showed blue shift of 5 nm and 6 nm,respectively,the fluorescence index f450 /500 and HIX( humification index) were reduced by 9. 3% and0. 2%,respectively,UV253 /203 and UV254increased by 37. 5% and 200%,respectively. These results indicated the presence of bioavailable organics; 2Slow decline phase of endogenous respiration: f450 /500 was increased by 0. 5%,HIX was reduced by 0. 2%,UV253 /203 was reduced by 20%,UV254 was increased by 16. 7%. These results indicated that hydrolysis or autolysis of cells might occur; 3Stable phase of endogenous respiration: humic acid peak remained unchanged,indicating the adaption of microorganisms to starving environment. The analysis of the endogenous respiration process from the perspective of metabolites provides a new way for control of microbial wastewater treatment process.