Wang Xianbao, Chen Tiantian, Gao Chuyue, Xie Yili, Zhang Anlong
School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi Province 710021, China; China Light Industry Water Pollution Control Engineering Center, Xi'an, Shaanxi Province 710021, China.
School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi Province 710021, China.
Bioresour Technol. 2022 Feb;345:126522. doi: 10.1016/j.biortech.2021.126522. Epub 2021 Dec 9.
Extracellular polymeric substances (EPS) extracted from waste activated sludge were used as endogenous redox mediator to enhance denitrification performance. The nitrate reduction rate increased 1.42-fold when EPS were added at 75 mg C/L (C represents total organic carbon). EPS addition decreased the charge transfer resistance and improved the electron transport system activity. The nitrate reductase and nitrite reductase activities improved by 29.7% and 25.4%, respectively. The activation energy of the system with EPS addition (25.82 kJ/mol) was 31.1% lower than that of the control group (37.49 kJ/mol). Besides, EPS could be used as electron carriers to accelerate electron transport; its primary role was similar to that of the quinone loop in the electron transfer chain. More importantly, EPS addition enhanced carbon source metabolism, which increased the available nicotinamide adenine dinucleotide yield to 1.21 times that of the control group, and thus promoted the denitrification performance of activated sludge.
从废弃活性污泥中提取的胞外聚合物（EPS）被用作内源性氧化还原介质，以提高反硝化性能。当以75mg C/L（C代表总有机碳）添加EPS时，硝酸盐还原率提高了1.42倍。添加EPS降低了电荷转移电阻，提高了电子传输系统活性。硝酸盐还原酶和亚硝酸盐还原酶活性分别提高了29.7%和25.4%。添加EPS的系统的活化能（25.82kJ/mol）比对照组（37.49kJ/mol）低31.1%。此外，EPS可作为电子载体加速电子传输；其主要作用类似于电子传递链中的醌环。更重要的是，添加EPS增强了碳源代谢，使可用烟酰胺腺嘌呤二核苷酸产量提高到对照组的1.21倍，从而促进了活性污泥的反硝化性能。
