State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China.
School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210023, China.
Bioresour Technol. 2022 Sep;360:127580. doi: 10.1016/j.biortech.2022.127580. Epub 2022 Jul 4.
The advanced nitrogen removal under low temperature is inhibited because of reduction of the microbial activity. Packed bed reactors filled with different magnetic carriers (0, 0.3, 0.6, 0.9 mT) were constructed to enhance advanced denitrification under low temperature (5 ℃). Results showed that 0.3 and 0.9 mT carriers significantly improved denitrification, indicating the "window" effect. Total nitrogen removals were increased by 6.96% and 8.25%, and NO accumulation decreased by 25.70% and 13.90% in 0.3 and 0.9 mT reactors, respectively. Analysis of enzyme activity and electron transport chain showed that 0.3 mT carrier mainly increased NIR activity by improving compound III and cytC abundance while 0.9 mT carrier mainly increased NAR activity by improving compound I and NADH abundance, indicating different pathways. Similar microbial community in 0.3 and 0.9 mT reactors were revealed. Overall, weak magnetic carriers can be used to enhance advanced nitrogen removal under low temperature.
低温下的高级脱氮受到抑制,因为微生物活性降低。构建了填充不同磁性载体(0、0.3、0.6、0.9 mT)的填充床反应器,以增强低温(5℃)下的高级脱氮。结果表明,0.3 和 0.9 mT 载体显著提高了脱氮效果,表明存在“窗口”效应。0.3 和 0.9 mT 反应器中的总氮去除率分别提高了 6.96%和 8.25%,NO 积累分别降低了 25.70%和 13.90%。酶活性和电子传递链分析表明,0.3 mT 载体主要通过提高复合物 III 和 cytC 丰度来增加 NIR 活性,而 0.9 mT 载体主要通过提高复合物 I 和 NADH 丰度来增加 NAR 活性,表明存在不同的途径。0.3 和 0.9 mT 反应器中存在相似的微生物群落。总体而言,弱磁性载体可用于增强低温下的高级氮去除。