Use low direct current electric field to augment nitrification and structural stability of aerobic granular sludge when treating low COD/NH4-N wastewater

作者：Huang Wenli; Wang Wenlong; Shi Wansheng; Lei Zhongfang; Zhang Zhenya^*; Chen Rongzhi; Zhou Beibei

来源：Bioresource Technology, 2014, 171: 139-144.

DOI：10.1016/j.biortech.2014.08.043

• Aerobic granules
• Electric field
• Nitrification
• Free ammonia
• Extracellular polymeric substances (EPS)

This study explored the effect of low direct current (DC, <= 5 V) electric field on aerobic granules by using two identical square sequencing batch reactors (SBRs) when influent chemical oxygen demand to ammonia nitrogen (COD/NH4-N) ratio decreased from 6 to 1.2 (with COD fixed at 600 mg/L). Results showed that the granules from the electro-augmentation SBR had a more compact and dense microbial structure with enriched Actinobacteria, Bacteroidia, Betaproteobacteria, and Nitrospira. Compared to the control, these granules produced 17.4% and 21.5% more proteins and polysaccharides respectively in the extracellular polymeric substances (EPS), with their integrity coefficient stabilized at 3.3-5.2% during 120 days' operation. Interestingly, more di- and tri-valent metals were accumulated in the electro-augmented granules. In addition, greater than 99% nitrification especially with stably high nitratation efficiency was realized in this new system.

• 出版日期2014-11
• 单位中国科学院大学