LIJia,SHISu-jie,ZHOUZhi-ming,et al.Performance and Microbial Action of Intermittent Aeration-Backwashing Constructed Wetland[J].China Water & Wastewater,2022,38(19):8-15.
Performance and Microbial Action of Intermittent Aeration-Backwashing Constructed Wetland
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第38卷
Number:
第19期
Page:
8-15
Column:
Date of publication:
2022-10-01
- Abstract:
- A novel intermittent aeration coupled air-water backwashing constructed wetland system (CW1) was constructed, and the performance and microbial action of CW1 and traditional constructed wetlands (CW0) were investigated. The results showed that intermittent aeration maintained the dissolved oxygen in CW1 bed between 0.5 mg/L and 3.5 mg/L, creating an anaerobic/anoxic-aerobic alternating microenvironment, and the average removal efficiencies of COD, NH4+-N, TN and TP by CW1 increased by 7.2%, 13.1%, 8.4% and 6.5% respectively, compared with CW0 during the stable operation period. The combined backwashing with water intensity of 8 L/(m2·s), gas intensity of 6 L/(m2·s) and frequency of 5 min/6 d promoted the recovery of active sites and substrate pore structure, and enhanced the transport capacity of nutrients/metabolites inside and outside the biofilm. Intermittent aeration coupled with water?air backwashing increased the richness and diversity of microbial communities in CW1, and simultaneously enriched anaerobic/anoxic and aerobic functional bacteria such as norank_ f__NS9_marine_group (3.9%), norank_f__Saprospiraceae (3.4%) and norank_f__norank_o__Saccharimonadales (4.1%) at genus level, and the functional genes involved in the processes of carbohydrate metabolism and amino acid metabolism accounted for more than 5% in CW1, accelerating organic matter degradation and nitrogen removal metabolism mediated by these genes.
Last Update:
2022-10-01