JIANG Yu-hao,LI Min,TANG Ming-zhe,et al.Purification of Micro-polluted River Water by Hybrid Process of Gravel Contact Oxidation and Subsurface Flow Constructed Wetland[J].China Water & Wastewater,2021,37(5 5):57-65.
Purification of Micro-polluted River Water by Hybrid Process of Gravel Contact Oxidation and Subsurface Flow Constructed Wetland
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第37卷
Number:
5 5
Page:
57-65
Column:
Date of publication:
2021-03-01
- Keywords:
- gravel contact oxidation; subsurface flow constructed wetland; micro-pollution; HRT; influent distribution ratio
- Abstract:
- Purification effect of micro-polluted river water by a hybrid process of gravel contact oxidation and subsurface flow constructed wetland was investigated. After 26 days of regulation and operation by changing the influent distribution ratio and aeration mode, the hybrid process simulation device was successfully started. The removal efficiencies of COD and NH4+-N in the gravel contact oxidation zone (gravel zone for short) were both stable at about 75%, and the TN removal efficiency was 45%-60%. In order to further enhance the purification efficiency, influences of gravel zone hydraulic retention time (HRT), influent distribution ratio between the gravel aeration zone and nonaeration zone (O/A) on effluent quality of the gravel zone and subsurface flow constructed wetland were discussed. When HRT of gravel zone was 5 h, the gravel zone had a good removal effect on pollutants, in which the average removal efficiencies of COD, NH4+-N, and TN could reach about 72%, 75.28% and 67.79%, respectively. And the removal rates of constructed wetland were 31%, 43% and 28%, respectively. When influent distribution ratio between the aeration zone and non-aeration zone was 1 ∶1, the average removal efficiencies of COD and NH4+-N were higher, which were 77.39% and 84.91%, respectively. When the influent distribution ratio was 1 ∶2, the maximum removal efficiency of TN was obtained, which was 68.5%, and the removal rate of TN in constructed wetland was 24.47%. Consequently, HRT of 5 h was chosen as the optimal parameter, and influent distribution ratio could be flexibly selected according to different water pollution status. The results can provide theoretical support for practical engineering applications.
Last Update:
2021-03-01