LIJiao,GONGBen-zhou,ZHANGYing,et al.Performance of Two-stage Constructed Wetland for Advanced Nitrogen and Phosphorus Removal from Wastewater Treatment Plant Effluent[J].China Water & Wastewater,2023,39(11):75-81.
Performance of Two-stage Constructed Wetland for Advanced Nitrogen and Phosphorus Removal from Wastewater Treatment Plant Effluent
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第39卷
Number:
第11期
Page:
75-81
Column:
Date of publication:
2023-06-01
- Keywords:
- constructed wetland; effluent from wastewater treatment plant; nitrogen and phosphorus removal; electrolysis; microalgae
- Abstract:
- In view of the shortage of carbon sources for denitrification and low phosphorus removal efficiency of constructed wetland for advanced treatment of effluent from the existing wastewater treatment plants, this paper established a pilot system with scale of 100 m3/d consisting of first-stage constructed wetland coupled with electrolysis and second-stage constructed wetland coupled with microalgae packing with lightweight media for advanced phosphorus and nitrogen removal from wastewater treatment plant, and investigated the effects of voltage and hydraulic load on phosphorus and nitrogen removal efficiency of the system. Voltage and hydraulic load had significant effects on the nitrogen removal efficiency of the system, but had no significant effects on the phosphorus removal efficiency. When the temperature, voltage, hydraulic load and BOD5/TN ratio were （20±4） ℃, 15 V, 0.35 m3/(m2·d) and 0.3-0.4, respectively, the NH4+-N, TN and PO43--P in effluent were 0.93 mg/L, 1.50 mg/L and 0.04 mg/L, respectively, and their removal rates were 65.17%, 87.91% and 93.65%, respectively, which met the class Ⅳ limit specified in surface water quality standard. Among them, the removal rates of NH4+-N, TN and PO43--P in the first-stage constructed wetland were 25.47%, 63.17% and 79.37%, respectively, while those in the second-stage constructed wetland were 39.70%, 24.74% and 14.28%, respectively. The first-stage constructed wetland coupled with electrolytic system played a major role in nitrogen and phosphorus removal, and the dominant denitrifying functional bacteria were Arenimonas, Hyphomicrobium, Rivibacter, Hydrogenophaga and Thauera.
Last Update:
2023-06-01