Operational efficiencies of combined anaerobic baffled reactor and corridor constructed wetland system for domestic wastewater treatment

The operational efficiencies of combined system with anaerobic baffled reactor and corridor constructed wetland (CABR-CCW) for domestic wastewater treatment，including CODCr removal, ammonia removal, phosphorus removal and the role of the plants, were analyzed in this paper. The results revealed that the average removal rates of CODCr and ammonia (NH3-N) of CABR-CCW were 78.9% and 88.55%, respectively, in summer and autumn with HRT (hydraulic retention time) of about 50 hours. However, the average removal rate of CODCr was 56.6%, and that of NH3-N remained above 47%, without changing the daily treatment capacity. The removal rate of phosphorus remained above 83.6%, and 92.3% in summer as a result of the absorption of the plants in CCW due to the use of special substrate such as cinder and shale. So the removal of phosphorus mostly attributed to the adsorption of substrate of CCW. The adsorption capability of substrate did not reach saturation, but the data showed a downtrend. The effect of the plants in CCW is remarkable to NH3-N removal, but unremarkable to phosphorus removal.