EFFECTS OF INTERMITTENT AERATION UNDER DIFFERENT OPERATION CONDITIONS ON THE POLLUTANT REMOVAL OF A PILOT-SCALE CONSTRUCTED WETLAND

摘要

Application of constructed wetlands (CWs) is one of the most promising treatments of wastewater. Herein, to improve the sewage treatment effect of the CWs, the intermittent aeration is applied as it can potentially enhance the removal efficiencies of COD, TN and TP. A pair of pilot-scale CW systems planted with I. wilsonii and C. alternifolius was aerated intermittently and operated under different hydraulic retention time (HRT), water flow regimes, aeration positions and aeration rates to evaluate the performances of pollutants removal. Results showed that the systems with the up flow regime and the HRT at 4d reached optimal efficiency. Besides, the single unit aeration in the middle part of the system showed better performance than that of the double units aeration. Aeration rate test indicated that the higher gas- water ratio led to the better performance of the pollutants removal.