Experimental Study of Constructed Wetland Technology in China Northern Area

The test on treating pollution water of Handan by using a two-grade series constructed wetland system.The results show that the constructed wetland has a purifying effect perennial,the removal rate of COD,TN and TP are 25%-65%,29%-94% and 30%-80%.Under the same hydraulic loading,the wetland with relatively better growing plants demonstrated higher pollutants removal efficiency than that with relatively worse growing plants.The removal effect and stability of subsurface flow wetland is better than surface constructed wetland's.The removal effect showed certain seasonal variation,the rate in summer better than in cold winter.