[Purification of ammonia-type eutrophic waterbody in surface flow constructed wetland at a low temperature].
Denitrification in three floating-plant systems, including two subspecies of hyacinth and duckweed, and foamy board system were investigated by batch cultivation at a low water temperature of 6.8 degrees C to 7.2 deggres C. Effect of initial COD on the system at a water temperature of 6.4 degrees C to 11.2 degrees C was also discussed. The results were obtained as follows: DO was one of the important factors, NH4+ -N removals in aerobic condition were 61%-88% in overall period. NH4 -N removal in plant systems was higher than that in the foamy board and control systems while differences of TN and COD removals among plant system, foamy board system and control system were determined by the floating-plant type. The increase of initial COD concentration, followed by the decrease of DO from >4 mg/L to 0 mg/L, resulted in an obvious improvement of NO; -N removal. However, it had a less effect on other water quality norms such as COD, TN and NH4+ -N.
Zheng
Shao-kui
SK
State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China.
Zhang
Yan-yan
YY
Yang
Zhi-feng
ZF
Liu
Jia-gang
JG
D001673:Biodegradation, Environmental; D003080:Cold Temperature; D031806:Eichhornia / Q000378:metabolism; D005068:Eutrophication; D010944:Plants / Q000378:metabolism; D000644:Quaternary Ammonium Compounds / Q000302:isolation & purification / Q000378:metabolism*; D014873:Water Pollutants / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*; D053833:Wetlands
D000644:Quaternary Ammonium Compounds; D014873:Water Pollutants