RETRACTED: Research on the Effect of Sewage Concentration on Treatment Efficiency of Constructed Wetlands
Authors: Ling Zhen , Yang Ju Rui , Lu Zhe Nai 
Published: October 2011

Retracted article: By changing the surface flow(SF) and subsurface flow (SSF)constructed wetlands inflow water total nitrogen (TN) concentrations, with 6 plant species (purple leaf canna, water onion, water hyacinth, water celery, calamus, reed) in comparative experiments, comparative analysis of the 6 different SF and SSF constructed wetlands treatment rate with the variation of the concentration obtained in the 6 different plant SF and SSF constructed wetlands, the optimal concentration theory, theory of optimal removal rate, the actual optimal concentration, the actual optimal removal rate and TN maximum daily processing load. The results showed that: in the 6 different plant of SF and SSF constructed wetlands for TN removal efficiency decreased as the concentration increased, different plant, different levels of treatment rate reduction, and removal value of SSF was lower than SF. Purple leaf canna removal reduced the minimum, SF processing rate decreased 17.07%, SSF dropped 15.94%; Reed removal rate decreased obviously, the SF processing rate decreased 20.86%, SSF dropped 18.2%. Meanwhile, according to the result of the experiment, the maximum TN daily remove quantity in the six species of plants of SF constructed wetland was 547.20 g•m-2•d-1;in SSF constructed wetland was 577.60 g•m-2•d-1. Wetland as an efficient, low consumption of new sewage treatment technology has been widely accepted, especially in total nitrogen (TN) in the application phase for the people attention. Study found that of nitrogen removal efficiency of constructed wetlands and external factors, a wetland substrate, plant species, microbes, sewage load, residence time, nitrogen in sewage and water distribution methods[1]. For the wastewater load on the removal of wetlands, Zhou Yaohua so that low concentration of domestic sewage (20% water) on the ground flora as a whole more effective than a higher concentration of the decontamination wastewater (100% effluent) better overall removal [2]. Cui Fang water residence time in the study of the impact of decontamination capability of wetlands that the reed wetland water CODcr, TP, NH3-N concentration had little effect on the removal, and TN concentrations had a significant effect on the removal, removal of only 27% [3], Yuan Donghai and others that wetlands on the initial concentration of pollutants in wastewater have certain requirements, low pollution case, the constructed wetland was better; higher concentration of pollutants cases, the purification efficiency dropped [4]. Effluent decontamination effect on the wetland will have some impact, at present, domestic and international research to a single species of plants, mainly a single type of wetland, considering the different plants, different types of comparative study of wetlands was less. By changing SF and SSF constructed wetlands, inflow water TN concentrations, with 6 plant speciesin comparative experiments, comparative analysis of the 6 different plants of SF and SSF constructed wetlands treatment rate with the variation of the concentration obtained in 6 different plant SF and SSF constructed wetlands, the optimal concentration theory, theory of optimal removal rate, the actual optimal concentration, optimal removal rate and the actual TN maximum daily processing load, optimizing the hydraulic conditions of wetlands. Research on the promotion of artificial wetland technology, further development of eco-environmental rehabilitation has a certain significance