Study On The Removal Effect Of Artificial Water Grass On Pollutants Such As Nitrogen And Phosphorus In Polluted Rivers

As one of the most important ecosystems in nature,river ecosystems have significant impact on human production and life since ancient times.But with the human over-exploitation of the river and the continuous discharge of pollutants,river water structure and function has been severely damaged.Therefore,how to effectively control and improve the water quality of polluted rivers is the key to the sustainable development of water resources.As a typical biofilm carrier technology,Artificial Aquatic Plants(AAP)technology has the advantages of low cost,less secondary pollution,quick efficiency of wastewater quality and environmental safety.In this paper,the experiment was carried out by setting AAP biofilm culturing experiment,parameter optimization and microbial community structure analysis experiment and application experiment in wetland.The effects of AAP on sewage treatment were studied and the optimum operating parameters of AAP were determined.So as to provide scientific basis for the application of AAP in polluted water bodies.The artificial film was set for 8 days.The removal rates of COD,NH4+-N and total nitrogen were 63.4%,43.4% and 43.2%,respectively.The dominant species in the artificial aquatic group are Novosphingobium,Hydrogenophaga,Sphingobium,Pedobacter,etc.,which belong to the functional microbes of nitrogen and phosphorus removal.The optimal operating parameters and microbiological information of AAP were clarified.?1 The results showed that the optimum length of artificial water plants was 200 cm,the removal rate of COD,NH4+-N and total nitrogen was 90.07%,82.4%and 42.9%,respectively.Flavobacterium,Methylotenera and Acinetobacter are dominant species,which play an important role in the removal of nitrogen.?2 The removal effect of the best dissolved oxygen concentration range is 3-5mg/L,the removal rate of COD,ammonia nitrogen and total nitrogen of artificial aquatic plants were 88.00%,41.96% and 15.00%,respectively.Flavobacterium and Pseudomonas are dominant species.?3 The best pH value was 8.0-8.5,the removal rate of COD,NH4+-N and total nitrogen were 84.10%,39.42% and 29.67%,respectively.Oxalobacteraceae is the dominant species at pH 5.0-6.0,and the lowest abundance at pH 8.0-8.5.It indicates that Oxalobacteraceae is not the functional bacteria to the removes of nitrogen,phosphorus and COD.?4 The optimum temperature of AAP,s removal effect was summer.The removal rates of COD,NH4+-N,total nitrogen and total phosphorus were 90.02%,59.20%,58.55% and 27.03%,respectively.The Pseudomonas,Azohydromonas and Flavobacterium were the dominant species in this stage of the experiment.The removal efficiency of AAP in Zhaoniu River artificial wetland was studied.The average removal rates of COD,NH4+-N and TN were 38.5%,16.1% and 18.2%,respectively,and the average concentration of DO was increased by 13.9% in 2014.,the average removal rate of COD,NH4+-N and TN increased by 15.7%,2.1% and1.1%in 2015,respectively,and the average concentration of DO increased by11%.Compared with 2015,the average removal rate of COD,NH4+-N and TN increased by8.1%,9.3% and 11.9%,respectively,and the average concentration of DO increased by 21.3%.Artificial aquatic biofilm also detected Flavobacterium,Methylotenera and Acinetobacter,although the relative abundance is not high,but also can be connected with the indoor experiment.It can be seen that artificial aquatic plants have a certain value in the purification of polluted rivers.