Optimization Of The Treatment Of Aquaculture Wastewater By Myriophyllum Aquaticum-biofilm Membrane

The stabilization pond,as a process with good treatment effect on aquaculture wastewater and low investment and construction cost,was easily affected by seasonal temperature.Based on this,this project used the combined action of Myriophyllum aquaticum and biofilm to strengthen the stabilization pond to remove target pollutants in aquaculture wastewater at different temperatures and different concentrations.The effect on the removal of pollutants in different environments was intended to provide a reference for the advanced treatment of aquaculture wastewater by Myriophyllum aquaticum-biofilm enhanced stabilization ponds.The results were summarized as following:1)At low temperature,the aeration group had a removal rate of 68.5% in 20 days at low concentration and 68.3% in 40 days at high concentration,indicating that increasing the aeration can quickly improve the removal efficiency of ammonia nitrogen at low temperature.Under aeration,the higher the concentration,the longer it took to reach the same efficiency.2)At low concentrations,the removal effect of biofilm on total nitrogen was 70.4% better than that of Myriophyllu aquaticum-biofilm 65.2% and better than that of Myriophyllum aquaticum 51.6%,and the removal effect of total phosphorus by 65.8% was lower than that of Myriophyllum aquaticum-biofilm 92.8% and Myriophyllum aquaticum 95.3%.At high concentration,the removal effect of total nitrogen by biofilm was 76.9% better than that of Myriophyllum aquaticum-biofilm 65.5% and better than that of Myriophyllum aquaticum 50.7%,and the removal effect of total phosphorus by Myriophyllum aquaticum-biofilm was 79.1% better than biofilm 57.3% better than Myriophyllum aquaticum 39.3%.It shows that the pure Myriophyllum aquaticum had a poor removal effect of nitrogen and phosphorus in sewage.In actual application,a biofilm should be added to strengthen the removal effect of nitrogen and phosphorus by a stable pond system.3)At high temperature,the mass of Myriophyllum aquaticum died and the biomass decreased,so that the total phosphorus concentration in the sewage increased without decreased.However,Myriophyllum aquaticum had better nitrogen removal effect than that of Myriophyllum aquaticum-biofilm was better than biofilm.The rusults showed the death of Myriophyllum aquaticum provided a carbon source for sewage and promotes the removal of ammonia nitrogen.4)At high temperature,the removal rate of ammonia nitrogen was about 70% and the total nitrogen removal rate was about 60%.At low temperature,the removal rate of ammonia nitrogen and total nitrogen was about 20%.It showed that in the stable pond system,high temperature was more favorable for nitrogen removal than low temperature.Among them,the removal rate of ammonia nitrogen was about 60% high temperature than that of low temperature,and the removal rate of total nitrogen was about 40% high temperature than that of low temperature.