Treatment Of Aquaculture Wastewater By Compound Media Bio-filter System And Integrated Constracted Wetland Reacter

Aquaculture is developing rapidly in our country,with expanding scale and increasing intensive.However,a lot of pollutants produced by excessive aquaculture and feed,such as nitrogen and phosphorus,are discharged into surroundings follow with aquaculture wastewater,destroy the ecological environment.Therefore,the treatment of aquaculture wastewater is an urgent problem.In simulation experiment,"Bio-filter?S1?+ Compound Media Bio-filter System?CMB?" and"Bio-filter?S2?+ Integrated Constracted Wetland Reacter?ICW?" were constructed,to explore the removal efficiency about the treatment of freshwater fish wastewater.The results showed that,both"S1+CMB" and "S2+ICW" have good effects on the removal of COD_Mn,NH₃-N,TN,TP in freshwater fish wastewater.The bio-filter could remove the COD_Mn,NH₃-N,TN,TP in freshwater fish wastewater obviously,it has both functions of physical filtration and microbiological degradation.Compared with the ICW,CMB has the advantages of high load and easy management,so combination of "S1+CMB"is more suitable for practical application.In consideration of simulation experiment results and actual water quality,properly adjusted the types and laying method of fillers.Then designed another experiment on the treatment of freshwater fish wastewater in the wild,which formed a water-cycle model by recycling the treated water.The operation of four months showed that,the treatment of freshwater fish wastewater by "S+CMB" was effective,the average removal rates of SS,COD_Mn,TN,TP were 70.1%,43.8%,59.9%and 48.4%respectively,the highest removal rates were 94.6%,70.5%,86.4%and 74.8%respectively.The results demonstrated that fiber-bundle material in Bio-filter could obviously filter suspended particulate matter,it meaned that filter is essential in the practical application.The filtration of aquaculture wastewater can not only prevent fillers plugging,but also remove a partial of nitrogen,phosphorus and organic matter.The combination of "S+CMB" meet the requirements of aquaculture wastewater treatment and water recycling,it is worthy of application and promotion.