Analysis on performance of denitrification artificial wetland in advanced treating dispersed swine wastewater
To adapt to the increasingly stringent requirements for surface water environment,it is necessary to construct the artificial wetland of strengthened nitrification area for treating the dispersed swine wastewater for strengthened denitrification.The constructed wetland reactor(2 m×1 m×0.75 m)was prepared with gravel,brick debris,mixture of zeolite and limestone and fine sand as the substrate.The start-up phase performance of the reactor was evaluated under the conditions of COD,ammonia nitrogen,and total phosphorus concentration in influent of 150,110 and 25 mg/L,respectively.After completion of start-up,COD concentration in influent was increased to 200 mg/L to examine the effect of COD load.In comparison,ammonia nitrogen concentration in influent was increased to 200 mg/L to evaluate the effect of ammonia nitrogen load.The nitrogen removal pathways in the reactor were analyzed.The results showed that during the inoculation stage,zeolite achieved adsorption-regeneration equilibrium,and the operational performance of the reactor was stable.At the end of the reactor,the adsorption concentration of ammonia nitrogen was approximately 45 mg/L,and the concentration of nitrate nitrogen produced was approximately 60 mg/L.When COD concentration in influent was increased,the removal rate of COD was kept at about 77.50%,and ammonia nitrogen concentration in influent was increased,but ammonia nitrogen concentration did not increase obviously,it was stable at about 30mg/L.The results showed that the constructed wetland had stable operation and good effect of deep nitrogen removal,which could be used for practical application.
万方数据
维普
