Research On The Advanced Treatment Of ANAMMOX Effluent By Constructed Wetland-microbial Fuel Cell System

In view of the high concentration of total nitrogen in the effluent from ANAMMOX treatment of high-nitrogen wastewater,constructed wetland-microbial fuel cell（CW-MFC）reactor was used as the advanced treatment process.The advanced treatment effect of CW-MFC on ANAMMOX effluent under different carbon sources was detected when the water quality index of ANAMMOX effluent was at fluctuating state.The principal components analysis of the start-up process and the advanced treatment process were conducted with 3D fluorescence spectrum and parallel factor method.And the CW-MFC voltage was used as a monitoring index for COD,which could provide a basis for accurate carbon source addition in the treatment of high-nitrogen wastewater in the future.The main contents and achievements of this paper are as follows:（1）The ANAMMOX UASB reactor was constructed,and the changes of various water quality indexes of the effluent during the start-up process were explored.ANAMMOX UASB reactor was inoculated with anaerobic sludge from a sewage treatment plant in Hefei,and high nitrogen wastewater was simulated artificially.It was found that the removal of NH₄⁺-N and NO₂^--N were all above 98%,and both?NO₃^--N/?NH₄⁺-N and?NO₂^--N/?NO₃^--N were close to the theoretical value.At the 185 day,ANAMMOX becomes the dominant reaction,and after 210 days,ANAMMOX was successfully started.（2）The CW-MFC system was constructed,and the changes of electric voltage as well as other water quality indexes during the startup process were explored.Carbon felt and activated carbon were used as the cathode and anode,respectively;meanwhile,canna was chosen as wetland plant in the CW-MFC system.The anaerobic sludge was inoculated from a sewage treatment plant in Hefei,while the influent was artificial simulated sewage water.The study found that after 40 days of operation,all of the indexes of the CW-MFC system gradually reached stability,and the power generation condition was in good condition,with the output voltage about 400 m V;meanwhile,the canna grew well.（3）The advanced treatment effect of CW-MFC system on ANAMMOX UASB effluent under different carbon sources was explored,and the optimal condition parameters of the system were determined,by combining CW-MFC generation voltage and 3D fluorescence spectrum.The results showed that when the influent COD concentration ranged from 50 mg/L to 100 mg/L,the average removal rate of NH₄⁺-N was the highest,ranging from 87±1.37%to 93±1.72%.When the influent COD concentration was in the range of 125～150 mg/L,the average NO₃^--N removal rate was the highest,ranging from 83±1.63%to 86±1.37%.The correlation coefficient between influent COD concentration（50～150 mg/L）and CW-MFC system power generation voltage was about 0.898,showing a certain correlation,which provided a basis for the realization of accurate carbon source addition in the future.（4）The changes of principal components of ANAMMOX effluent during the start-up and stable process of ANAMMOX UASB and CW-MFC reactors were characterized by combining three-dimensional fluorescence spectra and parallel factor method.And the three-dimensional fluorescence spectra of ANAMMOX effluent during the advanced treatment by CW-MFC under different carbon sources were analyzed.The results showed that during the start-up and stable process of ANAMMOX UASB reactor,both the fluorescence intensity of fulvic-like substances and humic acid-like substances gradually decreased and tended to be stable.During the stable process of CW-MFC,both the fluorescence intensity of protein-like substances and riboflavin substances gradually decreased and tended to be stable.Under different carbon sources,during the advanced treatment of ANAMMOX effluent by CW-MFC,protein-like substances and fulvic-like substances finally reached similar fluorescence intensity.Since glucose did not fluoresce and the dosage was not large,the final fluorescence intensity did not differ much.Figure[25]table[10]reference[144]...