IFFAS工艺中厌氧氨氧化与反硝化协同脱氮研究OA

Under low carbon-to-nitrogen(C/N)ratio conditions,anaerobic ammonium-oxidizing bacteria can synergize with heterotrophic denitrifying bacteria for nitrogen removal.However,the interaction between these two microbial groups under varying carbon-to-nitrogen ratios remains unclear.To enhance their synergistic denitrification effect,an integrated floating-film activated sludge(IFFAS)process reactor based on zero-valent iron(ZVI)modified carriers is constructed,and the effect of different influent carbon-to-nitrogen ratios(C/N=0.3-0.8)on the system is investigated.Experimental results show that low carbon-to-nitrogen ratio(C/N=0.3)conditions favor maintaining higher extracellular polymeric substances(EPS)concentration,heme C content,key enzyme activity and overall nitrogen removal efficiency in the system.At C/N of 0.3 and 0.5,the total nitrogen removal rates in the modified carrier reactor are 82％and 72％,respectively,both exceeding those of the conventional carrier reactor by over 10％.At C/N=0.3,the relative abundances of typical anaerobic ammonium-oxidizing bacteria genera Candidatus_Jettenia and Candidatus_Kuenenia in the modified carrier biofilm reach 30.60％,which is 5.67％higher than the control group.The findings confirm that modified carrier biofilms have an advantage in promoting the synergistic denitrification of anaerobic ammonium oxidation and denitrification in low carbon-to-nitrogen ratio wastewater.