摘要
提出在全程自养脱氮(CANON)工艺中采用长短周期交替的方式抑制亚硝酸盐氧化菌(NOB),在长周期采用原位游离氨(FA)抑制NOB,当FA浓度低于NOB抑制阈值时,在短周期采用底物抑制的方式持续抑制NOB的活性.试验设置两组序批式反应器R1、R2,分别采用不同的长短周期交替模式.结果表明:R1、R2均取得良好的脱氮效果,R2的脱氮效果稍优于R1,R1、R2的总氮去除率(NRE)分别为78.73%、85.41%,出水NO_(3)^(-)-N浓度分别为14.02mg/L和7.21mg/L. R1、R2的比硝态氮生成速率(SNPR)在64d时分别降低至2.88,1.95mgN/(gMLVSS·h),NOB活性均得到了有效抑制.胞外聚合物(EPS)结果分析表明,长短周期交替的策略有利于促进微生物分泌EPS,R1、R2的EPS含量分别从接种时的40.22mg/gVSS上升至86.41和97.79mg/gVSS.高通量测序结果表明,系统内优势菌门为变形菌门(Proteobacteria)、拟杆菌门(Bacteroidota)和浮霉菌门(Planctomycetota).R1、R2以Nitrospira和Nitrobacter为代表的NOB生长均受到抑制,Nitrospira相对丰度由接种污泥的2.05%降至0.18%(R1)和0.11%(R2),Nitrobacter的丰度由接种污泥的1.97%降低到0.06%(R1)和0.05%(R2),AnAOB(Candidatus_Brocadia)丰度分别为8.92%(R1)和9.14%(R2),AOB(Nitrosomonas)丰度分别为4.28%(R1)和6.56%(R2),形成良好的协同作用.
This study proposes a strategy to inhibit nitrite-oxidizing bacteria(NOB)in the completely autotrophic nitrogen removal over nitrite(CANON)process by alternating long and short operational cycles.During long cycles,in-situ free ammonia(FA)was used to suppress NOB,while in short cycles,substrate inhibition was employed to continuously suppress NOB activity when FA concentrations fall below the inhibitory threshold for NOB.Two sets of SBR,R1 and R2,were operated with different long-short cycle alternation patterns.The results show that both R1 and R2 achieved good nitrogen removal efficiencies(NRE),with R2 slightly outperforming R1.The NRE for R1 and R2 were 78.73%and 85.41%,respectively,while the effluent NO_(3)^(-)-N concentrations were 14.02mg/L and 7.21mg/L,respectively.At day 64,the specific nitrate production rates(SNPR)of R1 and R2 decreased to 2.88 and 1.95mgN/(gMLVSS·h),respectively,indicating effective suppression of NOB activity.Analysis of extracellular polymeric substances(EPS)revealed that the alternating long and short cycle strategy promoted microbial EPS secretion.The EPS content in R1and R2increased from 40.22mg/gVSS at inoculation to 86.41mg/gVSS and 97.79mg/gVSS,respectively.High-throughput sequencing results indicated that the dominant bacterial phyla in the system were Proteobacteria,Bacteroidota,and Planctomycetota.The growth of NOB,represented by Nitrospira and Nitrobacter,was inhibited in both R1 and R2.The relative abundance of Nitrospira decreased from 2.05%in the inoculated sludge to 0.18%in R1and 0.11%in R2,while Nitrobacter abundance dropped from 1.97%to 0.06%in R1 and 0.05%in R2.Meanwhile,the abundance of AnAOB,(Candidatus_Brocadia)reached 8.92%(R1)and 9.14%(R2),and AOB,(Nitrosomonas)achieved abundances of 4.28%(R1)and 6.56%(R2),establishing a well-coordinated synergy.
作者
李冬
付靓
赖会彬
李尧
张杰
LI Dong;FU Liang;LAI Hui-bin;LI Yao;ZHANG Jie(Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering,Beijing University of Technology,Beijing 100124,China;State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology,Harbin 150090,China)
出处
《中国环境科学》
北大核心
2025年第8期4256-4265,共10页
China Environmental Science
基金
北京高校卓越青年科学家计划项目(BJJWZYJH01201910005019)。
