摘要
在序批式反应器(SBR)中,采用乙酸钠为碳源,通过硝酸钠和硝酸钙的交替投加、微量元素的投加以及碳氮比(COD/NO_(3)^(−)-N)的改变,探究了不同控制条件对反硝化性能及NO_(2)^(−)-N积累的影响,并分析了反应器中微生物种群演替特征。结果表明,在以乙酸钠为碳源的SBR中,Ca^(2+)浓度过高会抑制反硝化。以NaNO_(3)为NO_(3)^(−)-N来源时,硝酸盐氮还原率维持在50%左右;相同条件下,以Ca(NO_(3))_(2)为NO_(3)^(−)-N来源时,硝酸盐氮还原率仅有20%。反应器中补充适量磷元素后,硝酸盐氮还原率提高至62%,同时有少量的亚硝酸盐氮积累。当C/N比提高为4后,硝酸盐氮还原率大于98%,长期运行下亚硝酸盐氮积累率平均为83.8%。高通量测序分析结果表明,变形菌门和拟杆菌门在系统中占主导地位。NO_(2)^(−)-N积累的关键功能菌属是Thauera菌属,其最高占比为17.25%。以Ca(NO_(3))_(2)为NO_(3)^(−)-N来源时,Thauera菌属占比仅为0.14%。以上研究结果为短程反硝化的快速启动和稳定运行提供参考。
Sodium acetate was used as the carbon source in a sequencing batch reactor(SBR),and the effects of different control conditions on denitrification performance and NO_(2)^(−)-N accumulation were investigated by alternate dosing of sodium nitrate and calcium nitrate,the dosing of trace elements and the change of C/N ratio,and the characteristics of microbial population succession in SBR were also analyzed.The results showed that high Ca^(2+)concentration inhibited denitrification performance in the SBR reactor with sodium acetate as the carbon source.The nitrate nitrogen reduction rate was maintained at about 50%when NaNO_(3) was used as the NO_(3)^(−)-N source;under the same conditions,the nitrate nitrogen reduction rate was only 20%when Ca(NO_(3))_(2) was used as the NO_(3)^(−)-N source.When SBR was supplemented with appropriate amount of phosphorus,the nitrate reduction rate could increase to 62%,while the accumulation of a small amount of nitrite occurred.When the carbon to nitrate ratio(COD/NO_(3)^(−)-N)increased to 4,the nitrate reduction rate was greater than 98%,and the nitrite accumulation rate was 83.8%on average under long-term operation.High-throughput sequencing analysis showed that Proteobacteria and Bacteroidetes dominated the system,the key functional genus for NO_(3)^(−)-N accumulation was Thauera,which had the highest percentage of 17.25%.The percentage of Thauera was only 0.14%when Ca(NO_(3))_(2) was used as the source of NO_(3)^(−)-N.These results provide a theoretical support for the rapid start-up and stable operation of partial denitrification.
作者
康沛伦
李俊达
叶晟祺
陈泽彬
黄博创
崔理华
余光伟
梁瑜海
KANG Peilun;LI Junda;YE Shengqi;CHEN Zebin;HUANG Bochuang;CUI Lihua;YU Guangwei;LIANG Yuhai(College of Natural Resources and Environment,South China Agricultural University,Guangdong Provincial Key Laboratory of Agricultural&Rural Pollution Abatement and Environmental Safety,Guangzhou 510642,China;Guangdong Laboratory for Lingnan Modern Agriculture,Guangzhou 510642,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2022年第8期2540-2548,共9页
Chinese Journal of Environmental Engineering
基金
广东省自然科学基金-面上项目(2021A1515010904)
国家自然科学基金资助项目(51708229)
广东省科技计划项目(2021B1212040008)。
关键词
短程反硝化
阳离子
碳氮比
微生物种群
partial denitrification
cation
COD/NO_(3)^(−)-N
microbial community
