硫自养反硝化耦合厌氧氨氧化脱氮系统快速启动及微生物群落分析

RAPID START-UP AND MICROBIAL COMMUNITY ANALYSIS OF A SULFUR AUTOTROPHIC DENITRIFICATION COUPLED ANAEROBIC AMMONIA OXIDATION DENITRIFICATION SYSTEM

以硫代硫酸钠为电子供体,采用梯度增加基质负荷的方式,在SBR反应器中完成硫自养反硝化(SAD)工艺启动。通过接种厌氧氨氧化(Anammox)污泥,采用pH和NO_(3)^(-)-N/NH_(4)^(+)-N联合调控策略进行研究,实现硫自养反硝化耦合厌氧氨氧化(SAD/A)自养脱氮系统快速启动及稳定运行。结果表明:30 d成功将反硝化污泥驯化为SAD污泥,90 d后,SBR反应器成功富集SAD污泥,系统NO_(3)^(-)-N去除率可达到85%以上。SAD/A系统2种种泥最佳接种比为3∶1,运行14 d后SAD/A系统成功启动。30 d后,系统NO_(3)^(-)-N去除率可达到85%,NH_(4)^(+)-N去除率达到80%。pH值为8,且ρ(NO_(3)^(-)-N)/ρ(NH_(4)^(+)-N)为1.8时,耦合系统脱氮效率最佳,实现稳定运行。高通量测序结果表明:SAD/A系统整体的物种多样性和丰富度增加,优势微生物菌属为厌氧氨氧化菌属(Candidatus Brocadia)和硫杆菌属(Thiobacillus),二者相对丰度相近,系统耦合度较好。

In this paper,the sulfur autotrophic denitrification(SAD)process start-up was accomplished in an SBR reactor using sodium thiosulfate as an electron donor,and a gradual increase in substrate loading.The rapid start-up and stable operation of the sulfur autotrophic denitrification coupled with anaerobic ammonia oxidation(SAD/A)autotrophic denitrification system was developed by inoculating Anammox sludge with a combined pH and NO_(3)^(-)-N/NH_(4)^(+)-N regulation strategy.The results showed that in 30 days,the denitrification sludge had been domesticated into SAD sludge.After 90 days,the SBR reactor had been successfully enriched with SAD sludge,and more than 85%of NO_(3)^(-)-N had been removed from the system.The SAD/A system was successfully started after 14 days of operation with an optimal inoculation ratio of 3∶1 for both two species of sludge.After 30 days,the NO_(3)^(-)-N removal rate of the system could reach 85%and the NH_(4)^(+)-N removal rate could reach 80%.The coupled system’s best denitrification efficiency was achieved at a pH of 8 and a NO_(3)^(-)-N/NH_(4)^(+)-N ratio of 1.8,and it operated steadily.High-throughput sequencing results showed that the overall species diversity and richness in the SAD/A system was increased after coupling,and the dominant microbial genera were Candidatus Brocadia and Thiobacillus,with similar relative abundances,indicating a good coupling effect of SAD/A.