生活垃圾焚烧厂渗沥液厌氧氨氧化脱氮效能及微生物机理分析

生活垃圾焚烧厂渗沥液是一种含高氨氮高有机物浓度的难处理废水，目前渗沥液生物脱氮多采用多级硝化反硝化处理工艺，存在能耗大、效率低等不足。以厌氧氨氧化技术为核心，构建连续流厌氧消化-短程硝化-厌氧氨氧化三段式工艺，分析垃圾焚烧厂渗沥液的生物脱氮效果、有机物迁移转化规律、功能微生物活性及组成变化。结果表明:在进水ρ（NH₄+-N）为900~1800 mg/L，ρ（COD）为3000~20000 mg/L时，系统处理效果良好，稳定运行期间总无机氮和COD去除率分别为85%和77%。其中厌氧消化段可去除约45%的COD，短程硝化段NO₂--N积累率保持在97%以上，厌氧氨氧化段稳定运行期间总无机氮去除率约为85%，系统内也存在一定程度反硝化反应。接入渗沥液后，自养脱氮体系中功能微生物氨氧化菌（AOB）和厌氧氨氧化菌（Anammox）的活性均有不同程度的下降，采用宏基因组学结合16S rDNA高通量测序技术对比分析微生物的群落和功能组成变化，发现渗沥液中高浓度的有机物使短程硝化段和厌氧氨氧化段内异养反硝化菌相对丰度上升，Anammox受到难降解有机物抑制，其中Candidatus_Kuenenia菌属适应性较强，在驯化后仍然可以维持厌氧氨氧化系统较高的脱氮效果。

TREATMENT OF LEACHATE FROM MUNICIPAL SOLID WASTE INCINERATION PLANT BY COMBINED ANAMMOX PROCESS: NITROGEN REMOVAL AND MICROBIAL MECHANISM

Leachate from municipal solid waste incineration plants is a kind of refractory wastewater with a high concentration of ammonia nitrogen and organic matter. Multi-stage nitrification and denitrification process is often used for biological denitrification of leachate, which has the disadvantages of high energy consumption and low efficiency. In this study, a continuous flow three-stage process of anaerobic digestion-partial nitrification-anammox was establish to treat the leachate with the anammox process as the key technology, and its biological denitrification effect, changes of organic matters, functional microbial activity and composition analysis of leachate from waste incineration plant were investigated. The results showed that when the influent NH₄+-N and COD concentrations were 900~1800 mg/L and 3000~20000 mg/L, respectively, and the total inorganic nitrogen (TIN) and COD removal efficiency reached 85% and 77%, respectively. Specifically, the COD removal efficiency was about 45% in the anaerobic digestion reactor. The accumulation rate of NO₂--N in the partial nitrification reactor remained 97% above, and the removal efficiency of total inorganic nitrogen was about 85% in the Anammox reactor; heterotrophic denitrification also had occurred in the system. The activity of ammonia oxidizing bacteria and anammox bacteria in the autotrophic nitrogen removal system decreased in varying degrees after the leachate added. The results of metagenomics combined with 16S rDNA high-throughput sequencing analysis showed that the relative abundance of heterotrophic denitrifiers in the partial nitrification and Anammox reactors increased, due to the high concentration of organic matters in the leachate. Specially, Anammox was inhibited by refractory organics, among which Candidatus_Kuenenia was adaptable. Nevertheless, after a long-term acclimation, the anammox bacteria could still maintain a high nitrogen removal efficiency.