ABSTRACT

Nickel (ii) (Ni²⁺) is considered as one of the necessary trace elements in the process of Anammox culture, but it may have toxic effects at high concentration. This study explored the long-term influence of Ni²⁺ on the denitrification efficiency of Anammox bioreactors. The results showed that when the concentration of Ni²⁺ was 0.5 mg/L, the bioreactor had the highest denitrification efficiency, while the removal efficiency of ammonia nitrogen and nitrite nitrogen gradually decreased at concentrations higher than 2 mg/L, and the removal rates of ammonia nitrogen and nitrite nitrogen were 26% and 39.81% at the end of the experiment, respectively. The NRR was decreased from 7.47 kg N/m³ d to 3.28 kg N/m³ d during the whole process. The highest concentration of microbial dehydrogenase was attained in about 40 days; in the meantime, its ability to consume organic matter was also maximized. The sludge morphology was changed from granular cluster to loose flocculant with a small number of spherical and filamentous bacteria and bacilli distributed on the surface. At the end of the experiment, both species richness and community diversity were reduced, and the proportion of the dominant bacteria Candidatus Kuenenia was also decreased from 59.89% to 36.72%.

摘要

镍（ii）（Ni ²⁺）被认为是厌氧氨氧化培养过程中必需的微量元素之一，但在高浓度下可能会产生毒性作用。^{本研究探讨了 Ni 2+}对厌氧氨氧化生物反应器反硝化效率的长期影响。结果表明，当Ni ²⁺浓度为0.5 mg/L时，生物反应器的反硝化效率最高，而氨氮和亚硝酸盐氮的去除效率在浓度高于2 mg/L时逐渐降低，去除率实验结束时氨氮和亚硝酸盐氮的含量分别为26%和39.81%。NRR 从 7.47 kg N/m ³  d 降至 3.28 kg N/m ³ d 在整个过程中。在大约 40 天内达到最高浓度的微生物脱氢酶；与此同时，它消耗有机物的能力也得到了最大化。污泥形态由粒状簇状变为疏松絮状，表面分布有少量球形和丝状细菌和杆菌。实验结束时，物种丰富度和群落多样性均有所降低，优势菌Candidatus Kuenenia的比例也从59.89%降至36.72%。