The discovery of anaerobic ammonium oxidation processes led to the development of innovative nitrogen removal technologies, which are more cost-effective and environmentally friendly than conventional activated sludge systems. In this study, the bacterial community structure was determined as well as the nitrogen removal efficiencies in four fixed-bed biofilm bioreactors, working under different salt concentrations (0, 3, 25, and 45 g L⁻¹ of sodium chloride (NaCl)) and at hydraulic retention times (HRT) of 6 and 12 h. The influent total nitrogen concentration was 250 mg L⁻¹. The results showed a clear inhibition in the nitrogen removal capacity of the process that was directly related to the salt concentration in the influent, most likely due to changes in the bacterial community structure; increases in the NaCl concentration provoked the inhibition of Candidatus Brocardia and Nitrosomonas, whereas heterotrophic phylotypes such as Marinobacter proliferated. An evident adaptation of the anammox microorganisms at 3 g NaCl L⁻¹ was observed, whereas ammonia and nitrite oxidizing bacteria drastically decreased at 25 and 45 g NaCl L⁻¹. Total nitrogen efficiencies for 6h of HRT were 87.68, 64.25, 38.79, and 19.74%, for 0, 3, 25, and 45 g NaCl L⁻¹, respectively. No significant effects were detected on the performance of the bioreactors and bacterial diversity under different HRT. Our study may be useful for the implementation of CANON systems at real-scale, by increasing the knowledge on the bacterial community at different NaCl concentrations and the performance of this novel technology for saline wastewater treatment.

厌氧铵氧化工艺的发现导致了创新型脱氮技术的发展，该技术比传统的活性污泥系统更具成本效益和环境友好性。在这项研究中，确定了四个固定床生物膜生物反应器的细菌群落结构以及除氮效率，这些反应器在不同的盐浓度（0、3、25和45 g L ^-1的氯化钠（NaCl））下工作水力停留时间（HRT）为6和12小时。进水总氮浓度为250 mg L ^-1。结果表明，该工艺的脱氮能力受到明显的抑制，这与进水中的盐浓度直接相关，这很可能是由于细菌群落结构的改变所致。在NaCl浓度的增加引起的抑制暂定Brocardia和亚硝化单胞，而异种系型如Marinobacter增殖。在3 g NaCl L ^-1下观察到了厌氧微生物的明显适应性，而在25 g NaCl L ^-1和45 g NaCl L ^-1下，氨和亚硝酸盐氧化细菌急剧减少。对于0g，3g，25g和45g NaCl L ^-1，HRT 6h的总氮效率分别为87.68％，64.25％，38.79％和19.74％， 分别。在不同的HRT条件下，未检测到对生物反应器性能和细菌多样性的显着影响。我们的研究可能通过增加不同NaCl浓度下细菌群落的知识以及这种用于盐水处理的新技术的性能，对于大规模实施CANON系统可能有用。