National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
Chemosphere. 2018 Oct;209:53-60. doi: 10.1016/j.chemosphere.2018.05.193. Epub 2018 May 31.
High inorganic salts inevitably impose a toxic impact on biological treatment processes. In this study, the effect of salinity on the performance and microbial community structures of partial-denitrification (PD) was firstly investigated. Results showed the denitrifying activities of non-domesticated PD sludge were completely inhibited under a temporary high salinity (≥1.5 wt%). However, after domestication, denitrifying activities maintained above 50% of the maximum with salinity build-up step-by-step from 0.0 wt% to 3.0 wt%. High nitrite production was stably achieved during 120 days with nitrate-to-nitrite transformation ratio around 90%. Further investigation showed extracellular polymeric substances content of PD sludge increased from 184.59 mg gVSS to 560.64 mg gVSS, accompanied by the elevation of average particle size. This occurred against high salinity as a protective response of PD bacteria. Moreover, Thauera, the functional bacteria of PD system, was still dominant with the relative abundance increasing to 83.36% (3.0 wt%) from 51.33% (0.0 wt%).
高浓度无机盐不可避免地会对生物处理过程造成毒害影响。本研究首先考察了盐度对部分反硝化（PD）性能和微生物群落结构的影响。结果表明，在短暂的高盐度（≥1.5wt%）条件下，非驯化 PD 污泥的反硝化活性完全受到抑制。然而，经过驯化后，反硝化活性在盐度从 0.0wt%逐步增加到 3.0wt%的过程中保持在最大活性的 50%以上。在 120 天的时间内，稳定地实现了高亚硝酸盐的生成，硝酸盐到亚硝酸盐的转化率约为 90%。进一步的研究表明，PD 污泥的胞外聚合物含量从 184.59mg gVSS 增加到 560.64mg gVSS，同时平均粒径也升高。这是 PD 细菌作为一种保护反应而对高盐度做出的反应。此外，PD 系统的功能菌 Thauera 仍然占主导地位，其相对丰度从 51.33%（0.0wt%）增加到 83.36%（3.0wt%）。
