Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China.
School of Civil & Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, PR China.
Environ Res. 2021 Jun;197:111029. doi: 10.1016/j.envres.2021.111029. Epub 2021 Mar 17.
Sulfur autotrophic denitrification (SAD) process, as an alternative to heterotrophic denitrification (HD) filter, receives growing interest in polishing the effluent from secondary sewage treatment. Although individual studies have indicated several advantages of SAD over HD, rare study has compared these two systems under identical condition and by using real secondary effluent. In this study, two small pilot scale filters (SAD and HD) were designed with identical configuration and operated parallelly by feeding the real secondary effluent from a WWTP. The results showed SAD filter can be started up without the addition of soluble electron donor, although the time (14 days) was about 3 times longer than that of HD filter. The nitrate removal rate of SAD filter at HRT of 1.4 h was measured as 0.268 ± 0.047 kg N/(m∙d). Similar value was observed in HD filter with supplementing 90 mg/L COD. The COD concentration of effluent always kept lower than that of influent in SAD filter but not in HD filter. In addition, SAD filter could maintain a stable denitrification performance without backwash for 15 days, while decline of nitrate removal rate was observed in HD filter just 2 days after stopping the backwash. This different behavior was further confirmed as the SAD filter had a better hydraulic flow pattern. Analysis according to high-throughput 16S rRNA gene-based Illumina MiSeq sequencing clearly showed the microbial community evolution and differentiation among the samples of seed sludge, SAD and HD filters. Finally, the economic assessment was carried out, showing the operation cost of SAD filter was over 50% lower than that of HD filter.
硫自养反硝化（SAD）工艺作为异养反硝化（HD）滤池的替代方法，在二级污水处理的出水深度处理中受到越来越多的关注。尽管个别研究表明 SAD 比 HD 具有多项优势，但很少有研究在相同条件下并使用实际二级出水来比较这两种系统。在这项研究中，设计了两个小型中试规模的过滤器（SAD 和 HD），它们具有相同的配置，并通过使用来自 WWTP 的实际二级出水进行平行运行。结果表明，SAD 过滤器可以在不添加可溶电子供体的情况下启动，尽管时间（14 天）比 HD 过滤器长约 3 倍。在 HRT 为 1.4 h 的情况下，SAD 过滤器的硝酸盐去除率为 0.268±0.047 kg N/(m·d)。在补充 90 mg/L COD 的 HD 过滤器中观察到类似的值。SAD 过滤器的出水 COD 浓度始终低于进水，而 HD 过滤器则不然。此外，SAD 过滤器在不进行反冲洗的情况下可以稳定地保持 15 天的反硝化性能，而在停止反冲洗两天后，HD 过滤器的硝酸盐去除率则下降。这种不同的行为进一步证实了 SAD 过滤器具有更好的水力流动模式。根据高通量 16S rRNA 基因基于 Illumina MiSeq 测序的分析清楚地表明了样品中微生物群落的进化和分化，包括种子污泥、SAD 和 HD 过滤器。最后，进行了经济评估，结果表明 SAD 过滤器的运行成本比 HD 过滤器低 50%以上。
