National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, 100 Ping Le Yuan, Chaoyang District, Beijing, 100124, People's Republic of China.
Bioprocess Biosyst Eng. 2020 Dec;43(12):2143-2152. doi: 10.1007/s00449-020-02400-x. Epub 2020 Jul 4.
The effects of different carbon sources on the enrichment of 2,4,6TCP-degrading microbes and on reactor stability were was investigated using a lab-scale sequencing batch reactor (SBR). Glucose, sucrose, and starch were selected as different carbon sources because of the different molecular weights. The sucrose-fed activated sludge (AS) exhibited faster adaption and higher degradation rates for 2,4,6-TCP in long-term operation and typical cycles compared to that fed with glucose and starch. Large amounts of extracellular polymeric substance (EPS; 117.54 mg/gVSS) were induced from AS after adding starch, leading to a high SVI (191 mL/g) and poor sludge settling. This suggests that macromolecular carbon sources might have a detrimental effect on the reactor operation. Moreover, the high removal efficiency for TOC and chloride ions was achieved in a typical cycle of all SBRs, indicating that AS could completely mineralize 2,4,6-TCP. On average, more than 90% of the COD could be removed in all SBRs during long-term operation. Glucose, sucrose, and starch facilitated the development of a different microbial community compared to the seeding sludge, making Chloroflexi, Actinobacteria, and Proteobacteria the dominant phylum in the corresponding SBR. The microbial abundance associated with the metabolism of 2,4,6-TCP reached 81.02% due to the addition of sucrose. The results of this study could provide a potential guide for the effective selection of carbon sources in the treatment of chlorophenol wastewater.
采用实验室规模的序批式反应器（SBR）研究了不同碳源对 2,4,6-TCP 降解微生物富集和反应器稳定性的影响。选择葡萄糖、蔗糖和淀粉作为不同的碳源，是因为它们具有不同的分子量。与葡萄糖和淀粉相比，在长期运行和典型周期中，以蔗糖为食的活性污泥（AS）对 2,4,6-TCP 的适应速度更快，降解速度更高。在添加淀粉后，AS 中诱导产生了大量的胞外聚合物（EPS；117.54 mg/gVSS），导致 SVI（191 mL/g）较高且污泥沉降性能较差。这表明，大分子碳源可能对反应器运行有不利影响。此外，所有 SBR 中的典型周期都实现了 TOC 和氯离子的高去除效率，表明 AS 可以完全矿化 2,4,6-TCP。在长期运行期间，平均而言，所有 SBR 中都可以去除超过 90%的 COD。与接种污泥相比，葡萄糖、蔗糖和淀粉促进了不同微生物群落的发展，使绿弯菌门、放线菌门和变形菌门成为相应 SBR 中的优势门。由于添加了蔗糖，与 2,4,6-TCP 代谢相关的微生物丰度达到了 81.02%。本研究的结果可为处理氯酚废水时有效选择碳源提供潜在指导。
