Distribution variation of a metabolic uncoupler, 2,6-dichlorophenol (2,6-DCP), in long-term sludge culture was studied, and the effects on sludge reduction and biological inhibition of this chemical during the 90-day operation were established. The extracellular polymeric substance (EPS) matrix functioned as a protective barrier for the bacteria inside sludge flocs to 2,6-DCP, resulting in the transfer of 2,6-DCP from the liquid phase to the activated sludge fraction. Significant sludge reduction (about 40%) was observed after the addition of 2,6-DCP in the first 40 days, while the ineffective function of 2,6-DCP in sludge reduction (days 70-90) might be correlated to the EPS protection mechanism. The inhibitory effect of 2,6-DCP on the COD removal was extremely lower than on the nitrification performance due to the fact that 2,6-DCP was much more toxic to autotrophic microorganisms than heterotrophic microorganisms. Moreover, both of them recovered to a higher level again with the transfer potential of 2,6-DCP to sludge. Thus, the application of metabolic uncoupler for excess sludge reduction should be cautious.

中文翻译：

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代谢解偶联剂2,6-二氯苯酚（2,6-DCP）在长期污泥培养中的分布变化及其对污泥减少和生物抑制的影响。

研究了在长期污泥培养中代谢解偶联剂2,6-二氯苯酚（2,6-DCP）的分布变化，并确定了90天操作期间该化学品对污泥减少和生物抑制的影响。细胞外聚合物质（EPS）基质对污泥絮凝物中的细菌转化为2,6-DCP起到保护性屏障的作用，从而导致2,6-DCP从液相转移到活化的污泥馏分中。在开始的40天中，添加2,6-DCP后观察到显着的污泥减少（约40％），而2,6-DCP在减少污泥（第70-90天）中无效的作用可能与EPS相关。保护机制。2，6-DCP对COD去除的抑制作用远低于对硝化性能的抑制作用，这是因为，6-DCP对自养微生物的毒性比异养微生物大得多。此外，它们都以2,6-DCP转移至污泥的潜力再次恢复到较高水平。因此，应谨慎使用代谢解偶联剂减少过多的污泥。