Department of Process and Life Science Engineering, Division of Chemical Engineering, Lund University, PO Box 124, SE-221 00 Lund, Sweden.
Department of Process and Life Science Engineering, Division of Chemical Engineering, Lund University, PO Box 124, SE-221 00 Lund, Sweden.
J Hazard Mater. 2024 Jul 5;472:134449. doi: 10.1016/j.jhazmat.2024.134449. Epub 2024 Apr 26.
The capacity for organic micropollutant removal in granular activated carbon (GAC) filters for wastewater treatment changes over time. These changes are in general attributed to changes in adsorption, but may in some cases also be affected by biological degradation. Knowledge on the degradation of organic micropollutants, however, is scarce. In this work, the degradation of micropollutants in several full-scale GAC and sand filters was investigated through incubation experiments over a period of three years, using C-labeled organic micropollutants with different susceptibilities to biological degradation (ibuprofen, diclofenac, and carbamazepine), with parallel 16S rRNA gene sequencing. The results showed that the degradation of diclofenac and ibuprofen in GAC filters increased with increasing numbers of bed volumes when free oxygen was available in the filter, while variations over filter depth were limited. Despite relatively large differences in bacterial composition between filters, a degradation of diclofenac was consistently observed for the GAC filters that had been operated with high influent oxygen concentration (DO >8 mg/L). The results of this comprehensive experimental work provide an increased understanding of the interactions between microbial composition, filter material, and oxygen availability in the biological degradation of organic micropollutants in GAC filters.
在废水处理中，颗粒活性炭（GAC）过滤器对有机微量污染物的去除能力会随时间而变化。这些变化通常归因于吸附的变化，但在某些情况下也可能受到生物降解的影响。然而，有关有机微量污染物降解的知识却很匮乏。在这项工作中，通过为期三年的培养实验，使用对生物降解具有不同敏感性的 C 标记有机微量污染物（布洛芬、双氯芬酸和卡马西平）以及平行的 16S rRNA 基因测序，研究了几种全规模 GAC 和砂滤器中微量污染物的降解情况。结果表明，当过滤器中存在游离氧时，GAC 过滤器中双氯芬酸和布洛芬的降解随床体积的增加而增加，而过滤器深度的变化则受到限制。尽管过滤器之间的细菌组成存在较大差异，但对于以高进水氧浓度（DO>8mg/L）运行的 GAC 过滤器，始终观察到双氯芬酸的降解。这项全面的实验工作的结果提供了对有机微量污染物在 GAC 过滤器中生物降解过程中微生物组成、过滤材料和氧气供应之间相互作用的深入了解。
