Aarhus University, Department of Environmental Science, Frederiksborgvej 399, 4000 Roskilde, Denmark.
Berlin Centre of Competence for Water (KWB), Cicerostr. 24, 10709 Berlin, Germany.
Sci Total Environ. 2020 Aug 20;731:139064. doi: 10.1016/j.scitotenv.2020.139064. Epub 2020 Apr 28.
The removal of micropollutants from municipal wastewater is challenged by the number of compounds with diverse physico-chemical properties. Ozonation is increasingly used to remove micropollutants from wastewater. However, ozonation does not necessarily result in complete mineralization of the organic micropollutants but rather transforms them into new compounds which could be persistent or have adverse environmental effects. To explore ozone dose dependency of the formation and successive removal of ozonation products, two pilot-scale and one full-scale ozonation plants were operated subsequent to a conventional activated sludge treatment. The results from these trials indicated that the concentrations of several N-oxides, such as Erythromycin N-oxide, Venlafaxine N-oxide and Tramadol N-oxide, increased up to an ozone dose of 0.56-0.61 mg O/mg DOC while they decreased at elevated doses of 0.7-1.0 mg O/mg DOC. Similar results were also obtained for two transformation products of Diclofenac (Diclofenac 2,5-quinone imine and 1-(2,6-dichlorophenyl)indolin-2,3-dione) and one transformation product of Carbamazepine (1-(2-benzoic acid)-(1H,3H)-quinazoline-2,4-dione), where the highest concentrations appeared around 0.27-0.31 mg O/mg DOC. The formation maximum of a given compound occurred at a specific ozone dose that is characteristic for each compound, but seemed to be independent of the wastewater used for the experiments at the two pilots and the full-scale plant.
从市政废水中去除微量污染物受到具有不同物理化学性质的化合物数量的挑战。臭氧氧化越来越多地用于从废水中去除微量污染物。然而，臭氧氧化不一定导致有机微量污染物的完全矿化，而是将其转化为可能具有持久性或对环境有不利影响的新化合物。为了探索形成和随后去除臭氧氧化产物的臭氧剂量依赖性，在常规活性污泥处理之后，运行了两个中试规模和一个全规模的臭氧氧化装置。这些试验的结果表明，几种 N-氧化物（如红霉素 N-氧化物、文拉法辛 N-氧化物和曲马多 N-氧化物）的浓度在臭氧剂量为 0.56-0.61 mg O/mg DOC 时增加，而在 0.7-1.0 mg O/mg DOC 时降低DOC。二氯芬酸（二氯芬酸 2,5-醌亚胺和 1-(2,6-二氯苯基)吲哚啉-2,3-二酮）的两个转化产物和卡马西平的一个转化产物（1-(2-苯甲酸)-(1H,3H)-喹唑啉-2,4-二酮）也得到了类似的结果，其中在 0.27-0.31 mg O/mg DOC 左右出现了最高浓度。给定化合物的形成最大值出现在每个化合物特有的特定臭氧剂量下，但似乎与两个中试和全规模工厂使用的废水无关。
