The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China.
Environmental Engineering Research Centre, Department of Civil Engineering, The University of Hong Kong, Pokfulam, Hong Kong, China; Tsinghua-Berkeley Shenzhen Institute, Tsinghua University, Shenzhen, China.
Water Res. 2020 May 15;175:115646. doi: 10.1016/j.watres.2020.115646. Epub 2020 Feb 26.
A novel wastewater treatment process, which couples chemically enhanced primary sedimentation (CEPS) of sewage with acidogenic fermentation of sludge in tandem, has recently been developed to improve the removal of pollutants and nutrients, and recover valuable resources such as phosphorus and organics. This study represented the first laboratory-based examination on the level and removal of the emerging contaminants, including retinoids (i.e., retinoic acids (RAs) and their metabolites) and oestrogenic endocrine disrupting chemicals (EDCs; e.g., 4-nonylphenol, bisphenol A, etc.), in sewage, sludge and its supernatant during this novel wastewater treatment process. The results showed that 65% of retinoids and 73% of EDCs were removed from sewage after aluminum (Al) based CEPS, while 80% of retinoids and 72% of EDCs were removed after iron (Fe) based CEPS. After acidogenic fermentation of the CEPS sludge, 50% and 58% of retinoids, and 50% and 47% of EDCs were further removed in the supernatants of Al-sludge and Fe-sludge, respectively. While there were comparable removals for these two classes of emerging contaminants during Al- and Fe-based CEPS and sludge fermentation, Fe-based CEPS of sewage and sludge fermentation should be preferentially considered, given the relatively lower production of Fe-sludge and lower accumulation of retinoids in Fe-sludge. The levels of retinoids and EDCs in the supernatant and sludge changed during acidogenic fermentation of Fe-sludge. The removals of at-4-oxo-RA (i.e., the dominant retinoid) and bisphenol A (i.e., the dominant EDC) in the supernatant followed the pseudo first-order reaction model, with a half-life of 1.62 days (in the first two days) and 1.55 days (in the whole experiment of seven days), respectively. The results demonstrated the effective removal of emerging contaminants from the sewage and the supernatant during the CEPS and acidogenic sludge fermentation.
一种新型的废水处理工艺，将污水的化学强化一级沉淀（CEPS）与污泥的产酸发酵串联起来，最近被开发出来，以提高污染物和营养物质的去除率，并回收磷和有机物等有价值的资源。本研究首次在实验室水平上研究了包括类视黄醇（即视黄酸（RA）及其代谢物）和雌激素类内分泌干扰物（EDC；如壬基酚、双酚 A 等）在内的新兴污染物在污水、污泥及其上清液中的水平和去除情况。结果表明，经过铝（Al）基 CEPS 处理后，污水中有 65%的类视黄醇和 73%的 EDC 被去除，而经过铁（Fe）基 CEPS 处理后，污水中有 80%的类视黄醇和 72%的 EDC 被去除。经过 CEPS 污泥的产酸发酵后，在 Al 污泥和 Fe 污泥的上清液中，分别有 50%和 58%的类视黄醇和 50%和 47%的 EDC 进一步被去除。虽然 Al 和 Fe 基 CEPS 及污泥发酵对这两类新兴污染物的去除效果相当，但鉴于 Fe 污泥的产量较低，且 Fe 污泥中类视黄醇的积累较少，因此应优先考虑采用 Fe 基 CEPS 处理污水和污泥发酵。在 Fe 污泥的产酸发酵过程中，上清液和污泥中的类视黄醇和 EDC 水平发生了变化。上清液中 at-4-氧-RA（即主要的类视黄醇）和双酚 A（即主要的 EDC）的去除遵循假一级反应模型，半衰期分别为 1.62 天（前两天）和 1.55 天（整个 7 天实验）。结果表明，在 CEPS 和产酸污泥发酵过程中，可有效去除污水和上清液中的新兴污染物。
