废水回收和再利用是重要的方法,有助于实现需求和提供的平衡,也是减少碳排放的重要途径之一。二次出水有机物(EfOM)的存在会对再利用过程中的环境带来潜在威胁。因此,开发有效去除EfOM的中水回用技术非常重要。在这项研究中,通过使用连续流工艺(FeSDF)评估了FeCl2(Fe(VI)/Fe(II))与污泥吸附剂(SAs)结合增强的高铁酸盐的EfOM去除性能,由Fe(VI)/Fe(II)组成,SAs,densadeg和过滤。结果表明,当流入流量为1L/h时,FeSDF的最佳操作条件包括5mg/L的Fe(VI),1mg/L的Fe(II),1g/L的SA和50%的回流比。散装有机指标,包括化学需氧量,溶解的有机碳,氨,总氮,总磷,浊度,出水254nm处的紫外吸光度符合《风景环境使用水质标准》(GB/T18921-2019)。Fe(Ⅱ)的加入使得通过Fe(Ⅵ)的混凝过程产生更多的Fe(Ⅲ),产生更多质量的沉积絮体,提高了EfOM的去除效率。有机微污染物(OMPs)的去除主要是由于高铁酸盐氧化和SA在FeSDF中的吸附,大多数OMP的去除量超过90%。FeSDF中的总荧光强度去除效率为63.8%。此外,FeSDF流出物的遗传毒性降至0.73μg4-硝基喹啉-N-氧化物/L,还原效率达到97.6%。大多数指标的实际效率大于预期效率,说明FeSDF在整个过程运行过程中存在协同综合效应。
Wastewater reclamation and reuse are important methods that help to achieve an equilibrium within demand and offer, and also one of the important ways to reduce carbon emission. The existence of secondary effluent organic matter (EfOM) will bring potential threat to the environment in reuse process. Therefore, it is important to develop reclaimed water reuse technology that effectively remove EfOM. In this study, the removal of EfOM performance of ferrates enhanced by FeCl2 (Fe(VI)/Fe(II)) combined with sludge adsorbents (SAs) was evaluated by using the continuous-flow process (FeSDF), which was composed of Fe(VI)/Fe(II), SAs, densadeg and filtration. The results showed that when the inflow rate was 1 L/h, the optimal operating conditions of FeSDF including 5 mg/L of Fe(VI), 1 mg/L of Fe(II), 1 g/L of SA and 50% of the reflux ratio. Bulk organic indicators, including chemical oxygen demand, dissolved organic carbon, ammonia, total nitrogen, total phosphorus, turbidity, and ultraviolet absorbance at 254 nm in the effluent met the water quality standard for scenic environment use (GB/T 18921-2019 in China). The addition of Fe(II) makes the coagulation process by Fe(VI) produce more Fe(III) and produce more quality of sedimentary flocs and improve the removal efficiency of EfOM. The removal of organic micro-pollutants (OMPs) was mainly due to ferrate oxidation and SA adsorption in FeSDF, and the removal of most of the OMPs was more than 90%. The total fluorescence intensity removal efficiency in FeSDF was 63.8%. Moreover, the genotoxicity of the FeSDF effluent decreased to 0.73 μg 4-nitroquiniline-N-oxide/L, and the reduction efficiency reached 97.6%. The actual efficiency of most of the indicators is greater than the expected efficiency, indicating that there is a synergistic comprehensive effect during the whole process operation of FeSDF.