LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465, Porto, Portugal.
Environ Sci Pollut Res Int. 2021 Feb;28(6):6437-6449. doi: 10.1007/s11356-020-10741-z. Epub 2020 Sep 30.
The present study assesses the treatability of a real industrial wastewater (WW) with a high organic load (chemical oxygen demand (COD) above 5800 mgO L) by photo-Fenton's oxidation with the goal of improving the organic matter degradation reached previously, in another work, where the Fenton process was applied in a bubbling reactor. Thus, the process was carried out in a bubble photo reactor (BPR) wherein continuous air supply ensures an efficient mixing of the liquid phase. The effect of the main operatory parameters that influence the WW treatment (i.e., HO and Fe concentrations, initial pH, and UV-Vis radiation intensity) were evaluated, being found that in the best conditions tested (pH = 4.6, [Fe] = 0.1 g L, [HO] = 18 g L, Q = 1.0 L min-measured at room temperature and atmospheric pressure-and irradiance of 500 W m), removals of 95% and 97% for total organic carbon (TOC) and COD, respectively, were achieved. Still, a high reduction of the concentration of the main constituents of this WW was reached, being total for aniline and 86% for sulfanilic acid. The continuous air supply reactor configuration was compared with magnetic stirring; similar mineralization was achieved. However, the air bubbling promotes a good heat transfer within the reactor, minimizing temperature gradients, which is quite advantageous due to the strong exothermicity of the oxidation process during the treatment of such highly loaded real effluents.
本研究评估了一种高有机负荷（化学需氧量（COD）高于 5800mgO L）实际工业废水（WW）的可处理性，目的是改善之前在另一项工作中应用芬顿工艺的鼓泡反应器中达到的有机物降解程度。因此，该过程在鼓泡光反应器（BPR）中进行，其中连续供气确保液相的有效混合。评估了影响 WW 处理的主要操作参数（即 HO 和 Fe 浓度、初始 pH 值和 UV-Vis 辐射强度）的影响，结果发现，在所测试的最佳条件下（pH = 4.6、[Fe] = 0.1 g L、[HO] = 18 g L、Q = 1.0 L min-在室温下和大气压力下测量，辐射强度为 500 W m），TOC 和 COD 的去除率分别达到 95%和 97%。尽管如此，仍达到了这种 WW 主要成分浓度的高度降低，苯胺的总去除率为 86%，磺胺酸的总去除率为 86%。连续供气反应器构型与磁力搅拌进行了比较，实现了类似的矿化。然而，空气鼓泡促进了反应器内的良好传热，最小化了温度梯度，这在处理此类高负荷实际废水时由于氧化过程的强烈放热而非常有利。
