Beijing Jingyushun Environmental Protection Co., Beijing, People's Republic of China.
State Key Lab of Environmental Aquatic Chem, Research Center for Eco-Environ. Sci., Chinese Academy of Sciences, Beijing, People's Republic of China.
Environ Technol. 2021 Sep;42(22):3432-3440. doi: 10.1080/09593330.2020.1732476. Epub 2020 Feb 28.
It is a challenging environmental issue to develop a cost-efficient approach for the removal of low-concentration refractory organics in industrial wastewater. In this study, the Fenton-coagulation process was utilised to remove the organics from the industrial effluent. The operational conditions of the Fenton-coagulation process were optimised, and then, the molecular weight (MW) and resin fraction distribution of dissolved organic matter (DOM) were investigated before and after the Fenton-coagulation process. The results showed that the efficiency of organic matter removal was affected by the Fe/HO molar ratio, pH, and reaction time. The removal rate of chemical oxygen demand (COD) by Fenton-coagulation process reached 37.8% under the following conditions: pH = 4.0 - 5.0, HO concentration = 34 mg/L, Fe/HO molar ratio = 1.5, and reaction time = 120 min. The resin fraction distribution results showed that hydrophobic bases (HoB) were almost completely removed, and the removal rate of hydrophobic acids (HoA) reached 58%, while hydrophilic matter (HiM) became the dominant form in the final effluent after the Fenton-coagulation process due to the appearance of hydrophilic charged fractions (HiC). The results were explained by a two-step mechanism (Fenton oxidation and Fe coagulation). According to the molecular weight (MW), 35.7% removal of the main fractions of organic matter with MW < 1 kDa was achieved. Furthermore, a pilot test proved that the final effluent quality after the Fenton-coagulation process conformed to the first class of the A discharge standard of pollutants for municipal wastewater treatment plants in Tianjin.
开发一种经济高效的方法来去除工业废水中低浓度难处理有机物是一个具有挑战性的环境问题。在本研究中，采用 Fenton-混凝工艺去除工业废水中的有机物。优化了 Fenton-混凝工艺的操作条件，然后研究了 Fenton-混凝前后溶解有机物（DOM）的分子量（MW）和树脂级分分布。结果表明，有机物去除效率受 Fe/HO 摩尔比、pH 值和反应时间的影响。在以下条件下，Fenton-混凝工艺对化学需氧量（COD）的去除率达到 37.8%：pH=4.0-5.0、HO 浓度=34mg/L、Fe/HO 摩尔比=1.5、反应时间=120min。树脂级分分布结果表明，疏水性碱（HoB）几乎完全去除，疏水性酸（HoA）的去除率达到 58%，而亲水性物质（HiM）在 Fenton-混凝后成为最终出水的主要形式，因为出现了亲水性带电级分（HiC）。结果通过两步机制（Fenton 氧化和 Fe 混凝）得到了解释。根据分子量（MW），MW<1kDa 的主要有机物分的去除率达到 35.7%。此外，中试证明 Fenton-混凝后出水水质符合天津市城镇污水处理厂污染物排放标准一级 A 标准。
