紫外-Fenton法处理高盐有机废水

以某电镀厂水回用系统产生的高盐有机废水为对象,对比研究了Fenton、UV-Fenton等工艺去除COD性能,考察了初始pH、H2O2投加量、Fe2+与H2O2摩尔比、反应时间等参数对处理效果的影响。结果表明:UV-Fenton工艺的最佳条件为初始pH=3.0,H2O2的投加量3 mmol/L,RFe2+:H2O2=1:1,反应时间30 min;在此条件下,COD去除率可达到60%以上,分别较Fenton和UV-H2O2工艺提高23.0%和39.3%。UV-Fenton工艺中,Fenton与UV表现出良好的协同效果,其处理效果较单独Fenton和单独UV处理效果之和高14.7%。UV的引入促进Fe(II)/Fe(Ⅲ)循环,可以提高·OH生成量以及Fe2+与H2O2利用率。UV-Fenton是处理高盐有机废水的可行工艺之一。

Treatment of high-salinity organic wastewater by ultraviolet-Fenton process

This study focused on the high-salinity organic wastewater from the recycling system of an electroplating factory and compared the chemical oxygen demand (COD) removal efficiency among various treatment processes including Fenton and UV-Fenton technologies. The effects of initial pH, hydrogen peroxide (H2O2) dosage, the molar ratios of iron (Fe2+)/H2O2 (RFe2+:H2O2), and reaction time on COD removal were investigated, and results indicated that the UV-Fenton process achieved the optimum COD removal of above 60% at an initial pH of 3.0, H2O2 dose of 3 mmol/L, and RFe2+:H2O2 of 1:1 after a 30 min contact time. These results were 23.0% and 39.3% higher than those achieved by Fenton and UV-H2O2 processes, respectively. Moreover, UV and Fenton show synergistic effects towards COD removal, and the removal efficiency was 14.7% higher than the summative value achieved by UV and Fenton processes, respectively. Meanwhile, UV promotes hydroxide (·OH) production and the utilization of Fe2+ and H2O2, owing to the accelerated transformation cycles between Fe(II) and Fe(Ⅲ) species. The UV-Fenton process is particularly valuable in the treatment of high-salinity organic wastewater.