超声-Fenton联用技术深度处理皮革综合废水生化出水

针对皮革综合废水生化处理出水中存在COD和色度偏高等问题,提出采用超声-Fenton联用技术对生化后的皮革综合废水进行深度处理。通过单因素实验考察了超声功率、H2O2投加量、Fe2+投加量(即H2O2/Fe2+比)、溶液pH和反应时间对水样中COD和色度去除率的影响;正交实验结果表明,当溶液初始pH值为4.0时,各因素影响显著性的先后顺序为H2O2>超声功率>反应时间>Fe2+;其优化的实验条件为:H2O2为24.0 mL/L、超声功率为85 W、反应时间为45min、Fe2+为2.2 g/L,经超声-Fenton联用技术深度处理后COD的去除率可达85.4%。在最佳实验条件下,对超声-Fenton联用技术深度处理皮革综合废水生化出水的动力学研究发现,水样中的COD降解反应符合表观一级反应动力学,速率常数增强因子可达8.64,表明存在显著的协同效应。

Advanced treatment of effluent of biochemical treated tannery synthetic wastewater by ultrasound-Fenton process

The paper introduces an innovated combined processing method known as an advanced ultrasound-Fenton treating method of effluent of biochemical treated tannery synthetic wastewater, in which the COD and chroma were higher than the national discharge standard. The effects of treating factors including ultrasound power, H₂O₂ dosage, Fe²⁺ dosage(H₂O₂/Fe²⁺ dosing ratio), pH value and treating time on the removal rates of COD and chroma were investigated by the single factor method. Under the experimental condition with pH volue of 4.0, the remarkable and decreasing sequences of those treating factors were optimized by H₂O₂, ultrasound power, treating time and Fe²⁺ by the orthogonal experiment. And under the optimal conditions with H₂O₂ concentration of 24.0 mL/L,ultrasound power of 85 W,treating time of 45 min,Fe²⁺ concentration of 2.2 g/L, the removal rate of COD could reach up to 85.4% after the advanced treatment by ultrasound-Fenton process. The reaction kinetics was investigated under the optimal conditions. The results show that the degradation of COD in aqueous solution by ultrasound-Fenton was in conformity with the pseudo-first order kinetics. In addition, the kinetics enhancement factor could reach around 8.64. The degradation of COD by ultrasound-Fenton process has an obvious synergistic effect.