UV/H2 O2法对印染废水生化出水中不同种类有机物的去除效果

采用UV/H2O2高级氧化法对印染废水生化出水的处理进行研究,探讨了不同反应时间、H2O2投加量、反应初始pH值等因素对UV254,ADMI7.6、DOC和COD去除效果的影响.结果表明,以UV254、ADMI7.6、DOC和COD的去除率为筛选依据,确定出最佳参数组合为:反应初始pH值为原水pH 7.4～8.1,H2O2投加量为4.5 mmol.L-1,紫外光照射时间为50 min,在最佳处理条件下,UV254、ADMI7.6、DOC和COD的去除率分别达到77%、94%、40%和69%.通过XAD-8/XAD-4吸附树脂联用技术将印染废水生化出水中溶解性有机物分为疏水酸、非酸疏水物质、弱疏水物质及亲水物质4类有机物,研究了UV/H2O2氧化工艺对生化出水中各种有机物及色度的去除效果.实验结果表明,对于该印染废水的生化出水,疏水性物质是引起色度的主要物质,所占比例以ADMI7.6表征时为92%,其中以非酸疏水物质的贡献最大,达到53%.UV/H2O2高级氧化法处理此水样中的弱疏水性有机物、疏水酸和非酸疏水物质均有较好的处理效果,对亲水性有机物的处理效果较差.实验表明,相对分子质量>10 000的大分子有机物对DOC和ADMI7.6的去除贡献较大,对UV254的去除贡献接近一半.

Study on Removal Effect of Different Organic Fractions from Bio-treated Effluent of Dye Wastewater by UV/H2 O2 Process

The pretreatment of bio-treated effluent of dye wastewater by UV/H2O2 process was studied.The influencing factors,such as H2O2 dosage,reaction time and pH values were evaluated for the removal efficiency of UV254,ADMI7.6,DOC and DOC of dye wastewater by UV/H2O2 process.The experimental results showed that,the optimal conditions determined were as follows: initial pH 7.4-8.1,H2O2 dosage 4.5 mmol·L-1 and UV irradiation time of 50 min.Under the optimal conditions,UV254,ADMI7.6,DOC and COD removal rate could reach 77%,94%、 40% and 69%.Removal effects of four different DOM fractions,hydrophobic acids,non-acid hydrophobics,tasnsphilics and hydrophilics separated by XAD-8 and XAD-4 resins.The experimental results show that:hydrophobic material was the main substance causing color,when it was characterized by ADMI7.6,the proportion could reach 92%,of which 53% was non-acid hydrophobics.It indicated that removal efficiencies of tasnsphilics,hydrophobic acids and non-acid hydrophobics were high through UV/H2O2 process,while hydrophilics’ efficiencies were lower.The experimental results showed that organic molecules with molecular weight over 10 000 contributed greatly to UV254,ADMI7.6 and DOC removal rate.