污泥活性炭处理染料废水的研究

采用污泥活性炭处理酸性品红模拟染料废水,研究了pH值、污泥活性炭投加量、温度、吸附时间等因素对染料废水的脱色率和COD去除率的影响。探讨了污泥活性炭处理染料废水的机理。实验结果表明:污泥活性炭表现出良好的吸附性能,随着酸性品红染料废水浓度的增加,脱色率先增大后减小,COD去除率的变化曲线与脱色率的曲线呈现相似的走势,但在脱色过程中,只有部分染料分子被吸附到污泥活性炭的结构中,另一部分脱色应归因于水溶液中的氢离子吸引染料分子中的碱性助色基团;随着污泥活性炭投加量的增加,脱色率逐渐增大,COD去除率一直减小;由于染料分子中的显色基团和助色基团与废水溶液中氢离子和氢氧根离子之间的相互作用,导致pH对处理效果的影响比较明显,脱色率和COD去除率均在pH为弱酸性范围内效果比较好;随水浴时间的增加,脱色率逐渐增加,COD去除率很低并一直减小;温度的升高使脱色率先增大后减小,COD去除率整体逐渐减小。通过正交试验得到最佳工艺参数为:pH值取5,水浴时间取6.5 h,水浴温度取20℃,染料废水浓度取2.5 mg/L,活性炭投加量取2.5 g,其脱色率为47.73%,COD去除率为62.62%。

Study on Treatment of Dye Wastewater by Sludge Activated Carbon

The treatment of acid fuchsin dyeing wastewater by activated carbon made from sludge was studied.The effects of pH value,the activated carbon（AC） dose,temperatures and adsorption times on the decolorization rates and chemical oxygen demand（COD） removal rates of acid fuchsin dyeing wastewater were investigated.The experimental results indicate that the decolorization rates first increased and then decreased with the increase of acid fuchsin dyeing wastewater concentrations,and the curve of COD removal rates shows a similar trend to that of the decolorization rates.However,only part of the dye molecules were adsorbed to the activated carbon made from sludge;on the other hand,the decolorization could be due to the basic groups in dyeing wastewater attracting with hydrogen ions.The decolorization rates of the acid fuchsin dyeing wastewater increased with the AC doses.But the COD removal rates reduced at the same AC dose.The interaction of the color groups and acid groups with hydrogen ions and hydroxide ions leads to better decolorization rates and COD removal rates in the weak acid.The decolorization rates increased gradually and COD removal rates was very low with the increase of water bath times.The decolorization rates first increased and then decreased with the temperatures,and COD removal rates decreased gradually.The optimal conditions are pH=5,time 6.5h,temperature 20℃,dyeing wastewater concentration 2.5 mg/L and AC dose 2.5g.The decolorization rate and COD removal rate of acid fuchsin wastewater at the condition are 47.73% and 62.62%,respectively.