摘要
对超声波对印染废水中COD的去除效果进行了实验研究,考察了废水初始COD值、反应时间、温度、超声功率和pH值等因素的影响。结果表明,超声波对印染废水中COD有非常明显的去除效果,超声辐照120min,印染废水、1∶5和1∶2(漂炼∶印染废水)混合废水的COD去除率分别达到62.28%、77.27%和90.74%;废水的COD超声去除率随温度的升高而降低,随超声波功率的升高而增加;在pH=8.0(±0.3)时超声波降解印染废水效果达到最佳。实验还考察了几种无机盐对反应的影响,结果表明,加入KNO3、NaCl、CaCl2和FeCl3均提高了COD的去除率,特别是FeCl3,反应90min,废水的COD去除率达到99.46%,没有加无机盐时为83.33%。除盐析作用外,可能是由于FeCl3加快了HO.自由基的生成,促进了超声波对印染废水的自由基氧化作用。
The experiment study of the COD removal effect on printing and dyeing wastewater is made by the ultrasonic this paper, and the reaction parameters such as wastewater＇s initial COD, reaction time, temperature, uhrasonic＇s power and pH value are discussed as well. The results indicate that ultrasonic showed very apparent degradation effect on printing and dyeing wastewater at the ultrasonic exposure of 120 min, with the COD removal efficiency reaching 62. 28%,77.27% and 90.74% of single dyeing wastewater, 1 ： 5 and 1 ： 2 of rinsing and dyeing wastewater, respectively. The COD removal efficiency decreased with the increase in temperature, increased with an increase of the ultrasound＇s working power; and the optimum reaction pH value is about 8.0（±0.3）. In addition, the effects of several kinds of inorganic salts upon the reactions are investigated. The results indicate that the adding of certain concentration of KNO3, NaCl, CaCl2 and FeCl3 are proved to increase COD removal efficiency, especially for FeCl3, with the COD removal efficiency of 99.46% in 90 min reaction, very higher than that of 83.33% without any inorganic salts added. Except for the effect of salting out,it is likely that FeCl3 accelerates hydroxyl radical＇s generation,enhancing the oxidation effect of ultrasonic on printing and dyeing wastewater.
出处
《西安理工大学学报》
CAS
2007年第3期282-285,共4页
Journal of Xi'an University of Technology
基金
陕西省自然科学基金资助项目(2004B30)
关键词
超声波
印染废水
HO·自由基
无机盐
盐析作用
uhrasonic
printing and dyeing wastewater
hydroxyl radical
inorganic salts
salting out
