Study On The Degradation Of Phenol Wastewater By Ultrasound And Its Combined Technologies

Water pollution is a kind of environment problems all over the world and phenol wastewater is been concerned for it is toxic and difficult to be degraded.In this paper,the principle and application in wastewater treatment of ultrasonic cavitation are introduced. Then phenol which is a typification of phenolic compounds is chosen as the research object. The feasibility and influencing factors are studied in the degradation of phenolic compounds by ultrasonic cavitation,H₂O₂,Fenton reagent,CuO/H₂O₂ technology,ultraviolet catalytic oxidation and their combined technologies.The synergetic effect of each technologies are probed systematically through treating simulated wastewater of phenol.The subject intends to search a kind of disposal method which is efficacious for the disposal of this kind of contaminant and makes some bases for the treatment of industrial wastewater.So it is of great theoretical and practical values to study them in the treatment of phenol wastewater.The result shows that the degradation rate of t phenol by ultrasonic cavitation do not change much when the temperature changing from 16℃to 38℃.The degradation effect of phenol is good in acid condition,but poor in alkaline condition.The degradation rate increases when aerating to the wastewater on account of the more quantity of soluble air,the more quantity of O₂,which results in more·OH generated.The reaction mechanism of ultrasonic degradation of phenol which is approved by the influence of free radical scavenger (C₄H₉OH) is·OH oxidation.According to the regression analysis of the experiment datum, it's clear that the process of ultrasonic degradations phenol is a first-order dynamics reaction.Generally,the effects of all kinds of technologies are affected obviously by initial consistence of wastewater and the time of treatment.Except for Fenton reagent oxidation,the degradation ratios of other single technologies are very low.For example,phenol wastewater (10mg/L) can be degraded less than 10%only by ultrasonic oxidation.Under the same reaction condition,the degradation ratios of phenol have different increase in unite technologies except for US/H₂O₂ technology.US/H₂O₂/CuO technology is recommended in the treatment of phenol wastewater after discussing every combinational technology of the experiments:phenol wastewater(pH=7)can be degraded completely after 3 hours by US/H₂O₂/CuO process(CuO=100mg/L,H₂O₂=1ml/L) when the consistence is 10mg/L and it will take 6 hours when the consistence is 100mg/L.