Study On The Treatment Of Pesticide Wastewater By UV Enhanced Fe/Ce Double Loaded Fenton System

Pesticide wastewater is toxic,difficult to be biodegraded and difficult to be treated.Fenton method,as a typical advanced oxidation method,can rely on the strong oxidation of Fenton reagent to oxidize the macromolecular substances that are difficult to be degraded into small non-toxic substances,which has a better treatment effect on the industrial wastewater that is difficult to be degraded.However,in practical application,the traditional Fenton method still has some shortcomings,such as high treatment cost,narrow application range of pH value,and the treatment effect is difficult to meet the requirements.In recent years,the improvement and strengthening of Fenton method is a research direction of advanced oxidation method,in which the addition of catalyst and photocatalytic oxidation is one of the research hotspots.In this experiment,the effect and technological conditions of UV enhanced Fe/Ce dual loading Fenton system for pesticide wastewater treatment were studied,which provided technical basis for efficient treatment and practical application of pesticide wastewater.Taking the second stage pesticide wastewater of Dalian Ruize pesticide plant as the research object,the effect and process parameters of UV enhanced Fe/Ce double loaded Fenton system for pesticide wastewater treatment were studied through small-scale test.The research contents include:Fenton system,UV/Fenton system and UV/FeO_X-CeO_X-CSC Fenton system for pesticide wastewater treatment,pH value,reaction time,H₂O₂dosage and catalyst dosage and other factors of the influence and the determination of the best process parameters.Although H₂O₂ alone can produce certain treatment effect on pesticide wastewater,the degradation efficiency of organic matter is very low,all of which are less than 10%.When the pH is 4,the dosage of H₂O₂is 16ml/L,and the dosage of FeSO₄·7H₂O is 2g/L,the removal rate of COD in pesticide wastewater can reach 85.17%.UV radiation can greatly improve the treatment effect of Fenton reagent on organic pollutants.In the experiment,UV/Fenton method is used to treat pesticide wastewater.When the pH is 4,the dosage of H₂O₂is 12ml/L,the dosage times are 4,the dosage of FeSO₄·7H₂O is 1.6g/L,the power of UV lamp is 40W,and the light reaction is 60min,the removal rate of COD can reach 91.16%.Compared with the traditional Fenton method,the removal rate of COD can be achieved,It can be increased by about 6%.Adding high efficiency composite catalyst FeO_X-CeO_X-CSC in UV/Fenton process can improve the treatment effect and reduce the treatment cost.The orthogonal test results showed that when the pH was 3,the dosage of H₂O₂was 12ml/L,the dosage of FeO_X-CeO_X-CSC composite catalyst was 6g/L,and the light reaction was 45min,the reaction reached the best condition,and the COD removal rate could be as high as95.14%.Under this condition,the chroma of pesticide wastewater can be reduced from 320times to 16 times,and the chroma removal rate can reach 95%.UV/FeO_X-CeO_X-CSC Fenton system has a significant degradation effect on pesticide wastewater,and the composite catalyst FeO_X-CeO_X-CSC has a high reusability.After five times of reuse,the removal rate of COD can still reach more than 80%,which not only saves the cost of chemicals,but also overcomes the disadvantages of high sludge production in Fenton reaction to a great extent.Using UV/FeO_X-CeO_X-CSC Fenton system to treat pesticide wastewater is of great significance to reduce the pollution of pesticide wastewater to water environment.