Studies On Pre-oxidization To Enhance The Biodegradability Of The Dyestuff Wastewater

In this paper , the pre-oxidization of the dyestuff wastewater whose COD was 3500mg/I and chroma was 10000 times with Fenton reagent ,03 and UV/Ti02-Fenton respectively to enhance the biodegradability of the wastewater was studied. The effects of some factors such as pH ,temperature ,concentration of the oxidants and catalyzer on the oxidization of the organic compounds in the dyestuff wastewater by the oxidants and the interaction mechanism were also investigated. The main results are as follows:l.Influnce of initial pH The removal rates of COD and chroma of the dyestuff wastewater which was pre-oxidized by Fenton reagent is high under the condition of pH=5-7.But under the condition of alkalescence , the capacity of oxidization of 03 is strong ,and that of UV/Ti02-Fenton to wastewater dyestuff is best at pH7-9.2.lnflunce of temperature The influence of temperature on the oxidization capacity of the oxidants such as Fenton reagent and UV/Ti02-Fenton is not evident. The degradation rate of the organic pollutants by the oxidization of 03 increased with the increase of temperature..3.Influnce of concentration of oxidant The removal rate of COD of the wastewater increased with increasing concentration of Fenton reagent. However ,the high concentration of oxidants isn抰 economic. When the concentration of H202 is lml/SOml,dyestuff wastewater can be treated by biochemical method ;When the concentration of 03 is l6m3/h.m3,the removal rate of COD and chroma is high under the condition of proper pH and concentration.4.Influence of catalyzer When the wastewater is treated with Fenton reagent2+Fe2~ plays a very important role in oxidization .If the concentration of Fe is0.2-O.4ml/SOml,the catalyzing effect can be obtained ,In addition ,Ultraviolet light and Ti02 can enhance the oxidization capacity of the oxidants.5.Camparison of the oxidization capacity of Fenton reagent , 03 and UV/TiO2-Fenton indicate that the order is :UV/Ti02-Fenton>Fenton>03.6.Biodegradability of the dyestuff wastewater can be enhanced greatly through pre-oxidization with Fenton reagent , 03 and UV/Ti02-Fenton. After the wastewater was pre-oxidized with UV/Ti02-Fenton and then treated by biochemical method , the water quality can reach the first criterion ;After the wastewater was pre-oxidized with Fenton reagent and 03 and then treated by biochemical method ,the water quality can reach the second or third criterion.2Author:Yan ZhiyongDirected by: Professor Yang RenbinProfessorFang Zhi...