Study On The Process Of Special Vehicle Washing Wastewater Treatment

Special vehicle washing wastewater contains large amounts of pollutants, thesepollutants before the discharge if untreated, will cause serious pollution of the receivingwaters. Due to the biological toxicity and other reasons, the traditional method of ammonianitrogen and phenolin in wastewater is not satisfied.Photocatalytic oxidation is one of aneffective methods among advanced oxidation process （AOP）, for its characteristics of thatcomplete degradation of organic compounds, difficult to make a toxic intermediate productand secondary pollution. The targets of this thesis are to promote the application inwastewater by photocatalytic oxidation.In this work, in order to promote the industrial application of photocatalysis in specialvehicle washing wastewater as target,based on the typical ammonia,phenol as the processingobject, studies the influence of catalyst in the photocatalytic oxidation process dosage,reaction time, pH value, amount of aeration, reaction temperature, dosage of H₂O₂, initialconcentration of ammonia and phenol degradation rate,speculated the degradation process,and the treatment process of wastewater in the preliminary design.The main parts of this thesis are as follows:（1）For the ammonia nitrogen wastewater, using the single factor experiment, theexperiment of photocatalytic treatment. Experimental results show that, under certain reactionconditions, the photocatalytic degradation can effectively remove ammonia nitrogen in thewastewater. Under the optimal conditions, the solution of ammonia nitrogen removal rate canreach91.91%, higher treatment efficiency.（2）For the phenol wastewater, using the single factor experiment, the experiment ofphotocatalytic treatment. Experimental results show that, under certain reaction conditions,the photocatalytic degradation of phenol in wastewater can be effectively removed. Under theoptimal conditions, the solution of phenol removal rate can reach94.67%, the COD_Crremovalrate will reach93.24%, higher treatment effect.（3）By Langmuir kinetics equation of nanometer TiO₂photocatalytic oxidationdynamics analysis showed that the photocatalytic oxidation in reaction process and reactionsystem is related to the initial concentration of pollutants. In the initial reaction concentrationis lower, and the overall response meet the first order reaction; in high concentrationr, theoverall reaction is zero order reaction.（4）Based on the phenomenon of phenol wastewater in the process of degradation andthe data of the reaction, the preliminary discussion on the mechanism of photocatalyticdegradation of phenol and the degradation pathway of phenol.