Performance Prediction Modeling Of Electrocatalytic Oxidation System And Optimization Of Reactor Configuration Design

Electro-catalytic oxidation as a water treatment technology has been widelypaid close attention in refractory organics treatment for its superior characteristics.With years of development, this technology has improved treatment efficiencycontinuously, and covered various needs, but the research on low consumption ofwater treatment efficiency was always a key point. Therefore, the research on highefficiency and low consumption process has a great significance for thedevelopment of electro-catalytic oxidation. In this paper, based on the reactionmechanism of electro-catalytic oxidation and the quality and conditions ofwastewater and the principle of efficiency and low consumption, through themethod of mathematical modeling and experimental evaluation system, three coreissues was studied, including the ability of anodic oxidation and cathodicreduction performance, as well as the reactor mass transfer efficiency.Combined with the related performance parameters of anode material, theformation mechanism of·OH, the related parameters of effluent water quality andconservancy, as well as the degradation pattern of pollutants, constructed aquantitative prediction model of DSA electrode, which is on behalf of the electriccatalytic oxidation properties. Using the experimental data to modify the relatedparameters in the model and revise the uncertain factors in the reaction. Throughthe theil s Inequality Coefficients, verify the prediction value and actual value ofdifferent structure with the same material and different material of DSA electrodeperformance. Then, the performance of the electrode, which unknown materialsand structure is predicted by the model, and the effects on electric-catalyticoxidation performance of the system is discussed by different pH and COD.According to comprehensive effect of the quality and conditions ofwastewater and three kinds of basic modes of mass transfer, the COD was taken asthe index, the mass transfer effect evaluation model of electric catalytic oxidationsystem has been constructed. Meanwhile, according to the wastewater flow stateand form, the relevant parameters of the model were corrected by the experiment,using numeral correlation equation to modify and revise the prediction and actualvalue by CFD software simulation. The results showed that the model can gain agreat conclusion, the sensitivity and accuracy can meet the requirements. Masstransfer model and CFD simulation were applied to optimize the key parameters ofthe mass transfer process of the reactor. The exterior of the reactor design andconfiguration of the internal structure and other relevant details were discussed.The analysis indicated when the electrode assembly in a vertical position inside the reactor and the relative position of the inlet and outlet with a180°angle,fluid near the electrodes, especially in the electrode gap could reach the best masstransfer effect. Setting up the relative position of the inlet and outlet reasonablecan increase wastewater spoiler and reflux, while using a circular or arcuateconfiguration of the reactor for sharpening can eliminate dead zone effectively,and improve the inside mass transfer of the reactor and wastewater treatmentefficiency.Using four different materials, stainless steel, titanium plate, carbon cloth andfoam nickel as a cathode, and the chlorophenol removal, TOC removal and CODremoval, the extrusion rate of chloride and current efficiency were taken asindexes to evaluate and research the performance of cathodic reduction. Theefficient electro-catalytic oxidation system was established with the strongercathode reduction performance of titanium plate as cathode and the nano structureof Ti/RuO₂/SnO₂electrode as anode. The color, the COD removal, chlorideremoval and energy consumption were investigated to compare with the efficiencyof electrochemical degradation of Haining industrial wastewater between theoriginal and improved system. The results showed that when the wastewatertreatment time of the improved system was50min, the effluent can reach thestandard, which is10min less than the original system. At the same treatment time,the COD removal, the color removal and the chloride removal of the improvedsystem was higher than the original about4%,10degrees and4.23%respectively.Meanwhile, the energy consumption was decreased3.57kWh per kg COD.Aiming at energy-saving and cost-reducing of the system, in this paper,energy consumption analysis and evaluation model was constructed. Through theparameter analysis and model decomposition, using the COD as a bridge totransfer the relationship of energy consumption model, mass transfer model andanode model, it provided an effective method for the solution of the energyconsumption model. The model was applied to Haining of the wastewatertreatment engineering of a pharmaceutical factory, and then put forwardreasonable improvement project of reactor configuration and effective energysaving solutions, after the application, wastewater treatment of the total energyconsumption can be reduced by30.80%. This result provided reference for thereconstruction and development of the electric-catalytic oxidation in wastewatertreatment and application in the high efficiency and low energy consumption.