Study on Catalytic Supercritical Water Oxidation Process for Treating the Perfume Wastewater

Against recalcitrant, the high cost of high concentration organic wastewater processing difficult biochemical degradation, low processing efficiency, this paper, using supercritical water oxidation technology to deal with this type of wastewater. For the study, the actual perfume wastewater to hydrogen peroxide as the oxidant, evaporation-wall reactors, supercritical water oxidation test of the non-catalytic and homogeneous catalysis. Factors on the reaction temperature, reaction pressure, residence time, and catalyst type and amount of organic spices wastewater degradation, through the analysis of the experimental data, the establishment of spices wastewater in supercritical water oxidation reaction kinetic equation; analysis presented perfume wastewater organics in supercritical water oxidation degradation pathways. Add Cu2 or after Mn2 catalyst, organic removal efficiency in supercritical water and catalyst have greatly improved, and with the improvement of the catalyst concentration, the greater the organic matter COD and TN removal. Reaches a certain removal continues to increase the catalyst concentration, the decrease in its conversion efficiency increases. Reaction temperature, pressure and reaction time have a greater impact on wastewater organics removal of COD, TN. Perfume wastewater COD, TN removal rate of over the catalyst concentration, reaction temperature and pressure increase and residence time increase. Mn2 as a catalyst, the reaction temperature of 440 ° C and pressure of 25 MPa and residence time of 50s, COD removal can reach more than 99%, showing the efficiency of the catalytic supercritical water oxidation technology. Catalytic supercritical water oxidation process for treating wastewater, is not satisfactory for the removal of nitrogen-containing organic, TN the removal efficiency of COD removal rate, and the nitrogen in the total nitrogen and not all directly converted to N2 part conversion for NH3-N, and N20, difficult to degradation NH3-N concentration of ammonia in water as the reaction temperature rose and rose through the determination of the spices wastewater organics the SCWO and cscwo emissions gas discovery of the discharge C02, CO, N2, NOx and other gases contained in the gas, C02, N2, accounted for most of, NOx, SO2 rarely. Supercritical water oxidation product of the perfume wastewater analysis by GC-MS technique to explore the path of degradation in supercritical water oxidation of organic perfume wastewater. The results indicate that perfume wastewater organics in the supercritical water oxidation process of degradation, 2,3,5 - trimethyl pyrazine, p-aminophenol to the first open loop generating a monocyclic intermediate, and then further oxidized to degrade to short chain carboxylic acids, the final path-based oxidation of C02 and H20, At the same time, there is also a lateral reaction between the intermediate product or a radical, such as coupling, hydrolysis, substituted, but these byproducts will also be benzoic acid, phenol is oxidized to the final product, CO2 and H2O. Article also perfume wastewater in supercritical water oxidation, the COD removal kinetics analysis of the experimental data, respectively perfume wastewater supercritical water oxidation reaction kinetic equation expression and reactivity and reaction level The value of the number. Perfume Wastewater activation energy: Ea = 52.36kJ.mol-1 without catalyst) 30.12kJ.mol of (Cu2 catalyst) 27.47kJ.mol-1 (Mn2 catalyst); preexponential factor A = 6.72s-1 (no catalyst), 4.61 (Cu2 catalyst), 3.92 (Mn2 catalyst); organic reactions series: 1.21 (without catalyst), 0.92 (Cu2 catalyst), 0.89 (Mn2 catalyst); oxidant series: 0.13 (no catalyst), 0.11 (Cu2 catalyst), 0.11 (Mn2 catalyst). Of organic reaction order is close to 1, the reaction order of oxygen is less than 1 and close to 0, the spices in wastewater CSCWO activation energy than the activation energy in the SCWO catalyst has an obvious role for supercritical water oxidation technology study the situation, put forward the further development of the technology needed to solve the problem, the main equipment corrosion, mineral deposition, the development of efficient catalysts.