Research On The Technology Of Catalytic Ozonation+A/O Coupling Process Which Be Used In Treating The Wastewater From Sludge Treating Zone In The Urban Sewage Treatment Plant

Sludge treating wastewater be produced in sludge concentration, digestion anddehydration, the current treating method is making the sludge treating wastewaterreturn to the start of the sewage treatment system and being treated whith the sewage.The component of pollutants in sludge treating wastewater is very complex, nitrogencontent and organic pollution load is far higher than the sewage, there are quite anumber of refractory organics such as humus and environmental hormone.Thecircumfluence of the sludge treating wastewater may cause environmental hormoneand refractory organics penetrate the treatment system, increase the quality of treatedwastewater, so it is harmful to the safety use of reclaimed wastewater.This article used active carbon which be loaded nanoscale TiO2as catalyst in theO₃oxidation process, studied the removal of pollutants in that process, combined O₃catalytic oxidation process with A/O process and formed coupling process, probedinto the effect of lead O₃oxidation and rear O₃oxidation to the coupling process andvalued the function of O₃catalytic oxidation in the coupling process. The mainresearch conclusion as follows:As the catalyst in the O₃oxidation process, the activated carbon being loadednanoscale TiO2has strong catalysis and adsorption ability. In the presence of thecatalyst, O₃can obviously reduce the number of COD, TOC, UV254, NPnEO andTCMFP in the sewage, sludge-digestion liquid and refractory wastewater, and alsocan obviously reduce the EEMS fluorescence of DOM.Some of organic nitrogen canbe oxidated into ammonia nitrogen by O₃, at the same time,a low volume of ammonianitrogen can be oxidated into nitrate nitrogen by O₃, the O₃catalytic oxidation processcut not much ice with the concent of ammonia nitrogen and nitrate nitrogen in thethree kinds of wastewater.For actual sludge treating wastewater, A/O-Rear O₃catalytic oxidation couplingprocess is superior to lead O₃catalytic oxidation-A/O coupling process, the formercan not only avoid the interference from residual O₃molecules, but also can fullydevelop the strong oxidation of O₃, reduce the concentration of refractory organicsand environmental hormone effectively.The A/O-Rear O₃catalytic oxidation coupling process could remove thepollutants in different degrees. In this process, most of the nitrogen was removed byA/O biodegradation, but the A/O phase almost not only had no degradation to the macromolecular organic and environmental hormone, but also could not decrease thethree-dimensional fluorescence intensity of the dissolved organic matter in sludgetreating wastewater obviously. The degradation of UV254, NPnEO and DBPs wasMainly in the O₃catalytic oxidation.