Construction And Performance Evaluation Of Photocatalytic Reactor Based Double Helix And 3D Mesh Components

UV disinfection technology is widely used in the disinfection of surface water and urban domestic sewage,but the"photo-resurrection"phenomenon of microorganisms makes UV disinfection water out of potential safety hazards.The·OH generated by the photocatalytic process can not only completely sterilize and inhibit light revival,but also mineralize trace organic pollutants in the water.Therefore,installing a photocatalytic module in a UV sterilizer is a feasible way to inhibit the revival of microorganisms and remove trace organics.This study was based on the Computational Fluid Dynamics?CFD?simulation calculation in the earlier stage of the research group to identify the double helix structure,improved the anodizing method,designed a three-dimensional mesh structure component,and studied the sterilization and degradation of pollutants performance of the two components.The main research content is as follows:?1?Exploration of anodic oxidation methods for large-surface curved Ti sheets and characterization of materialsThe conventional anodizing was performed on a flat Ti piece with an area of several square centimeters.The previous work of the research group showed that the anodized large-surface curved Ti piece obtained a hybrid structure of TiO₂ nanotubes,nanowires,and holes.In order to anodize uniformly ordered TiO₂ on a large surface curved Ti plate,the effect of electrolyte composition and relative position of the electrode on the morphology of the material was explored;the titanium dioxide on the surface of the resulting material was found in HF inorganic electrolyte and NH₄F organic electrolyte.The nanotubes were relatively regular and uniform in morphology,but the mechanical strength of the resulting material in the HF inorganic electrolyte was better,and it could better prevent the photocatalytic functional layer from falling off.Therefore,in the follow-up material preparation research,the influence of the concentration of the electrolyte and the relative position of the electrode on the morphology of the resulting material was investigated.It was found that under the premise of 20V operating voltage,2cm electrode spacing and 20 min reaction time,the concentration of 0.3wt%HF electrolyte solution and the surface of the material obtained when the electrode was facing had the most regular structure of titanium dioxide nanotubes.Based on this,using a single screw stainless steel with the same pitch as the cathode and a titanium-based single screw as the anode,a double-helix photocatalytic module was made by anodizing under the above reaction parameters;the SEM results showed that the uniform and regular nanometer was loaded on the surface of the titanium-based helix.The tube;XRD results shown that the main component of this nanotube is anatase TiO₂ of101 crystal form;DRS results shown that the material has good light absorption performance in the UV band.?2?Exploration of water treatment performance of UV/double helix photocatalytic componentsAt an irradiation dose of 10.5mJ/cm²,the influent E.coli concentration was 3.80×10⁶CFU/L,and the effluent E.coli concentration of the device could meet the Class A emission standard for domestic sewage?<10³ CFU/L?.The reactivation rate of E.coli is one-thirtieth of that of the individual UV process,showing a good inhibition of photoreactivation.In the10-day continuous sterilizing experiment,the effluent effluent from the equipment with influent E.coli concentration of 10⁶-10⁸ CFU/L met the national Grade I A discharge standard for urban sewage.At the same time,the device has an obvious de-reinforcing effect on the photolytic antibiotics,and this enhanced effect is mainly due to the mineralization of photo-catalytic processes on the small-molecule organics after photolysis.?3?Exploration of water treatment performance of three-dimensional mesh photocatalytic componentsAnodizing process is used to load three-dimensionally encircling regular titanium dioxide nano photocatalytic functional layer on the wire;then,the photocatalytic functional layer screen was wound into a hollow annular screen photocatalytic component,and is combined with the UV lamp to form a Continuous water treatment device.At a dose of 21mJ/cm² UV irradiation,the device can achieve a sterilization capacity of 5.1 log₁₀,which was54.55%higher than that of the UV process alone;the device shown good sterilization stability and resistance during 240 h continuous operation experiments.The impact of the load,effluent E.coli concentration of the first-class A compliance rate of 99%,while the device of the anti-ultraviolet photolysis of antibiotics have a certain removal and enhancement effect,and this effect is mainly due to the photocatalytic process of photolysis After the mineralization of small molecules of organic matter.