Study On Photo-catalytic Reactor Of Falling Film Optimized And Treated Coke Plant Wastewater

Because of its chemical stability, non-toxic and easily remove pollutants from air and water, Nano-TiO2 has become an ideal material to solve problems caused by energy and environment. With the combined features of super-hydrophilic photocatalyst properties and catalytic oxidation, high activity photocatalysis reactor is developed with that technology, which is expected to improve the light utilization efficiency and solving difficulties in catalyst recycling problem, so as to realize the industrialization application of photocatalytic reactor.Based on preliminary studies, we prepared the TiO2-xNx thin film by improved sol- gel method, tested structure by Uv-Vis, XPS, XRD, SEM and other. The results showed: when n-butyl titanate and cyclohexane volume ratio1:5, TiO2 reacting speed=150mm/min, TiO2 coating layer=3, urea coating layer=8, TiO2-xNx thin films the contact angle from 31°down to 12°, Hydrophilic rate constant is 0.018 , TiO2-xNx thin films possessed a certain extent of visible light hydrophilic property.With the integrated advisement about design element of photo-reactor,we designed a new l a cascade falling film reactor, the math model of a flat falling liquid film can be obtained by the research of the action of falling liquid film. Use of methylene blue degradation tested the performance of the reactor, under the best conditions the initial concentration of methylene blue 5mg/L, the best flow rate 3L/min, the film thickness of 1.016mm, the degradation rate of methylene blue nearly 50%.This paper another studied the coking wastewater with the designed independently cascade falling film photo-reactor, and studied the influence factor about removed rate of CODcr, colority and turbidity with the change of pH, use the H2O2, irradiation time and wastewater concentration. Under the optimal conditions, pH=11.0, H2O2(3%)=500ml/L l,irradiation time =6h, wastewater concentration(COD)=125mgL-1, colority, turbidity, CODcr removal rates were 17%, 57%, 45% or more respectively, the effect is obvious, Photocatalytic degradation of coking wastewater is feasible. The kinetics obey the Langmuir-Hinshelwood formula, at low concentration of solution. The reaction is pseudo first order.