Study On Decolorization And Biodegradability Of Wastewater Promoted By Zero-valent Iron

Based on the principle of degradation of organic matter by galvanic cells formed by iron filings,this study can realize the processes of reduction,adsorption,flocculation and oxidation of organic matter under different conditions.In the first chapter,the removal rate and degradation products of iron filings from azo dye wastewater were investigated by using reactive brilliant red X-3B（X-3B）as the model pollutant.The results show that the decolorization rate of the dye can reach92.33%,and the effect is the best.The removal rate of chromaticity of the fillers with three iron copper ratios（1:0,4:1,8:1）was about 92%.The decolorization rule of the zero-valent iron system with and without N₂ was more consistent with the first-order kinetic model.The decolorization of the dye occurred in the whole reaction process,while the removal of TOC mainly occurred in the first 30 minutes.The removal rate of TOC in the system was 1/3 of the decolorization rate.Iron filings can be reused for4 times,the decolorization rate can still reach more than 90%,and the adsorption amount of iron filings is about 6%of the dye.The degradation products of X-3B were mainly long-chain alkanes,aromatics,cycloalkanes and long-chain mono-alcohols determined by full-wavelength scanning and GC-MS experiment.The degradation paths in the system were mainly reduction,followed by adsorption and oxidation.The decolorization experiment of municipal sewage by catalytic ferroelectrolysis was studied.Pretreatment experiments of chromaticity removal were carried out respectively.And explore different proportions of iron and copper filler（1:0,4:1,8:1,12:1）wastewater treatment,the percentage of 12:1 packing wastewater treatment,the12 days of running time,water color can be maintained under 10,iron and copper quality ratio of 4:1,the biggest water NO₃^-reduction,TN removal rate can reach more than 6%³3%.In engineering application,the quality of copper chips can be appropriately increased and the content of NO₃^-can be reduced.The changes of NO₃^-、NH₄⁺、NO₂^-、TN、DO、ORP and TFe are mainly related to the running time of the device and the proportion of iron and copper.The feasibility of engineering treatment of domestic sewage biochemical effluent chromaticity was discussed.To study the effect of catalytic ferroelectrolysis on enhancing the natural aerobic biochemical effluent biochemical properties of cuhk.The results showed that the chromaticity of wastewater decreased from 3000 to about 900 and the COD decreased from 460mg/L to about 284mg/L.Under micro-oxygen condition,the chromaticity of wastewater can only be reduced to about 1300,and the COD value can only be reduced to about 350 mg/L.After biochemical treatment of the column effluent,COD was reduced by about 97mg/l.The chromaticity of wastewater increases.In the continuous flow experiment,the COD of natural pigment wastewater was reduced to less than 180 mg/L,and the chroma of biochemical effluent was about 1200,which was about 50 higher than that of filler effluent.