Effectiveness Research On Using Ultrasound Assisted Foam Copper /H₂O₂ System To Treat Dyeing Printing Wastewater

Printing and dyeing industry of our country is developing rapidly, the ability of it’s production and processing resides in the first place in the world, whatever, the emission of a large number of printing and dyeing wastewater also leads to many environment problems which can’t be ignored;have cropped up; at the same time, a large variety of dyes, process complex, resulting in printing and dyei ng wastewater is often complicated composition, high chroma, biodegradability, which belongs to the typical refractory wastewater. In view of the above situation, this paper aims to find a new pretreatment method of printing and dyeing wastewater, to remov e the color of printing and dyeing wastewater efficiently,while improving its biodegradability.Printing and dyeing industry is one of the most important economic sectiors. The wastewater from this industry has become a major source of industrial wastewater. The dyeing printing wastewater is a kind of typical recalcitrant wastewater for its high chroma and complex composition. It is necessary to find a fast and efficient pretreatment to reduce colour of wastewater, while improving its biodegradability.In this dissertation, we use ultrasound /H₂O₂ system to pretreat printing and dyeing dye wastewater.Using ultrasound /H₂O₂ system to treat dye wastewater with foam copper and ions copper as catalyst respectively. Study the effect of various parameters on the process influence on dye wasterwater treatment,obtain the optimal experimental condtions and reaction mechanism. Ultimately, better results at the wastewater pretreatment achieved. In this study, we use printing and dyeing wastewater which from a northern textile mill as research subjects.Using ultrasonic assisted foam copper /H₂O₂ system to treat rhodamine B（Rh B） wastewater found that the degradation efficiency of Rh B was significant. After the reaction of 40 min, the decolourity ratio of Rh B was 94.84% under the optimized experimental conditions. By single factor test results, we found that the degradation efficieny was influenced by many factores,such as initial p H, the dosage of H₂O₂,the dosage of ions copper and ultrasound power. By performing a radical inhibitor dosing experiments, we concluded that the the main degradation mechanism was free radical oxidation. Using TOC and UV-vis analyzing Rh B wastewater indicates Rh B was not completely mineralized to CO₂ and H₂O,instead, the chromophore in Rh B molecular structure was just destroyed underthe attack of radicals.Using ultrasonic assisted foam copper /H₂O₂ system to treat Rh B wastewater found that this system is better than ultrasonic assisted copper ions /H₂O₂ system in terms of decolorization. By performing the three factors and four levels orthogonal experiment,The reaction results in line with first-order kinetics in the optimized experimental conditions. By performing a radical inhibit or dosing experiments,the determination experiments of ? OH and H₂O₂, we found that the system Rh B degradation both rely on heterogeneous Fenton-like process occurs in copper foam surface and the ultrasonic cavitation effect reinforced by copper foam, as well as rely on the heterogeneous Fenton reaction composition support by of the small amount of ions copper dissolved from copper foam.Proing the stability of foam copper, repeatability tests and the SEM analysisare carried out, the results s how that foam copper has good physical stability and catalytic stability.The actual dye wastewater was pretreated by ultrasonic assisted foam copper /H₂O₂ system, and the effect was significant. The system can quickly remove the chroma of wastewater in a short time, so that it can reach the emission standard, at the same time, the B/C of wastewater can be increased, that is, the biodegradability of wastewater can be improved. Using GC-MS analyzing actual wastewater indicates the relative amount of macromolecule and molecule which contain chromophoric group reduced and the relative amount of micromolecule increased consistent with the chroma reduced and B/C increased.