A Study On Treatment Of Reactive Black5Dye Wastewater By Combined Process Of Interior Microelectrolysis And Ozonation

Dye wastewater is one of the major sources of industrial effluent. It is characterized as dark color, complex composition and poor biodegradability. Conventional treatment methods, such as adsorption, chemical oxidation and biological treatment, cannot efficiently remove dyes from textile wastewater. So it is very essential and meaningful to find an effective way to treat dye wastewater.In this dissertation, Reactive Black5, a common azo dye, was selected as the research object.2.0g/L Reactive Black5solution was prepared as simulated wastewater and used for experimental study. Three methods, i.e. interior microelectolysis technology, ozonation technology and the combined technology of interior microelectrolysis and ozonation, were applied to treat the simulated wastewater, respectively. Taking decoloration rate, COD removal rate and TOC removal rate as the evaluation index of interior microelectolysis technology, the best reaction conditions and the influence level of various factors on the expeiment were determined through analyzing single factor and orthogonal experiments. Decoloration rate, COD removal rate, TOC removal rate and the acute toxcity to Daphnia magna were all evaluated in the other two technologies. In addition, technology assessment was also carried out.The main results of research were as follows:(1) For interior microelectolysis technology, the optimum reaction conditions were the volumetric ratio between iron scraps and active carbon (V(Fe)/V(C))1.0, pH2.0, aeration dosage0.6L/min and reaction time100min. And the influence level of various factors on the experiment was pH> V(Fe)/V(C)> reaction time> aeration dosage.(2) For ozonation technology, solution decoloration rate, COD and TOC removal rate increased with the reaction time increasing. However, the acute toxicity of effluents firstly increased, and then decreased with ozonation time increasing.(3) After pretreatment by interior microelectolysis technology, wastewater could be further decolorated and degraded by ozonation, and the acute toxicity was also reduced.(4) Compared with interior microelectolysis technology and ozonation technology, the combined technology of interior microelectrolysis and ozonation was more effective to decolorate and degrade simulated dye wastewater, and the effluent after combined technology showed the lowest acute toxicity.