Dye Wastewater Treatment Process Of The Pilot Study

Dyestuff wastewater is one matter of regional water pollution sources.In general, conventional biological treatment processes to accord with the effluent standard have some difficulties in degrading heavy chemicals with complicated components,high concentration of chemical oxygen demand,high color and characterized by inhibitor or toxic action of microorganism.Manifold treatment facilities have been developed in dyestuff wastewater at the moment,maily to remove the pollutants. As a result of various limitations, those means have great difficulties in the practical application to attain treatment benefit or cost. Facing those problems,in this study, make some concrete analyses of certain issues. All things considered,the effluent wastewater from production of dyestuff is treated with neutralization — catalytic oxidation — SBR biochemical oxidation;the dyestuff sludge consists of oxidation by hydrogen peroxide solution and oxygenated canal p'rocess.Pilot experiments are performed to confirm the optimum running conditions of each stage, the relation between some factors and the effect of treatment is analysed.Finally the treatment techniques of wastewater and slag are initially projected.During the catalytic oxidation of dyestuff wastewater, actived carbon macerated by wastewater of copper smeltery is used as solid catalysis ,chlorine dioxide and oxygen of air as liquid and gas catalysis, respectively.The result of lab scale experiments state clearly:the better treatment effect is achived when the consume of chlorine dioxide is 500mg ? L^-1 or so,pH of inlet is 4, spray density is more than 10 15m³ ? m^-2 ? h^-1, retention period is 10 25min. After dealt with the means, the COD of wastewater decreases from 1550²100mg ? L^-1 to 625⁸50mg ? L^-1, the efficieny of removal abtains over 57%, BOD₅/COD ratio increases from 0.22 to more than0.35, which improve the biochemical properties of the wastewater.When the wastewater is diposed of biochemical oxidation, we find SBR of fluidics is more effective than any other means.The COD of effluent by biochemical oxidation can attain below 200mg -I/1.After oxidized by hydrogen peroxide solution and later in oxygenated canal, the COD of sludge decreases from 4000⁵100mg ? I/1 to 330 460mg ? L"1, the toxicity of slag reduced greatly. The technological process cut down final slag by 85%⁹O% according to conventional processes. However,to avoid incomplete combustion and ensure safety.Finally the initial design of wastewater and sludge technology process is presented,the primary cost appraisal of technological process suggests that design is feasible both economically and technical1y.To spread and establish the technological process more widely, basic researches with demonstrative plants must be conducted with regard to those techniques that are capable of handling wastewater and sludge form dyestuffs.