Feasibility Study Of Sodium Chlorite Oxidation And Electrochemical Process Treating Dyeing Wastewater

The dyeing wastewater has the characters of high acids?high salt and high CODcr concentration,which has seriously effect on environment safety if it was discharged without proper proposal.It is necessary to be pretreatment due to the poor biodegradability of the dyeing wastewater,the advanced oxidation process(AOPs)have some characteristics of high oxidation,short reaction time and easy to operate,the advanced oxidation process(AOPs)has been more and more consideration in removing organics of waste water,which has some characteristics of easy to operate?no pollution?high flexible and economic that nowadays is the research focus in environmental science and engineering.In this research,dyeing waste was pretreated with the new oxidant chlorite and electrochemical process were researched for dyeing waste in pretreating,and the effect of different factors on the removal rate of CODcr and chroma and the oxidation mechanism.Taking the acidic wastewater of disperse dyes as the object,to utilize acid of wastewater,in dark conditions,adding sodium chlorite in the wastewater to oxidize and degrade wastewater.The results of the tests showed that the optimum conditions:reacting ten hours at room temperature,CODcr degradation up to 26%,pH<3.31,90%color removal,BOD5/CODcr up to 0.52,it have greatly improved the biodegradability of wastewater,to create the conditions for follow-up and saving costs.The results of the two-dimensional electrode electrolysis treatment of simulative dyeing wastewater was researched,the effect of different pH values on the removal rate of CODcr and chroma showed that the lower pH,the better electrolysis efficiency.The oxidation efficiency of Active chlorine was influenced by leak active chlorine and pH value,designing the new reactor to resolve the problem of leak active chlorine to circulate water and gas,which improved the oxidation efficiency of active chlorine and alleviate the rate of rising pH.Paired electrooxidation for dyeing wastewater electro-oxidation using three-dimensional electrodes,the anode generated active,the cathode generated H2O2 and Fenton reaction jointly oxidated and degraded organics in the wastewater,the results showed that the lower pH,the bigger current density,the longer electrolysis time,the better electrolysis efficiency.when flow rate 3.2L/min,current density 100 mA/cm2,8h electrolysis,CODcr degradation up to 80%,95%color removal,the organic matter of dyeing wastewater has been effectively degraded,for the engineering of processing high acid and high chlorine wastewater to provide a basis.According to parameter which was by electrolysis dyeing wastewater,the result of Paired electrooxidation and three-dimensional electrodes electrolysis treatment of direct dyeing wastewater,electrolysis twelve hours,CODcr degradation up to 49.46%,18.45%TOC removal,90%color removal.