Study On Magnetic Activated Sludge Combined With Electrochemical Oxidation For Treating Dying Sewage

The water is the foundational natural resource and the strategic economical resources,water resource shortage and pollution are serious in China. How to cost-effectively solvesewage treatment technology is the urgent problem. Taking about printing and dyingwastewater as our objects，the treatment of dying wastewater using magnetic activatedsludge（MAS） has been studied. electrochemical oxidation Process（EOP） as the postprocessing technique，a home-designed MAS-EOP has been used to treat Reactive lightyellow X-6G sewage, and good effect has been achieved.The MAS reactor was designed and made independently. The treatment of reactivelight yellow X-6G sewage under aerobic conditions has been studied. COD of the effluentwas reduced from1600mg/L to212mg/L, the removal efficiency of COD was about87%.The dye concentration of effluent was decreased from50mg/L to23mg/L. MLVSS of theMAS reactor was increased to11000mg/L and kept stable. The addition of poly aluminumchloride （PAC） could reduce SS of the effluent and enhance sludge settling performance.And the longer the hydraulic retention time （HRT）, the better water quality of the effluent.A PEG modified Ti/Sb-SnO₂/Bi-PbO₂electrode was prepared and used in the EOPdevice.The decoloring rate of the seaage by the EOP was significantly faster in NaClsupporting electrolyte than that in Na2SO4supporting electrolyte,and the greater CODvalue of the sewage, the lower decoloring rate. When the home-designed MAS-EOP wasoperated intermittently under the conditions of that HRT of the MAS24h and the voltageof5V, the color and SS of the effluent were completely removed and COD was below100mg/L.When MAS-EOP was operated continuously, the optimum condition was thatconcentration of NaCl was0.1mol/L and the voltage was6V. These results indicatedMAS-EOP was a cost-effective treatment technique on dying wastewater, and it deservedfurther study and practical application...