Electro-flotation using in solid-liquid separation of activated sludge by orthogonal method
电解浮选用于活性污泥固液分离的正交实验研究

This research aimed to study the feasibility of using electroflotation as a substitute for traditional dissolved air flotation to activated sludge solidliquid separation.Through bench scale the research determined the appropriate operating conditions for activated sludge solidliquid separation using electroflotation.The separation of suspended solids(SS) from activated sludge was carried out in an electro-flotation cell which has two sets of electrodes,three Ti/RuO2-IrO2-TiO2 anodes and three Ti screen cathodes.The four main parameters investigated were hydraulic retention time(HRT),current density in contacting zone,current density in separating zone and electrode gap in contacting zone.Through the orthogonal method,we found out the best experimental condition of the removal ratio of SS and the current density in separating zone was the most important parameter.Under the conditions with initial SS about 1687 mg/L,HRT 25 min,current density 5 mA/cm2 in contacting zone,current density 4 mA/cm2 in separating zone,the electrode gap in contacting zone of 3 mm,the removal rate of SS can reach up to 98.9%,at this point,the electrolysis energy consumption is 0.54 kWh/m3 wastewater.