Study On Biological Process-Catalyzed Iron Inner Electrolysis Process For Treating Fine Chemical Wastewater

Iron inner electrolysis process had been used to pretreat high chroma and refractory industrial wastewater widely. Pilot-scale test was conducted on method of catalyzed iron inner electrolysis-A/O suspended carrier biofilm process for treating fine chemical wastewater, and removal effects of main pollutants were studied and analyzed. Because the particularity that the wastewater contain high-concentration solid suspended solids resulted in the formation of "scale" in the surface of iron, a new process that catalyzed iron inner electrolysis followed A/O suspended carrier biofilm process and the effluent of catalyzed iron inner electrolysis returned back to biological treatment system was developed through adjusting the coupling methods of between processes. The process not only solved the problem of "scale" which had bad impacts on removal effect, but kept all the advantages which catalyzed iron inner electrolysis improved sludge activity and sludge settleability when catalyzed iron inner electrolysis had been taken as pretreatment of biological system.The results showed that catalyzed iron inner electrolysis-A/O suspended carrier biofilm process had good effect for treating fine chemical wastewater on the condition that the hydraulic retention time of catalyzed iron inner electrolysis reactor was about 2 hours and the hydraulic retention time of biological treatment was about 26 hours. And the removal rates of chroma, COD, TP, NH₃-N, SS and BOD₅ were 65%, 75%, 90%, 51%, 95%, and 94% respectively. The catalyzed iron inner electrolysis-A/O suspended carrier biofilm process was more effective than MSBR process in wastewater treatment plant (total HRT was 29 hours). Sludge activity and sludge settleability were improved the input of Fe²⁺ and Fe³⁺ from catalyzed iron inner electrolysis and the effluent of secondary clarifier was transparent. But the "scale" resulted in the decrease of removal effect for the input of high-concentration suspended solids when catalyzed iron inner electrolysis had been taken as the pretreatment of biological system.A new process, A/O suspended carrier biofilm process was developed through adjusting the coupling methods between processes. In this process, the influent of catalyzed iron inner electrolysis was the effluent of biological system and the problem...