Study On Treatment Of Three Kinds Of Anionic Surfactants In Wastewater With MBR

In this study, the MBR was used to treat the Wastewater of surfactants and outflow was recycled.The objectives of this study are to investigate flux of gas, initial anionic surfactants concentration, the activated sludge concentration and added organic which influence the MBR treating Anionic surfactants in Wastewater. The result demonstrated that biodegradation velocity of DBS, AOS, SDS increased with a relatively low rate as the flux of gas increased. The biodegradation velocity of MBR increased with the increase of the initial concentration of DBS, AOS, SDS in a certain range. The increase of activated sludge concentration prompted the biodegradation of DBS, AOS, SDS. Various concentrations of additional organics affected the biodegradation of DBS, AOS, SDS differently. The biodegradation velocity of DBS and AOS firstly increased then decreased with the addition of organics while the biodegradation velocity of SDS kept increasing during this course.Several factors influencing the biodegradation of DBS, AOS, SDS were investigated, the optimum conditions were confirmed respectively: flux of gas=0.3 m~3/h, the activated sludge concentration=6948mg/L, additional organics=400 mg /L; flux of gas=0.3m~3/h, the activated sludge concentration=6648mg/L, additional organics=400 mg/L; flux of gas=0.3m~3/h, the activated sludge concentration= 6721 mg/L, additional organics=400 mg/L. Under these conditions, the concentration (<0.5 mg/L and <50 mg/L) of DBS, AOS, SDS and COD in the outflow water through MBR were superior to recycle water standards (0.5 mg/L and 50 mg/L) .Approaches for removal of DBS, AOS, SDS were discussed and results were obtained as follows: the main approach of removing DBS, AOS, SDS was biodegradation, biodegradation of anionic surfactants follows first-order dynamics.It was found that the bio-degradale sequence was SDS>AOS> DBS by compared the biodegradation of DBS, AOS, SDS. By microscopic observation of microorganisms in the activated sludge, toxicity of DBS, AOS, SDS affected the microorganisms in a certain degree. The sequence was DBS>SDS>AOS.