The Effect On The Characteristic Of Activated Sludge By PAM Addition

The addition of polymer coagulant PAM has been an effective way to enhance particle pelletization. However, it is still unclear that whether PAM may have influence on the the characteristics of activated sludge and its biological degradation process. A laboratory experiment was thus conducted to investigate the effect of continuous PAM addition on the activated sludge using a sets of SBR reactors and application of Fluorescence In Situ Hybridization (FISH) and other microbiological techniques. The experiment concluded several stages as follows:anoxic for 167.5 min,aeration for 502.5min, sedimentation for 30min, stewing for10min.The results are as follows:(1) With PAM dosage of 3 mg/L,the continuous addition of PAM makes no difference to the growth of microorganism;(2) The PAM sedimentation in the sludge makes MLSS concertration and unit sludge biomass increase, and strengthen the sedimentation performance of activated sludge;(3) The initial stage of the PAM addition promotes the removal of organic matters and the removal of COD from 288.1mg/L to 11.9mg/L, with the sedimentation of PAM in the sludge,the extra PAM flows out with the clean upper water,the COD rises instead after 36 days;(4) As the intake load gets its steady point PAM of certain density stimulate the growth of nitrifiers and ammonia-oxidizing bacteria has incresase from 9.1×105 CFU/ml,1.8×105 CFU/ml,1.1×105 CFU/m to 1.0×106 CFU/ml,2.0×105 CFU/ml,1.2×105 CFU/ml, and the dominant colony is ammonia-oxidizing bacteria. (5) The PAM addition has no influence on the removal of phosphorus.