Effects of Pre-Ozonation on Organic Matter Coagulation
臭氧对有机物混凝的影响

PDA(Photometric Disperse Analysis),apparent molecular distribution and fractionation of aquatic organic matters were performed.Formation and performance of flocs in coagulation processes were detected.And changes of aquatic organic molecular structure resulted from the influence of pre-ozonation were studied.Complicated effects of O3 on organic matter coagulations were showed;dosage of O3 and characteristics of aquatic organic matter were two of the major factors result in whole performance of O3 on coagulation.Judged from results of fractionation,great influence was made by O3,which increased fraction of more polarity and hydrophilic by 36.7% and fraction of molecule smaller than 10×103 by 100% or so;but total removal of DOC was limited only 3.28%.When PACl was used as coagulant,less effect on floc formation was observed as O3/TOC<0.7.With O3 dosage increasing,floc formation was retarded more and more and removals of turbidity,DOC and UV254 were all decreased.AlCl3 performed badly than PACl under influence of O3 in almost all the parameters detected in the study.It showed that PACl was superior to AlCl3 when pre-ozonation were adopted.