Full-scale study on effects of pre-ozonation on disinfection by-products

A full-scale study was done on the processes of pre-ozonation and a combination disinfection of ultraviolet and chlorine to treat the Luan River raw water in high temperature and high algae concentration phase.Through the testing and analyzing of the trihalomethanes formation potential(THMFP) and haloacetic acids formation potential(HAAFP) variances,the whole set of water treatment process was studied,especially the effects of pre-ozonation on disinfection by-products(DBPs) removal.At the same time,the formation of formaldehyde and bromated in treatment process was also studied.The results showed: during high temperature and high algae concentration period,the average removal rates of THMFP and HAAFP by pre-ozonation were 12.43% and 15.06% respectively,and the removal rates of combined process were 39.33% and 54.12% respectively,which meant the precursors of DBPs were removed effectively;formaldehyde and bromate in effluent were less than 50 μg/L and 6 μg/L respectively,which meant the DBPs were also controlled effectively.