Pollutants Removal By Combining Permanganate Composite Chemicals Preoxidation And Biofiltration In Drinking Water Treatment

In recent years, along with drinking water has been increasingly contaminated and standard of water quality improved continuously, some certain limitations in conventional process have been appeared. So, it has become a major subject of water supply industry to establish a conveninent and economical process.Lab and full-scale experiments were conducted to study removal efficiency and characteristic of permanganate composite chemicals (PPC) preoxidation process. Compared with the conventional process, permanganate composite chemicals preoxidation process enhanced the removal of turbidity, organic pollutants, iron and manganese, the removal of CODMn was 50.7%, 14.9% higher than conventional process; the removal of Fe and Mn are 73.15% and 62.24%, 31.24% and 43.36% higher than conventional process.Secondly, pilot dynamic experiments were conduct to study the effectivness of the biological filters which filled with five different medias. The results showed that the effectiveness and characteristic of biological filters were varied with medias. The effectiveness of biological activated carbon was the best, the results showed that, while the ammonia nitrogen of influent was about 1.6mg/L, the removal of ammonia was 94.6%, and the removal of CODMn was 28.2%. Furthermore, several factors affecting biofiltration process had been investigated in this paper, they are organic loading, anmmonia nitrogen loading, EBCT , media size, backwashing and , etc. The results showed that the effects of organic loading, anmmonia nitrogen loading, EBCT were due to dissolved oxygen (DO), that was to say the effect of DO was large, under our realizable conditions(influent DO was 6~7mg/L), the maximum of NH4+-N removal was about 1.6mg/L.On the basis of study on the effectiveness and characteristic of permanganate composite chemicals preoxidation and biofiltration process respectively, the effectiveness and mechanism of pollutants removal for combined process of permanganate composite chemicals preoxidation and biofiltration was studied by pilot dynamic experiment. The results showed that the influent DO and the microbial activity were increased by permanganate composite chemicals preoxidation, thus the effectivness of biofiltration process on revmoving organic pollutants and...