Study on the Way of Urea Removal by BAF

Biofilm process is a kind of efficient way for sewage with high concentration of urea. A lot of researches on removal efficiency were carried out, but there existed less research for the process of urea removal. To understand the way of urea removal by biofilm process, biological aerated filter (BAF) was used to deal with sewage with high concentration of urea from a chemical plant, by studying adsorption property of the carrier, biomass and biological activity on the carrier, and contrastive analysis between hydrolysis product of urea and theoretical value was carried out and the microbial flora of urea removal was preliminarily determined using the method of inhibiting biological activity. The results showed that, removal of urea by BAF was mainly the result of biological action, the adsorption capacity of activated carbon for urea was limited, the dominant bacterial communities for the hydrolysis of urea were heterotrophic bacteria, and parts of nitrosobacteria and nitrobacteria also had a certain capacity of hydrolyzing urea

YAN LILONG, LI WEIGUANG, REN YUAN, LIU YU, ZHANG YING