Biofilm samples under different influent conditions and regulated by hydrochloric acid

The samples were taken from a bioreactor based on iron-carbon carrier. The experiment was carried out under the condition of total nitrogen concentration of ~ 50mg/L. In the stable operation stage (day 43 and day 120), samples were collected from the biofilm on iron-carbon carrier under different influent quality and hydrochloric acid regulation conditions. Biofilm samples were obtained from the biofilms at the top, middle and bottom of the mixed reactor.