Fig. 4From: Effect of carbon-to-nitrogen ratio on high-rate nitrate removal in an upflow sludge blanket reactor for polluted raw water pre-treatment applicationThe USB reactor profiles during UP1 and UP2. pH (a), DOC (b), NO3−-N (c) and NO2−-N (d). The abbreviations “Inf” and “Eff” stand for influent and effluent, respectivelyBack to article page