Fig. 3From: Effect of carbon-to-nitrogen ratio on high-rate nitrate removal in an upflow sludge blanket reactor for polluted raw water pre-treatment applicationThe SBR profiles during SP1, SP2 and SP3. pH (a), DOC (b), NO3−-N (c) and NO2−-N (d). The suffixes “start” and “end” refer to the beginning and end of the reaction phase, respectivelyBack to article page