Sulfate-reducing anammox for sulfate and nitrogen containing wastewaters

AbstractIn a moving bed biofilm reactor (MBBR) at moderate temperature of 20°C sulfate reduction along with ammonium oxidation were established. In an upflow anaerobic sludge blanket reactor (UASBR), the same process took place at 36°C. Sulfate-reducing ammonium oxidation (SRAO) was performed using reject water as a substrate for micro-organisms and a source of , with being added as an electron acceptor. Bacterial strains belonging to the phylum Planctomycetales were detected from the biofilm of the MBBR; from the UASBR species representing phylum Verrucomicrobia were found. Average volumetric TN removal rates were 0.03 kg-N/m3/d in the MBBR and 0.04 kg-N/m3/d in the UASBR. concentrations exceeding 1000 mg/l had an inhibiting effect on the SRAO process. The stoichiometric ratio of removal was significantly higher than that expected from the extent of reduction. This phenomenon can primarily be attributed to complex interactions between nitrogen and sulfur compounds and organic matter present in the wastew...