Effect of nitrate-N on the degradation of petroleum refinery wastewater in anoxic moving bed reactors
Degradations of phenol, sulfide and total hydrocarbons (TH) were analyzed with variation in the influent nitrate-N load in anoxic moving bed reactors. Increase in the degradation rates of phenol, sulfide, TH and COD were observed with increase in nitrate-N. Increase in nitrate-N enhanced the conversion of sulfide to sulfate and formation (%) of elemental sulfur decreased. Increase in the attached biomass and decrease in the suspended biomass was observed. Partial degradation of nitrate-N to nitrite-N was supported at higher nitrate-N loadings. Kinetics of pollutants removal revealed that degradation rate of phenol, sulfide and TH increased as nitrate-N increased.
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