Effect of different COD/SO₄^2- ratios in integrated A/O wastewater treatment systems on simultaneous organics and undesirable odor removal

The study of simultaneous carbon removal and deodorization is a challenge in the wastewater treatment field. A novel integrated anaerobic/aerobic reactor for simultaneous carbon removal and deodorization was developed. Results showed that when the COD/SO₄^2- ratio was 30:1, which means the SO₄^2- concentration was 133.3 mg/L, COD removal efficiency reached up to 95%. When the SO₄^2- concentration was less than 400 mg/L, the metabolic intermediates-hydrogen sulfide was removed completely, which decreased the emission of undesirable odor and achieved simultaneous carbon removal and deodorization successfully in organic wastewater treatment process. The microbiologic analysis approved that there are amount of sulfur-oxidizing bacteria contained in the sludge.