Abstract:

Unbiodegradable organic fraction in refinery wastewater is unable to be treated by oil separator-air floatation-biological combined process to meet the discharge standard. The catalytic oxidation-BAF combined process was utilized to treat this kind of non-biodegradable wastewater in a pilot plant. The results showed that after the waste water treated by catalytic oxidation followed by BAF treatment, the COD, NH3-N, oil and suspended solids (SS) in the effluent were 51.2 mg/L, 5.3 mg/L,2.3 mg/L and 27 mg/L, respectively, the removal rate of COD(Ave.) NH3-N(Ave.), oil(Ave.), SS(Ave.) reached to 83.1%, 80.1%, 73.4% and 61.6%, respectively. The quality of effluent meets the discharge requirement of first grade national standard. It is concluded that this combined process can be used in the existing industrial device without a need for revamping the wastewater treatment system.

Key words: catalytic oxidation, BAF, non-biodegrable wastewater, COD, NH3-N