Study on the treatment characteristics of sebacic acid wastewater by micro-oxygen biochemical and biological contact oxidation

Abstract

Sebacic acid wastewater is a typical industrial wastewater that is difficult to degrade, and the high sulfate rich in sebacic acid water is easy to be reduced to hydrogen sulfide release, leading to environmental pollution. The micro-oxygen biochemical coupling biological contact oxidation process was applied to treat sebacic acid wastewater, and the treatment characteristics of refractory industrial wastewater was investigated. The results showed that when the influent load gradually tended to be stable with COD of 4 500-5 500 mg/L and volatile phenol of 150-200 mg/L, the effluent COD was less than 400 mg/L and the volatile phenol was less than 0.5 mg/L after treating by micro-oxygen biochemical and biological contact oxidation process. The mass concentration of sulfide in effluent was lower than 0.2 mg/L, indicating that H2S was not easily produced in micro-oxygen biochemical and biological contact oxidation process. During the construction and start-up stage of the micro-oxygen section, the turbidity of the effluent decreased with the increase of DO concentration. The turbidity removal rate of the system was maintained between 70% and 90% when the overall process ran continuously and stably, indicating that the overall process played an important role in reducing the turbidity of the effluent. MLSS of 6 000-8 000 mg/L and SVI of 100-150 mL/g in the system indicated that sludge settling ability was good. The stability evaluation of the system showed that the system had strong ability to withstand load shock and salinity change, it could be widely used in the treatment of refractory industrial wastewater.

Keywords

• sebacic acid wastewater
• micro-oxygen biochemistry
• biological contact oxidation
• sulfide
• load impact resistance
• resistance to salinity change