Treatment of oil-field produced water by combined process of Anaerobic Baffled Reactor (ABR)-Biological Aerated Filter (BAF): a pilot study

Abstract

The combined process of Anaerobic Baffled Reactor (ABR) and Biological Aerated Filter (BAF) was used to treat the oil-field produced water. The experimental results showed that for ABR the removal efficiency of oil and COD was 84.5%, 40.8%, respectively, and the ratio of BOD5/COD of the effluent increased 24.8% when the flow rate was 0.3 m³/h. For the BAF, when the hydraulic loading rate was 0.6m/h and the influent COD was 203.5 mg/L, the effluent COD was 85.7 mg/L, the removal efficiency was 57.9%. The removal efficiency of Suspended Solids (SS) was 82.7%. The total removal efficiency of oil, COD, BOD and SS was 96.1-96.7, 58.2-75.1, 80.0-93.1 and 80.7-87.1%, respectively. The GC/MS analysis showed that the different components of oil could be removed by this combined process. The Scanning Electron Microscopy (SEM) observation indicated that the biofilm was dense and compact and the microbial composition was abundant and diversiform.