Activated sludge combined with powdered activated carbon (PACT process) for the petroleum industry wastewater treatment: A review

Treatment of petroleum industry wastewater by a conventional process such as activated sludge may be hindered by the presence of recalcitrant organic compounds; therefore, tertiary treatments for wastewater polishing are required. Powdered activated carbon (PAC) adding to the activated sludge process can lead to a higher quality of treated wastewater, a more stable system and the production of reusable water. In this study, history, principles, mechanisms, and advantages of powdered activated carbon treatment (PACT) process, selection of carbon, typical configuration of a refinery wastewater treatment plant (WWTP) consisting of the PACT process, and application and/or performance of the PACT technology for the petroleum industry wastewater treatment have been reviewed. Several laboratories, pilot and full scale studies have demonstrated that PACT technology can be useful for the petroleum industry wastewater treatment. PACT process can generally be applied for the petroleum industry wastewater in those cases where stringent standards require to be met for certain contaminants.