Production of biodiesel and its wastewater treatment technologies: A review

The development of technologies providing alternatives to petroleum fuel has led to the production of biodiesel fuel. This paper reviews the methods used to produce biodiesel fuel from various types of sources such as palm oil, jatropha oil, microalgae, and corn starch. It also includes a brief description of the transesterification process and the point source of biodiesel wastewater, from which it is mainly generated. Biodiesel wastewater is characterized by high contents of chemical oxygen demand (COD), biological oxygen demand (BOD5), oil, methanol, soap and glycerol. The treatments developed so far for biodiesel wastewater are also described. The authors also investigate the significance, ability and possibility of biological aerated filter (BAF) to treat biodiesel wastewater discharged from a biodiesel fuel production plant. The whole treatment; coagulation-biological aerated filter (CoBAF); involves the pre-treatment of biodiesel wastewater using coagulation followed by the treatment using BAF.