Biodiesel production from wastewater as a source using microorganisms: A review

The depletion of fossil fuels at a fast rate have led to the problem of energy security all over the world. Therefore, a substitute of source of fuel is required to solve the energy crisis to meet the requirement of the human civilization. Biodiesel is a promising source of fuel which is produced from sources like vegetable oils, non-edible oils and some organic waste. Wastewater released from different industries contains nutrients and microorganisms which are considered to be harmful to the environment. Thus microorganisms can be utilized to convert these nutrients in wastewater such as Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), phosphates, nitrates, chlorides, sulphates, total organic carbon, suspended solids and dissolved solids. The microorganisms use these pollutants as nutrients for their growth and during the process oil is produced. The oil obtained can be subjected to transesterification to produce biodiesel. Thus the present paper reviews the wastewater released from different industries, the pollutants present in them and production of biodiesel from wastewater using different microorganisms.