Developing programs to manage fats, oil, and grease (FOG) for local governments in India
Sewerage is a major source of water pollution in Indian cities. Delhi is a prime example: in 2007, of the 931 million gallons per day (MGD) of sewage generated, less than half (430 MGD) received treatment. With a treatment capacity of 665 MGD, the under?loading is indicative of a major problem with sewage collection systems, which are often poorly maintained and clogged with grease. Fats, oil, and grease (FOG) are generally present in high concentrations in wastewater from restaurants. If discharged into sewers, FOG clogs pipes, pumps, and downstream equipment, resulting in high operation and maintenance costs. If it enters the environment, FOG can rob surface waters of dissolved oxygen, leading to fish kills and eutrophication.
Managing FOG through comprehensive programs improves wastewater treatment efficiency while reducing operation and maintenance costs. FOG can also be used as a feedstock for biodiesel production. India is a net importer of crude oil to satisfy demand for diesel (estimated at five times that of gasoline). Biodiesel is generating interest as an alternative, with energy independence being the main driver. There are several existing and proposed initiatives for biodiesel production, mostly from nonedible oil crops, but biodiesel from brown grease (FOG collected in grease traps) remains a virtually untapped resource.