An oil refinery or petroleum refinery is an industrial process plant
where crude oil is processed and refined into more useful petroleum
products, such as gasoline, diesel fuel, asphalt base, heating oil,
kerosene, and liquefied petroleum gas. Oil refineries are typically
large sprawling industrial complexes with extensive piping running
throughout, carrying streams of fluids between large chemical processing
units. In many ways, oil refineries use much of the technology of, and
can be thought of as types of chemical plants. The crude oil feedstock
has typically been processed by an oil production plant. There is
usually an oil depot (tank farm) at or near an oil refinery for storage
of bulk liquid products.
