The process of changing raw crude oil into finished fuel begins with fractional distillation in the Crude
Units. After being heated and partially vaporized in a furnace, the crude oil is physically separated by a
fractionating tower into several "fractions" of hydrocarbons grouped according to their boiling ranges.
Some of these fractions are finished product after initial treating and blending. However, most of the crude
oil fractions require additional processing in other downstream refinery units in order for NCRA to produce
the high quality and environmentally clean fuel for today.

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