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Chapter 3 . Refining Oil (Downstream)
Prof.Riggs
SEPARATION
In this phase, a refinery heats crude
oil to different temperature levels. Different
parts of crude oil have different boiling points. As
the temperature rises, these different parts or
fractions are separated. This is done inside
distillation towers.
The lightest fractions,
which include gasoline and Liquefied
Petroleum Gas (LPG), vaporize quickly and rise
to the top of the distillation towers. There
they condense back into liquids.
The medium-weight
fractions, which include kerosene and
diesel oil distillates condense in the middle
of the distillation tower.
The heaviest liquids
(called residual oils) have the highest
boiling points and leave through the
bottom of the distillation tower.
Refineries also
use chemical agents called
CATALYSTS
. These help refine oil
further by either removing carbon
or adding hydrogen.
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