Slides in this set
Crude oil is a naturally-occurring substance found
in certain rock formations in the earth. It is a dark,
sticky liquid which is classified as a hydrocarbon.
This means, it is a compound containing carbon
and hydrogen, with or without non-metallic
elements such as oxygen and sulfur. Crude oil is
highly flammable and can be burned to create
Burning crude oil itself is of limited use. To extract
the maximum value from crude, it first needs to be
refined into petroleum products. The best-known of
these is gasoline, or petrol.…read more
The process of fractional
The components of crude oil have different boiling temperatures,
so they can be separated easily by a process called fractional
distillation. The steps of fractional distillation are as follows:
You heat the mixture of two or more substances (liquids) with
different boiling points to a high temperature.
The mixture boils, forming vapor.
The vapor enters the bottom of a long column (fractional
distillation column) that is filled with trays or plates.
The trays have many holes or bubble caps in them to allow the
vapor to pass through.
The trays increase the contact time between the vapor and the
liquids in the column.
The trays help to collect liquids that form at various heights in the
There is a temperature difference across the column (hot at the
bottom, cool at the top).
The vapor rises in the column.
As the vapor rises through the trays in the column, it cools.
When a substance in the vapor reaches a height where the
temperature of the column is equal to that substance's boiling
point, it will condense to form a liquid. (The substance with the
lowest boiling point will condense at the highest point in the
column; substances with higher boiling points will condense
lower in the column.).
The trays collect the various liquid fractions.
The collected liquid fractions may:
pass to condensers, which cool them further, and then go to
go to other areas for further chemical processing…read more