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Petroleum is a brownish-black oily fluid that can be
found in the ground and in the sea. In its unprocessed
form, it is known as crude oil. There are many petroleum
products that are essential for our everyday life.
Fuels, like petrol for motor vehicles and kerosene for
heaters, plastic, asphalt and wax for candles are all
obtained from petroleum. The four main producers of
crude oil in the world today are the Middle East,
Russia, the United States and Venezuela. Petroleum was
formed under the ground many millions of years ago.
Plants and animals living in the sea sank to the sea bed
when they died. Their remains, mixed with sand and mud
in layered deposits, built up slowly over the years. The
combined action of heat, pressure and bacteria turned
these deposits into petroleum. The petroleum moved
slowly upwards to the porous rocks and became trapped
there. With the passage of time, land that was once
under water rose to the surface of the sea. As such,
petroleum deposits are now found on or near dry land.
Crude oil is obtained from the ground through
drilling. A drill is hung from a derrick which may be as
high as 60 meters. A derrick is a tower-like structure
which is built over an oil well to raise and lower the
drill. If the drill reaches oil-bearing rocks, the oil
may rush to the surface at great force and gush like a
fountain. However, this
seldom happens. Usually the oil rises to the surface
slowly. Sometimes, when there is no or low underground
pressure, the crude oil has to be pumped out.
Once the rude oil is obtained, it is sent to a
refinery to be processed. Pipelines carry the oil from
the oil fields to the collecting stations. Then, huge
oil tankers are used to carry the crude oil by sea to
the refineries.
At the refinery, the crude oil undergoes a basic
refinery process called distillation, which separates it
into fractions or components. Crude oil is heated to
various high temperatures during distillation. The hot
vapors rise up the fractionating tower which is more
than 30 meters high. As these vapors cool, different
fractions begin to condense and form lubricating oils,
kerosene and gasoline. Selected petroleum fractions may
be subjected to chemical processes to obtain other
products. |
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1. |
(a) Some petroleum products
are kerosene, plastic, asphalt, petrol and wax for candles.
(b) It means 'unrefined' or
'in its natural state'.
(c) The largest producers of
petroleum in the world are the Middle East, Russia, the United States
and Venezuela.
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2. |
(a) Petroleum is formed when
a combination of heat, pressure and bacteria act on the deposits of
remains of marine life, mud and sand over a long period of time.
(b) The word is 'turned'.
(c) The word is 'rose'. |
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5. |
(a) During distillation,
crude oil is separated into fractions.
(b) Crude oil is heated to high temperature during distillation. As the
heated vapor cools along the fractionating tower, different fractions
condense and form the various petroleum products such as lubricating
oils, kerosene and gasoline.
(c) The word is 'certain' or 'specific'.
(d) It means 'the preliminary stage'. |
