Childrens Illustrated Encyclopedia

Burning gas to make heat is a quick and easy way to warm

the home and to cook. gas is also used in industry, both for heat

and as a raw material. most of the gas we use for fuel is natural

gas. it is extracted from deposits buried deep underground

or under the seabed. gas for burning can also be made by

processing coal to produce coal gas. these fuel gases

are not the only kinds of gas: there are many

others with different uses. For instance,

the air we breathe is made up of

several gases mixed together.

Huge drills on a production

platform sink wells to reach

gas deposits,

which lie as deep

as 4 miles (6 km)

below the seabed.

Gas

1

in the sea, tiny plants sink and

a layer of dead plants builds up

on the seabed. the sea plants

are buried in mud.

2

on land, too,

mud covers

dead plants and trees.

slowly, the mud hardens

into rock. more layers of

rock form above and press

down on the plants, burying

them deeper and heating them up.

5

raw gas has to

be cleaned and

dried before it can

be used. the gas

terminal removes

impurities

and water.

UsefUl gases

gas wells produce several different kinds of gas. methane is the

main component, but other fuel gases, called propane and

butane, also come from gas deposits. the gas terminal stores

these gases in metal cylinders for use in houses

where there is no gas connection. gas deposits

are also a source of helium. helium is used to fill

balloons because it is very light and does not burn. air

is another source of useful gases. Carbon dioxide, the gas

that makes the bubbles in carbonated drinks, comes

from air. air also contains a little neon gas. some

advertising signs are glass tubes filled with neon.

the gas glows when electricity passes through it.

gas delivery

natural gas is piped

to homes for use

in stoves and

heaters. gas stored

in metal bottles

supplies homes that

are not connected

to the pipeline.

Formation oF

natural gas

the natural gas we use

today is millions of years

old. it was formed from

the remains of prehistoric

plants that lived

on land and in

the sea. new gas

deposits are still

being created.

3

the pressure and heat slowly

change the sea plants into oil and then

into gas. land plants turn first to coal before

becoming oil and gas. a layer of rock now traps the

gas in a deep deposit. earth movements may have

raised the rocks containing the gas above sea level,

so that the gas now lies under the land.

gas For industry

not all gas is used in the

home. many power stations

burn gas to generate

electricity. in dry places,

such as deserts, the heat from burning gas is used

to process seawater in order to produce salt-free

drinking water. gas is also used as a fuel in factories

producing all kinds of things, from roasted peanuts

to cars. Chemicals made from gas are vital

ingredients in the manufacture of plastics, fertilizers,

paints, synthetic fiber, and many other products.

4

gas flows up the well to

the production platform,

and a pipeline takes it to a

terminal on land. gas from

inland wells flows straight to

the terminal.

6

gas flows from terminals to large tanks,

where it may be frozen and stored as a

liquid. the gas can also be stored in huge

underground caverns. Pumps push gas

along pipes to the places where it

is needed.

A gas layer

often forms

above a layer

of oil.

The pressure of the

gas helps force the

oil up wells to the

production platform.

Gas deposit

Oil deposit

Gas

storage

tank

Find out more

Coal

heat

oil

oxygen

science

228

Neon

sign

Helium gas

balloons

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