Coal Forming
Ø HOW IS COAL FORMED?
Coal is a complex mixture of compounds of carbon, hydrogen, oxygen along with small amounts of nitrogen and sulphur compounds and some free carbon.
Most of our coal was formed about 300 million years ago when much of the earth was covered by steamy swamps. Eventually bacterial and chemical action at high temperature and pressure inside the earth gradually changed the materials to coal. The slow chemical process of the conversion of wood into coal by a biochemical process extending over millions of years is called carbonization.
Ø TYPES OF COAL
Coal formation is a continuing process. Depending on carbon content, moisture and volatile compounds, coal is classified into four categories: Peat, Lignite, Bituminous and Anthracite.
Type of coal
Peat(youngest variety)-light brown Lignite
Bituminous(the common variety of coal)-grey black
Anthracite(best variety of coal)hard coal
% of carbon content
50-60
Uses
60-70
70-80
In thermal power plants
Household fuel
90-95
As a reducing agent for the extraction of metals.
The different varieties of coal formed depend on how long and at what temperature and pressure the coal is buried under the surface of the earth. Peat is the most inferior quality coal and anthracite the most superior quality coal. Bituminous and anthracite are generally used fuels in industries and in our households. Peat (dead plant material)
Lignite (brown coal)
Bituminous (household soft coal)
Anthracite (hard coal)
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Uses of coal:
Coal is used as a fuel because it burns easily and has high calorific value. It is used to make other fuels like coal gas, synthetic petrol, methane and coke
Coal is used in the manufacture of industrially useful compounds like benzene, phenol, naphthalene, etc.
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Destructive Distillation of Coal:
On strong heating coal in a closed tube it breaks down into different components such as coal gas, coal tar,
Coal is a complex mixture of compounds of carbon, hydrogen, oxygen along with small amounts of nitrogen and sulphur compounds and some free carbon.
Most of our coal was formed about 300 million years ago when much of the earth was covered by steamy swamps. Eventually bacterial and chemical action at high temperature and pressure inside the earth gradually changed the materials to coal. The slow chemical process of the conversion of wood into coal by a biochemical process extending over millions of years is called carbonization.
Ø TYPES OF COAL
Coal formation is a continuing process. Depending on carbon content, moisture and volatile compounds, coal is classified into four categories: Peat, Lignite, Bituminous and Anthracite.
Type of coal
Peat(youngest variety)-light brown Lignite
Bituminous(the common variety of coal)-grey black
Anthracite(best variety of coal)hard coal
% of carbon content
50-60
Uses
60-70
70-80
In thermal power plants
Household fuel
90-95
As a reducing agent for the extraction of metals.
The different varieties of coal formed depend on how long and at what temperature and pressure the coal is buried under the surface of the earth. Peat is the most inferior quality coal and anthracite the most superior quality coal. Bituminous and anthracite are generally used fuels in industries and in our households. Peat (dead plant material)
Lignite (brown coal)
Bituminous (household soft coal)
Anthracite (hard coal)
Ø
•
va
•
a
•
b
Uses of coal:
Coal is used as a fuel because it burns easily and has high calorific value. It is used to make other fuels like coal gas, synthetic petrol, methane and coke
Coal is used in the manufacture of industrially useful compounds like benzene, phenol, naphthalene, etc.
Ø
Destructive Distillation of Coal:
On strong heating coal in a closed tube it breaks down into different components such as coal gas, coal tar,