Pollutants types sources and uses
Generally we can say that a waste material that pollutes air, water or soil is called as pollutants.
The pollutants severity
Three factors determine the severity of a pollutant.
- It’s chemical nature.
- It’s concentration.
- It’s persistence.
These pollutants are being created and discharged to the environment by human.
The Pollutants and contaminants
As Pollutants are those substances which cause pollution while Contaminants are those substances that’s make something impure.
The pollutants in air
The pollutants in air are those harmful substances present in air .
A beneficial substance may be harmful beyond the specific concentration
Air pollutants change the weather, badly affect the human health, damage the plants and destroy building.
The pollutants in air types
Major air pollutants are classified as;
- Primary pollutants
- Secondary pollutants
Primary pollutants are the waste or exhaust products driven out because of combustion of fossil fuels and organic matter. These are oxides of sulphur (SO2 and SO3), oxides of carbon (CO2 and CO) oxides of nitrogen (NO) hydrocarbon (CH4), ammonia and compounds of fluorine.
Secondary pollutants are produced by various reactions of primary pollutants. These are sulphuric acid, carbonic acid, nitric acid, hydrofluoric acid, ozone and proxy acetyl nitrate (PAN).
Sources of air pollutants
99% of atmosphere consist of (N2) nitrogen and O2 (oxygen) gases.
Other gases are minor constituent still they can have major effects on our environment. Because atmosphere determines the environment in which we live, these minor constituents are safe upto a concentration limit. During the last 60 years in some areas this limit has been crossed considerably because of human activities.
Oxides of carbon
The following are the sources of oxides of carbon :
Volcanic eruption :
These two gases are emitted because of volcanic eruption and decomposition of organic matter naturally.
Combustion of fossil fuels :
However the major source for the emissions of these gases is combustion of fossil fuels (coal, petroleum and natural gas) . The burning of Fossil fuels in combustion engine of any type of automobile, kiln of any industry, or open air fires.
The fire of forest and burning of wood also emit CO2 and CO.