. AKASH RAJ .AMAL RAJ.K .DON JOSEPH .JOSE CLEMENT .RENJITH M.C .SABIN MON FRANCIS AIR POLLUTION SUBMITTED BY
Pollution is an undesirable change in physical,chemical or biological characterstics of air,land or water that harmfully affected the life or create potential health hazard of living organism.
Any substance causes pollution is called pollutant.
DIFFERENT TYPES OF POLLUTION
Air pollution is the degradation of air quality and natural atmospheric conditions .
RESULTS OF AIR POLLUTION
Air pollutants cause injury to all living organisms.
They reduce growth and yield of crops.
It cause premature death of plants
Affects respiratory system of human and of animals.
PRIMARY AIR POLLUTANTS
Carbon monoxide (CO)
Volatile Organic Carbon (VOC) or Hydrocarbon (HC)
Nitrogen oxide (NO2)
1.Particulate matter It comprises of solid particles or liquid droplets small enough to remain suspended in air. Eg : smokes,dust,pesticides,pollen, fungal spores ,fibres,some metal like copper, iron etc. EFFECTS -Injurious to health -asthma,tuberculosis,bronchitis etc .
2.Carbon monoxide (CO)
This poisonous gas is formed from partial combustion of fuels, steel industry, oil refiners,cigarettesmoke etc.
CO is very harmful to living organism especially to animals.
It inhibits cellular respiration in plants.
Due to the combustion of fuels, respiration process of plants and animals etc.
The main reason for increasing global warming is due to the present of high amount of CO2.
4. Volatile Organic Carbon (VOC) or Hydrocarbon (HC)
These are compounds of hydrogen and carbon.
Hydrocarbons are formed naturally during decomposition of organic matter and certain types of trees such as pine trees.
The chief source are the motor vehicle,burning of fuels,decay of garbage etc.
5. Sulphur dioxide (SO2)
SO2 is released from the combustion of sulphur containing coal, petroleum refining, automobiles, ore smelters etc.
High amount of sulphur dioxide destroys the vegetation.
It disappearance of chlorophyll and break down of cells.
6.Nitrogen oxide (NO2)
It form during combustion of fossil fuels as high temperatures in automobile engines.
It also released from power plants.
It may cause heart or lung problems and may be carcinogenic.
Hydrogen fluoride gas is an extremely phytotoxic gas released by the heating of fluoride rocks, soils etc.
Lead is emitted by automobile exhaust and it causes long-term environmental pollution.
Continuous inhaling of air borne lead pollution caused lead poisoning.
It reduces the oxygen carrying capacity of haemoglobin in the blood.
It is formed in traffic congested metropolitan cities where warm conditions and intense solar radiations are present.
It caused by combination of smoke and fog.
It cause series of health hazards.
Damage plant as well as animal life .
As a result of burning of fossil fuels, and petroleum, large quantities of sulphur oxide and nitrogen oxides reach the atmosphere
These gases oxidise into sulphuric acid and nitric acid.
It deposits on the surface of earth either through rain.
It changes the pH of the soil
Don’t kill me
CONTROL OF AIR POLLUTION
1.Control of particulate matters
Scrubbers or arresters can be used to remove particulate matters from contaminated air.
Cyclonic separator ,which consists of a special chamber where a gas stream containing particulate matter is circulated through spiral.
Particles are centrifuged outward and collected.
Scrubbers are used to clear air for both dusts and gases by passing it through a dry or wet packing material.
2.Control of gaseous pollutants
Gaseous pollutants can be controlled by combustion ,absorption and adsorption techniques.
In combustion process, oxidisable gaseous pollutants are completely burnt at high temperature.
In absorption technique, gaseous pollutants are absorbed in suitable absorbent materials.
In adsorption technique, toxic air pollutants are adsorbed on large solid surfaces.
3.Control of automobile exhaust
Reduce the amount of uncombusted carbon and vehicles should be fitted with exhaust emission control.
It is most widely accepted method to remove 99% particulate matter present in the exhaust from a thermal power plant.
Working of electrostatic precipitator
It has electrode wires posses several 1000 volt
They produce a corona that releases electrons
Electrons then attach to dust particles giving a’-’ ve charge
Collecting plate attach the charged particles.
Velocity of air between plates are low fallen the dust
A scrubber remove SO2
Air is passed through scrubber with water or lime.
Central pollution control board (CPCB)
Particulate of size 2.5 micrometres or less in diameter are responsible for causing great harm to human health. They inhale deep into lungs and cause breathing &respiratory symptoms, irritation , inflammation and damage to lands.
1981: air (prevention &control of pollution) ace.
1987:It amend noise as a pollutant.
1986:Environment protection act.
Dear friends, The Earth in your hands. Please save her from pollutions.