AIR POLLUTION

Air PollutionbySyed Hammad AliEnvironment Executive ZS EnvirCon. Pakistan.E-mail syedhammadali2001@yahoo.comCell No. +92-300-4300685 : 

Air PollutionbySyed Hammad AliEnvironment Executive ZS EnvirCon. Pakistan.E-mail syedhammadali2001@yahoo.comCell No. +92-300-4300685

AIR POLLUTION : 

AIR POLLUTION Any substance that adds to or subtracts from the usual constituents of air altering its physical and chemical properties sufficiently enough to produce measurable adverse effect on man, other animals, vegetation and materials can be regarded as AIR POLLUTION

CLASSIFICATION OF AIR POLLUTANTS : 

CLASSIFICATION OF AIR POLLUTANTS

CLASSIFICATION OF AIR POLLUTANTS : 

CLASSIFICATION OF AIR POLLUTANTS

PRIMARY AIR POLLUTANTS : 

PRIMARY AIR POLLUTANTS Particulate Matters Solid particles or liquid droplets (aerosols) Examples are soot, smoke, dust, asbestos fibers , pesticides, some metals (Hg, Pb, Cu and Fe) and also some biological agents like dust mites and flower pollen Diameter less than > 10mm settle out in less than a day Diameter 1mm or less suspended in air for weeks Particulate matter in lower atmosphere (troposphere) causes respiratory illness(asthma, chronic bronchitis etc. ) Particulate matter in upper atmosphere (stratosphere) alter the radiation and thermal budget of atmosphere lowering the temperature of earth’s surface

PRIMARY AIR POLLUTANTS : 

PRIMARY AIR POLLUTANTS Carbon Monoxide (CO) Incomplete combustion of fossil fuel 50% originate from automobiles Also present in cigrrate smoke Short lived in atmosphere & get oxidized to CO2 Reduces the oxygen carrying capacity of blood

PRIMARY AIR POLLUTANTS : 

PRIMARY AIR POLLUTANTS Hydrocarbons (HCs) Composed of hydrogen and carbons Produced by decomposition of organic matters and by certain types of plant (e.g. pine tree) Methane is most abundant HC evolved from soil in flooded rice fields & swamps Benzene and its derivates, formaldehyde are carcinogenic

PRIMARY AIR POLLUTANTS : 

PRIMARY AIR POLLUTANTS Sulphur Dioxide (SO2) Emitted when sulphur containing coal is burnt Ore smelters and oil refinery emit significant SO2 Causes respiratory problems High concentration is harmful for plants

PRIMARY AIR POLLUTANTS : 

PRIMARY AIR POLLUTANTS Nitrogen Oxide NO2 Formed mainly from nitrogen & oxygen Intermediate mixture of NO & NO2 Combustion of fossil fuels at high temperature in automobile engines Causes the reddish brown haze (brown air) Causes heart and lungs problems and may be carcinogenic Contribute to acid rain because water droplets to produce HNO3 an d other acids

SECONDARY AIR POLLUTANTS : 

SECONDARY AIR POLLUTANTS Photochemical Smog Formed in the traffic congested metropolitan cites where warm conditions and intense solar radiation present Composed of mainly ozone O3 , peroxyacetyl nitrate and NO2 Called brown air where solar radiation is intense In less solar radiation smog formation is incomplete air is called grey air Automobiles exhaust (contain HCs & NO)play role in formation of O3 & peroxyacetyl nitrate Damages leaves of plants, aggravate lung diseases in human and acute eye irritation

SECONDARY AIR POLLUTANTS : 

SECONDARY AIR POLLUTANTS Acid Rain In broad sense, several ways in which acid from atmosphere deposited on earth or Gases Nox, VOCs, & SO2 produced during combustion of coal and petroleum . These gases are reactive in air they oxidize to acid quickly dissolved in water and washed out to ground as ACID RAIN

TYPES OF RESPIRATORY DISEASES CAUSED BY AIR POLLUTION : 

TYPES OF RESPIRATORY DISEASES CAUSED BY AIR POLLUTION

Air pollution pie graphs- explains where each of the types of air pollution come from : 

Air pollution pie graphs- explains where each of the types of air pollution come from

Slide 14: 

National Ambient Air quality Standards (NAAQS)

METHODS TO CONTROL AIR POLLUTION : 

METHODS TO CONTROL AIR POLLUTION Arresters are used to separate particulate matters from contaminated air Cyclonic & trajectory separators used to separate out particulate matter from industrial emission with minimum moisture contents Scrubber separate clean air for both dust & gases by passing through a dry or heat packing material Filters collect extremely fine particulate matters Precipitators, electrically charging of dust particles and collecting it on a differently charged platform used for removal of gaseous pollutants Combustion, oxidisable gaseous pollutants completely burnt at high temperature (petrochemicals, fertilizers, paint and varnish industry) Absorption, gaseous pollutants are absorbed in suitable absorbent material Adsorption, toxic gases vapors inflammable compound adsorbed on large solid surface

LINES OF ATTACK TO CONTROL AIR POLLUTION : 

LINES OF ATTACK TO CONTROL AIR POLLUTION Suitable fuel selection(with low sulfur) Modification in industrial processes and/or equipment to reduce emission Correct selection of manufacturing site and zoning for industrial set up to disperse pollution sources Destroy pollutants by thermal or catalytic combustion Changing the pollutants to less toxic form Collecting pollutants by use of equipment to prevent it to escape into atmosphere Use of lead free petrol Use of CNG (compressed natural gas) Use of multipoint fuel injection engine