Air Pollution environment and disaster I.pptx

Environmental Management

1. AIR POLLUTION: Causes, effects and control Normal composition of clean air at or near sea is as follows Gases Percent (by Volume) Nitrogen 78.084 Oxygen 20.9476 Argon 0.934 Carbon dioxide 0.0314 Methane 0.0002 Hydrogen 0.00005 Other gases minute Air may get polluted by natural causes such as volcanoes, which release ash, dust, sulphur and other gases, or by human activities (emission from vehicles, industries, etc.). Any gas, liquid or solid substances are considered as a pollutant because of very large emission rates are harmful and unwanted effects . The air act defines ‘air pollution’ as the presence of any dangerous pollutant that makes the air unbreathable .

2. Depending on the form of pollutants present in the environment, they are classified as: Primary pollutant Secondary pollutant Directly emitted in the atmosphere in the harmful form. Five primary pollutants include Sulfur dioxide, Nitrogen oxide, carbon monoxide, solid or liquid particulates and particulates of lead These are formed by reacting with other components of the atmosphere to form new pollutants. Extremely small particles of solids or liquid droplets suspended in air are called particulates. A volcanic eruption releases smoke and ash which are considered primary pollutants. Secondary pollutants form when primary pollutants interact with other components to form new pollutants. For example, Sulfur oxides and nitrogen oxides react with rain water and forms sulfuric acid and nitric acid, respectively 70% of total CO emissions come from vehicles. Sulfur dioxide released in a power plant or factory from combustion of fossil fuel. Nitrogen oxides are produced by combustion of fossil fuels at high temperature. Smog, a combination of smoke and fog, result of burning coal which releases smoke and sulfur dioxide.

3. Sources of Air Pollutants: Air pollution results from gaseous emission from mainly industry, thermal power stations, automobiles, domestic combustion etc. 1. Industrial chimney wastes : The chief gases are SO2 and NOx (Oxides of Nitrogen) 2. Thermal power stations: The chief pollutants are fly ash, SO2 and hydrocarbons. The coal consumption of thermal plants is several million tones 3. Automobiles: The exhaust from vehicles produces many air pollutants including unburnt hydrocarbons, CO, Nox and lead oxides (antiknock additive) 7 oxides of nitrogen are NO, NO 2 , NO 3 , N 2 O, N 2 O 3 , N 2 O 4 and N 2 O 5 . Nitric oxide (NO) and Nitrogen dioxide (NO 2 ) are important in air pollution study 4. Particulate Matter: aggregates of small molecules

4. Effects of air pollution a)Effects on Human: Effects of sulfur dioxide, oxides of nitrogen, and ozone include eye and throat irritation, coughing and chest pain. Nitrogen dioxide is known to cause accumulation of excessive fluids in the lungs. Ozone, a highly irritating gas include dry throat, headache. Particulates are microscopic solids or liquid droplets can be inhaled and cause serious health problems . b)Effect on plants. damage the leaves, interferes with photosysthesis and plant growth, reduces nutrient uptake. leads to damage from diseases, pests, drought c)Effect on Materials: Air pollutants breakdown exterior paint, discolored the irreplaceable monuments (historic buildings) d)on Stratosphere: Ozone is continuously being created in the stratosphere by the absorption of short-wavelength UV radiation, while at the same time it is continuously being removed by various chemical reactions that convert it back to molecular oxygen Chlorine, nitrogen and bromine, which acts as catalysts, speeding up the removal process of ozone. CFCs are predominant .

5. Integrated approach for air pollution control : Air pollution can be controlled by some fundamental approaches: • Preventive techniques – reduction of pollution at source, removing sulfur from coal, Setting chambers remove the large particulates • Reducing the use of Fossil fuels – through modification of process and equipment • Improving quality of vehicular fuel – less polluting fuel like hydrogen gas • Increasing the use of renewable energy- solar energy, wind energy, planting more trees

6. The Air (Prevention And Control of Pollution ) Act,1981 In India, The Air (Prevention And Control of Pollution ) Act, has been enacted in 1981. Salient Features of The Air (Prevention And Control of Pollution ) Act, 1981 1. The Air (Prevention and Control of Pollution) Act, 1981 defines " air pollutant " as any solid, liquid or gaseous substance present in the atmosphere in such concentration as may be injurious to human beings or other living creatures or plants or property or environment. 2. The act set up the Central Pollution Control Board ( CPCB ) at the central level and State Pollution Control Boards ( SPCB ) at the state level to advise the government on any matter concerning the improvement of the quality of the air and prevention, control and abatement ( reducing/removal ) of air pollution. 3. The CPCB establish rules for the quality of air and provides technical assistance and guidance to the SPCB. 4. The function of CPCB and SPCB is to collect, compile and publish the data regarding air pollution. And also to guide the concerned industry for the effective prevention and control of air pollution. 5. CPCB and SPCB are authorized to instruct the emission standards from automobiles, restrict the activities of certain industries and declare the air pollution control areas.