ENVIRONMENTAL PROBLEMS CREATED BY EXHAUST EMISSION FROM IC ENGINES

The emissions exhausted into the surroundings pollute the atmosphere and cause the following problems:

1. Global warming: The earth surrounding the atmosphere contains a 3 mm-thick layer of ozone (O₃) at 50 km from its surface in stratosphere. This layer of O₃ has the specific property to absorb ultraviolet (UV) rays emitted by the sun. If UV rays enter into the atmosphere and touch the earth, they will destroy all human, animal, and crop life. It has been observed that the O₃ layer is slowly getting destroyed due to the use of chlorofluorocarbons (CFCs) refrigerants used for refrigeration and air-conditioning purposes. The CFCs have verifying degree of ozone depletion potential (GWP) as well. The use of fully CFCs that are considered to have high ODP have been banned.
2. Acid rain: The diesel engine emissions contain oxides of sulphur, SO_x (SO₂ and SO₃) in varying amounts. These emissions are dissolved in water and give rise to sulphuric acid (H₂SO₄). They fall on the earth and are very harmful to human and plant life.
3. Smog: Smog means an increase in ‘morbidity’. The increase in the levels of SO₂, SO₃, NO_x, and suspended particulate matter create huge problem in the surrounding atmosphere. SO₂ causes bronchitis spasms. SO₃ causes inflammations of the inner lining of air passages, swelling in the lining of the throat, and difficulty in breathing.
4. Odours: The members of the aldehyde family are considered responsible for the pungent odours of diesel exhaust. Even 1 ppm aldehydes in exhaust can cause irritation to the nose and eyes. The intensity of the odour is reduced by additive compounds.
5. Respiratory and other health hazards