AUTOMOBILE ENGINEERING LAB INSTRUCTION SHEET EXPERIMENT NO. 8 Aim To study and prepare report on the construction details, working principles and operation of the automotive emission / pollution control systems. Theory Labeled diagram, construction details, working principle and operation of the automotive emission / pollution control systems Introduction There are four areas in the automobile, which can emit pollutants into the atmosphere. These are, the fuel tank, carburetor, the crankcase and the exhaust system. The fuel tank and the carburetor emit fuel vapours, the crankcase gives out the partly burnt-air-fuel mixture blown off through the piston rings, while the emissions from the exhaust system include unburnt hydrocarbons, carbon monoxide, nitrogen oxides and sulphur oxides. These exhaust constituents cause many serious diseases as given in table 17.1 Obviously, the atmospheric pollution can be decreased by controlling these areas of the automobile. To do this, two different approaches have been followed 1 To reduce the formation of pollutants in the emissions by redesigning the engine ventilating system, carburetor and fuel tank. The combustion chamber, alongwith fuel system cooling system, ignition system and the exhaust system are also redesigned thus improving upon the combustion efficiency which reduces the emissions. 2. To destroy the pollutants after these have been formed. The details of both these approaches have been discussed in the following articles. S. No. Constitutent Disease 1 Carbon Monoxide (CO) Heart/Blood circulatory problems 2 Hydrocarbons (HC) Lung diseases 3 Nitrogen oxides (NOx) Asthma / Bronchitis 4 Lead (Pb) Blood Cancer 5 Suspended particulate matter (PM) Asthma / Bronchitis
