POLLUTION FROM INTERNAL COMBUSTION ENGINE

                       POLLUTION FROM I.C ENGINE

With context to environment or atmosphere we are talking about pollution caused from exhaust of internal combustion engine.These gases have adverse effect on our environment and they helps to degrade it in handsome amount.The majority which contributes to the degradation of environment is the unburned hydrocarbon emitted from exhaust of automobile.

Here is list of few pollutant which effect our society are:-

• Unburned hydrocarbon.
• Oxides of nitrogen(NOx).
• Carbon monoxide(CO).
• Carbon dioxide(CO2)-green house gas.
• Particulate matter.

There are various factors which effect the emission of these harmful gases.It depends on:-

• Operational speed of engine.
• Availability of oxygen in cylinder.
• Effect of spark advance.
• Mixture of air +fuel.

At low speed and idling condition,it is observed that emission of hydrocarbons and carbon monoxide is more.

When the percentage of air in the engine cylinder is more under high temperature,results in nitrogen combining with oxygen and forming oxides of nitrogen(NOx). High concentration of oxides of nitrogen is found in exhaust if spark advance is increased.

You would be thinking how oxide of nitrogen increases with increase in spark advance?

The answer is very simple,Spark is induced through igniter or spark plug to burn the air and fuel mixture in the cylinder.The spark should induced at correct time to burn all the fuel and air mixture.If there is an advance(before time) in introduction of spark to the fuel+air mixture then maximum portion of the fuel+air mixture will remain unburned and will directly be send to exhaust result in inefficient combustion.There is plenty of oxygen which combines with nitrogen and forms oxides of nitrogen(NOx).

METHOD TO REDUCE POLLUTION:-

• By leaned mixture of air+fuel ratio.
• Reducing ignition spark timing.
• Providing low compression ratio.