Emission in 2 & 4 wheeler

EVAPORATIVE CONTROL SYSTEM

As we are seeing in the image that there are two kinds of emissions:
1. Exhaust emission

2. Non exhaust emission

Exhaust emission :

All the gases through the exhaust pipe are called as exhaust emission.

 Major exhaust gases are:-

HC (hydrocarbon )
COx (carbon monoxide and dioxide )
NOx ( nitrogen oxide )
H2O (water)
And particulates matter

Non Exhaust Emission :

The emissions from the fuel tank and carburettor are know as non exhaust emission.
So to overcome this kind of pollution from the two wheeler, the technology is introduced known as BS-4 .
  In this technology the hydrocarbon emissions are controlled and decrease to 50% as they are before
  i.e. HC level decreases from 0.2g/km to 0.1g/km .
To control this emission from tank and carburetor several components are used as shown in the diagram :-

As we seen in the above diagram that there is a vapour-liquid separator in the fuel tank , which separates the fuel vapours and transfer them to canister . On the other hand fuel vapours from the carburetor are also transfer to canister. 

Canister - Canister consist of charcoal which separates the fuel particals and air, then air is passed to filter through hose pipe and the residual fuel particals are used for combustion process with the help of purge valve 

Purge valve- Its function is to transmit the fuel vapour from the canister to the combustion chamber.

When the engine sucks the charge, the inlet valve opens and sucks the fuel-air mixture , then the purge valve open by action of solenoid coil through this valve fuel vapours from the canister moves to the combustion chamber through the purge valve, so with the help of this system all the fuel vapours are utilised .


So the main purpose of BS4 technology is to reduce polution....

Thank you