Emission and Emission Control of vehicle, 

what is the emission, which Emission Control Measures Adopted by Government. 


What is Emission:-

The correct ratio of air and fuel for complete combustion inside an engine cylinder is 15.25: 1 This ratio leads to complete combustion inside the engine cylinder. But it is difficult to find this ratio at every speed inside the engine, due to which complete combustion does not occur and some un-burnt gases are left which are found in the atmosphere through exhaust, this is called Emission. For preventing from this emission every steps that we adopted which known as emission control that's why the topic title is emission and emission control


Type of Emission:-

Emission is of three types 

(i) Evaporative Emission. 

(ii) Exhaust Emission. 

(iii) Crank Case Emission.     

Evaporative Emission:-

25% Emission in SI Engine or Petrol Engine is due to evaporate. There are two main reasons -         

(a) Fuel Tank:-

Fuel tank holds atmospheric pressure at fuel which is 14.7 psi or 1.05 kg / cm2. Due to this pressure, the flow of fuel is kept in the system continuously, if the air vent is not kept in the fuel tank, then the fuel supply will stop and the engine will be shut down, it is in the cap of the air vent fuel tank or in the feel pipe line. Can be anywhere, it can also be called fuel tank breathing. When the pressure in the fuel tank increases, the fuel vapour escapes through the air vent and causes pollution.

Emission and emission control.

Type of emissions.

Emission Control Measures Adopted by Government

(b) Carburettor:-

Air vents are also placed in the carburettor for atmospheric pressure, they also cause pollution of fuel in the atmosphere outside and cause pollution.

Exhaust Emission:-

The exhaust exhaust in the SI engine contains hydrocarbon, carbon mono oxide, oxide of nitrogen gas, it is found in the atmosphere, this is called exhaust emission,

(a)  Effect of un burnt hydrocarbon:-

It is un burnt hydrocarbon. , Together with Nitrogen, make nitrates, which cause breathing problems and skin diseases for humans. But if this hydrocarbon goes inside the human body through inhalation, then it combines with the blood cells and reduces the blood pressure by 10 - 20%, which can also result in death of the human being. The smell of this gas is slightly sweet.

(b) Effect of carbon mono oxide:-

This gas is colourless, it is a very deadly gas, if 15 particles of carbon mono oxide are found in 10000 particles of air, then it will be difficult to breathe and if its percentage increases. If you go, then you can never start the engine in a closed place to avoid it.

(c) Effect of Nitrogen oxide:-

At low temperature this gas is made less and at higher temperature it is fine as long as it is low but in the combustion chamber when it combines with oxygen to form nitrous oxide. Which causes diseases like cough, eye effect and headache, if combined with blood cells, a person can be paralyzed.

Crank Case Emission:-

During the compression stroke, some air and fuel mixture gets into the bottom crank case or oil sump through the running clearance of the piston, it is called blow-by. Blow-by contains 70 to 80% un burnt gases and 20 to 30% burnt products and through the crank case ventilation system, these gases get rejected in the environment and cause pollution.

SI Engine Emission Control:-

The following means were applied to control the emission from SI engine-
(i) After Burner.
(ii) Exhaust Manifold Reactor.
(iii) Catalytic Converter.
(iv) Dual Catalytic Converter.
(v) Three way catalytic converter.
(vi) Thermal reactor packege.
(vii) Internal Exhaust gases re-circulation.
(viii) External Exhaust gases re-circulation.

(ix) Purge Valve and EAVP system for Evaporative emission control.
(x) PCV valve for control of Crank case emission.


Type of CI engine emission:-

CI engine also has pollution like SI engine but the quantity of Hydrocarbon and carbon mono oxide in CI engine is less but the quantity of Nitrogen oxide is more, in addition, there is two types of Emission in CI engine-

(a) Visible emission.

(b) Not visible emission. 

Visible emissions include smoke and non-visible emissions include hydrocarbon, carbon mono oxide, oxide, sulfuric oxide.

 Type of Smoke:-

1. Blue / White Smoke.
2. Black Smoke.

Causes affecting Smoke:-

1. Injection System.

2. Type of Fuel.
3. Load.
4. Engine Speed.
5. Un burnt hydrocarbon in CI engine.
6. Un burnt carbon mono oxide.
7. Un burnt Nitrogen oxide.       

Infra red absorption is used for measurement of the emissions inside the exhaust gases, which is also known as exhaust gas analysis.


Emission Control Measures Adopted by Government:-

1. PUC certificate:-

According to motor vehicle act 1995 this certificate is compulsory.

2. Staff:-

One inspector and their team detailed for check the vehicle pollution level.

3. Equipment:-

Vehicle checked by exhaust gas analyses.

4. Exhaust gas after treatment:-

Fitment of catalytic converter is compulsory in vehicle.

5. Fuel modification:-

Reduce lead in petrol and sulpher in diesel.

6. Alternate Fuel:-

Refer the use of LPG and CNG place of Petrol and Diesel.

7. Vintage of Vehicle:-

Trying to reduce of vehicle strength but its impossible.