Pollutants emission from diesel engines

Pollutants emission from diesel engines
Pollutants emission from diesel engines

We will discuss different pollutants emission from diesel engines and their impact on the environment.

Nowadays, pollution from automobiles becomes the main concern for our lovely environment. Pollutants emitted from diesel engines and petrol engines are dangerous for our environment and our precious health. Both the petrol engines and diesel engines emit pollutants in their working conditions. But the Concentration of pollutants from diesel engines and petrol engines are different. Here we are going to see the emission of different pollutants from diesel engines.

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Pollutants emission from diesel engines:

1. Hydrocarbons (HC)
2. Carbon Monoxide (CO)
3. Oxides of Nitrogen (NO2)
4. Smoke and Particulate Matter
5. Aldehydes
6. Other emissions

1. Hydrocarbons:

Hydrocarbons are the significant contributors in the diesel engines emission. Black smoke from diesel engine exhaust caused by the presence of carbon particles also known as soot in the flue gases. Soot is hazardous for the health of living animals.

2. Carbon Monoxide:

Carbon Monoxide is a presence in an exhaust of both diesel engines and gasoline/petrol engines. But the concentration of Carbon Monoxide in the diesel engines is less as compared to petrol engines. If the petrol/gasoline engine produces 5% of Carbon Monoxide, then diesel engines will produce only 2% of it.

3.Oxides of Nitrogen:

When atmospheric O2 and N2 combine inside the combustion chamber at very high temperature, it produces Oxides of Nitrogen. Diesel engines produce very high Oxides of Nitrogen during the acceleration period because temperature reaches the highest due to complete combustion of the fuel in the chamber.

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4. Smoke and Particulate Matter:

Color of exhaust smoke may be white smoke or black smoke. The presence of smoke at the exhaust contains visible products produced due to poor combustion of fuel and air. If white smoke observed in a diesel engine at cold starting and no load or low load running of the engine, it indicates piston rings of diesel engines are worn out and it needs a replacement. Black smoke in the diesel engine is caused due to incomplete combustion of fuel. The amount of black smoke is directly proportional to the load on the engine.

5. Aldehydes:

Aldehydes in diesel engines are more noticeable than gasoline/petrol engines. Aldehydes have a pungent odor in diesel.

6. Other Emissions:

Hydrogen sulphide and sulphur dioxide gases formed in diesel engines due to the burning of sulfur in the presence of diesel. Ash dust and sulphuric acid are also produced during the running of diesel engines.


In this post, we have learned about different pollutants emission from diesel engines such as hydrocarbons, carbon monoxide, and aldehydes.