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What are Combustion Emissions?

Ken Black
Ken Black

Combustion emissions are those emissions that come from a process of controlled burns or explosions, most likely spurred by the burning of fossil fuels. They are considered very important and undesirable byproducts of the combustion process. The most common combustion emissions are those that include some type of carbon molecule, such as carbon monoxide or carbon dioxide. Other combustion emissions also exist, but are often overlooked because of the attention placed on carbon emissions.

Carbon dioxide often garners the majority of the headlines when it comes to emissions. The combustion process in automobile engines produces carbon dioxide, which is then released into the atmosphere. While carbon dioxide, in itself, and in manageable quantities, is helpful to the environment, too much carbon dioxide can be detrimental. This emission is considered to be a greenhouse gas, and may be responsible for much of the global warming on the planet.

The EGR valve recirculates vapors to help prevent excess nitrogen oxide, a combustion product, from being released in a car's emissions.
The EGR valve recirculates vapors to help prevent excess nitrogen oxide, a combustion product, from being released in a car's emissions.

Even more dangerous than carbon dioxide on a smaller scale is carbon monoxide. Though carbon dioxide cannot, in itself, poison people, carbon monoxide can. This combustion emission prevents critical parts of the body from getting the oxygen it needs. Therefore, those who breathe too much of this gas will eventually find themselves in a fight for survival. In most cases, this is only a problem in enclosed areas, which is why it often kills indoors or inside cars.

Combustion engines are usually powered by igniting fossil fuels.
Combustion engines are usually powered by igniting fossil fuels.

Like these past two combustion emissions, nitrogen oxide also has the potential to be a very serious problem. This is another common emission of vehicles, and is responsible for creating ozone at lower levels, which is a key ingredient in smog. Not only can smog cause an aesthetic issue, it can also be problematic for those with respiratory illnesses such as asthma. Ozone at the higher levels of the atmosphere is helpful. At the lower levels, it is a nuisance.

Car exhaust still produces a large amount of the air pollution in the U.S.
Car exhaust still produces a large amount of the air pollution in the U.S.

Combustion emissions can only happen when a burning process has taken place. At that time, molecules are turned into different forms. Thus, molecules that were in liquid form or solid and bonded to others, are eventually separated and became a gas, which is how combustion emissions are formed.

Due to the problems they can cause, efforts have been underway to try to find ways of reducing combustion emissions. Some of these methods include putting some type of scrubber on facilities that produce such emissions. While this may be helpful for some emissions, they have not yet been shown to be as effective against carbon emissions.

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    • The EGR valve recirculates vapors to help prevent excess nitrogen oxide, a combustion product, from being released in a car's emissions.
      By: Negaro Imaging
      The EGR valve recirculates vapors to help prevent excess nitrogen oxide, a combustion product, from being released in a car's emissions.
    • Combustion engines are usually powered by igniting fossil fuels.
      By: Anna Lurye
      Combustion engines are usually powered by igniting fossil fuels.
    • Car exhaust still produces a large amount of the air pollution in the U.S.
      By: Wrangler
      Car exhaust still produces a large amount of the air pollution in the U.S.