What are the main components of automobile emissions pollutants?
3 Answers
The main components of automobile emissions pollutants are as follows: 1. Hydrocarbons: Hydrocarbons in automobile exhaust are caused by incomplete combustion of fuel in the engine. According to U.S. data, in terms of hydrocarbon emission sources, on-road vehicles account for 29% of total emissions, non-road vehicles account for 18%, and other emission sources (stationary sources) account for 53%. 2. Nitrogen oxides: Under the high pressure and high temperature conditions in the automobile engine, nitrogen and oxygen in the air react to form various compounds of nitrogen and oxygen, collectively referred to as nitrogen oxides. U.S. data shows that in terms of nitrogen oxide emission sources, motor vehicles account for 49% of total emissions, power plants account for 27%, and other emission sources account for 24%. 3. Carbon monoxide: Carbon monoxide is a product of incomplete combustion of fuel in the engine. U.S. data indicates that in terms of carbon monoxide emission sources, on-road vehicles account for 51% of total emissions, non-road mobile sources account for 26%, and stationary sources account for 23%. 4. Particulate matter: Particulate matter refers to solid or liquid particles suspended in the air. Some particles have a larger diameter or are black and can be seen with the naked eye, such as the black smoke emitted from automobile exhaust pipes. There are also some particles with very small diameters that are invisible to the naked eye, and automobile exhaust mainly emits these fine particles.
What are the main components of vehicle emissions, and I pay special attention to these impacts during daily driving. Carbon monoxide is produced due to incomplete fuel combustion—it's colorless and odorless but very dangerous. With the car window open, it can silently enter the vehicle and cause dizziness or discomfort. Nitrogen oxides are even more troublesome; they mainly come from high-temperature combustion in the engine and often contribute to urban smog. I personally feel tightness in my chest and discomfort when breathing, especially on hot days. Hydrocarbons are unburned fuel molecules, emitting a strange odor, harmful to the environment and capable of causing ozone pollution. Particulate matter, especially the tiny black particles emitted by diesel vehicles, floats in the air and is difficult to clear once inhaled. Then there's carbon dioxide—while not directly toxic to humans, large emissions contribute to the greenhouse effect. Driving slower and avoiding sudden acceleration can help reduce it. Regular maintenance, such as replacing air filters or checking spark plugs, helps the engine burn fuel more completely, resulting in cleaner emissions, better fuel efficiency, and environmental benefits.
As an environmentally conscious citizen, I believe the main components of vehicle emissions include carbon monoxide, nitrogen oxides, hydrocarbons, particulate matter, and carbon dioxide. Carbon monoxide is highly harmful as it reduces oxygen delivery in the blood, and prolonged exposure may cause headaches or even more severe health issues. Nitrogen oxides directly damage the respiratory system - as someone who often goes out with children, I must be cautious since they increase asthma risks. Hydrocarbons are highly volatile, potentially carcinogenic, and contribute to smog formation, affecting living environments. Particulate matter is categorized into coarse and fine particles, with PM2.5 being particularly concerning as it can penetrate deep into the lungs and accumulate, exacerbating respiratory diseases. Although carbon dioxide isn't a direct pollutant, it's the primary driver of climate warming, and excessive driving significantly worsens it. I advocate for walking or cycling as alternatives to driving, using clean-fuel vehicles to collectively reduce pollution sources. Regular vehicle maintenance, such as ensuring catalytic converters function properly, can also effectively reduce harmful emissions.