- Carbon monoxide (SO) is the most toxic compound formed during engine operation, therefore, its content in exhaust gases is measured. During diesel operation, carbon monoxide is also produced during incomplete combustion of fuel, however, in relatively small quantities (two-thirds less than in a gasoline engine with adjusted catalytic converter!).
- Hydrocarbon is produced (CH), if the spark plug flame goes out on a cold engine. Basically, hydrocarbon is formed when the mixture is too rich or lean. Diesel produces this compound in small quantities.
- Nitrogen oxides (NOx) are formed primarily due to the fact that air consists of 3/4 of nitrogen. Their share increases significantly at high combustion temperatures at which diesel engines operate. Compared to a gasoline engine with a catalytic converter, a diesel engine produces approximately twice as much nitrogen oxides.
- Soot particles are a typical occurrence in a diesel engine due to its working principle. They consist of unburned hydrocarbons and ash. Soot formation intensifies at high engine load and low engine speeds. Dangerous is the property of soot to move hydrocarbon compounds harmful to health, in connection with which the diesel engine got its reputation as an engine with a heavy odor.
- Sulfur dioxide (SO2) formed in small quantities due to the sulfur content in diesel fuel.
Exposure to harmful substances
- Carbon monoxide is dangerous if inhaled and can cause death in an enclosed space! In air, carbon monoxide reacts relatively quickly with oxygen to form harmless carbon dioxide (CO2).
- Hydrocarbon compounds are a wide range of substances, ranging from harmless to carcinogenic compounds formed during diesel operation, which can lead to cancer. In the air, hydrocarbon compounds combine with nitrogen oxides to form smog (poorly soluble clouds of exhaust gases).
- Nitrogen oxides lead in certain concentrations to irritation of the respiratory system. When combined with water, they form nitric acid (acid rain).
- Soot particles have the unpleasant property of absorbing harmful (possibly causing cancer) hydrocarbon compounds and transfer them to the atmosphere. Hydrocarbon compounds impart a heavy odor to diesel exhaust.
- Sulfur dioxide, interacting with oxygen from the air, forms sulfuric or sulfurous acid, both types of acids are involved in the formation of acid rain. True, transport forms only 3% of sulfurous acids (SO 2).
Exhaust gas neutralization
The fuel is made up of carbon and hydrogen. When burned in an engine, carbon reacts with oxygen from the air to form carbon dioxide (CO2). Hydrogen (H), interacting with oxygen (O2), produces water vapor (H2O). About 0.9 liters of water is obtained from one liter of fuel, which is not in its usual state due to the high temperature of the exhaust gases, but exits the muffler in the form of vapors. On a cold engine, especially in the cold season, a white exhaust containing water condensate is clearly visible.
Although the diesel engine has a slightly different principle of operation from gasoline engines, it also produces harmful substances.