The pollutants emitted by automobiles mainly include HC (hydrocarbons), nitrogen oxides (nitrogen oxides), CO (carbon monoxide) and PM (particulate matter). Through the application of better catalytic converter active layer, secondary air injection and exhaust gas recirculation system with cooling device, the pollutants emitted by automobiles can be controlled and reduced to below the specified value.
Extended data:
Automobile emission refers to harmful gases such as CO (carbon monoxide), HC+ nitrogen oxides (hydrocarbons and nitrogen oxides) and PM (particulate matter, smoke and dust) discharged from exhaust gas. Are harmful gases produced by the engine in the combustion process.
Gas pollutants refer to carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxides (nitrogen oxides). Hydrocarbons are expressed in carbon (C) equivalent, and the hydrocarbon ratio is 1: 1.85. Nitrogen oxides are expressed as nitrogen dioxide (NO2) equivalents.
These harmful gases are produced for different reasons. CO is an intermediate product of incomplete oxidation of fuel, which will be produced when oxygen is insufficient. High concentration and uneven mixture will increase CO in exhaust gas. HC is unburned substance in fuel. Due to uneven mixture and cold combustion chamber wall, some fuel is discharged before combustion.
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