Diesel quality impact of emissions from vehicles
Source：China's environmental Author： Date：6,10,2012
The diesel is a petroleum processing has been refined. It is a mixture of various hydrocarbons, mainly composed of carbon and hydrogen, containing a small amount of impurities such as oxygen, nitrogen and sulfur. Vehicle diesel fuel, light diesel oil, light diesel performance indicators include: the angry, evaporation, viscosity, low temperature fluidity, corrosive, and ash, water, machinery and other impurities. Among them, the greater impact on the indicators of vehicle emissions is pyrophoric (referring to the cetane number), corrosive (mainly referring to the sulfur content) and chemical composition.
The ignition of the fuel self-ignition capacity. Self-ignition temperature combustion without ignition when the fuel reaches a certain temperature called the ignition point, spontaneous combustion of the diesel cetane number or cetane index. Cetane number of diesel engine emissions performance. Cetane number less than that the ignitability of the ignition delay was longer, too many pre-mixed combustion, resulting in brutal operation, the noise increase, NOx emissions increase. The cetane number is too high, lower the thermal stability of diesel, the formation of a large number of difficult to complete combustion of free carbon in the high temperature and pressure inside the cylinder to extend the lead after burning, smoky increase, reduce engine power, increased fuel consumption. Diesel engine emissions of various pollutants, generally decreases with the increase of fuel cetane. Conventional diesel fuel cetane number between 40 to 50, low emission diesel cetane number of 55 or more.
Cars with diesel corrosive sulfur content, acidity, copper corrosion grade indicators said. On emissions the greatest impact is the sulfur content. Diesel sulfur by combustion generates sulfur dioxide and particulate sulfide, sulfur is about 98% of the SO2 discharge. The rest of the formation of sulfuric acid and various metal sulfides granular discharge is an important part of diesel engine particulate matter emissions. Therefore, reduce the sulfur content in diesel to a corresponding reduction in emissions of particulates and sulfur will also make diesel vehicles, catalytic converter failure.
Of light diesel oil production of straight-run refining, accounting for more than 50% of the production-diesel. Straight-run diesel fuel cetane number, the coke quality, aromatics, sulfur content and so is relatively low. Secondary processing cracking diesel components should be as the car diesel hydrotreating, but the majority of China's secondary cracking diesel without hydrotreating reconcile into diesel, resulting in poor diesel fuel quality in China.
The ignition of the fuel self-ignition capacity. Self-ignition temperature combustion without ignition when the fuel reaches a certain temperature called the ignition point, spontaneous combustion of the diesel cetane number or cetane index. Cetane number of diesel engine emissions performance. Cetane number less than that the ignitability of the ignition delay was longer, too many pre-mixed combustion, resulting in brutal operation, the noise increase, NOx emissions increase. The cetane number is too high, lower the thermal stability of diesel, the formation of a large number of difficult to complete combustion of free carbon in the high temperature and pressure inside the cylinder to extend the lead after burning, smoky increase, reduce engine power, increased fuel consumption. Diesel engine emissions of various pollutants, generally decreases with the increase of fuel cetane. Conventional diesel fuel cetane number between 40 to 50, low emission diesel cetane number of 55 or more.
Cars with diesel corrosive sulfur content, acidity, copper corrosion grade indicators said. On emissions the greatest impact is the sulfur content. Diesel sulfur by combustion generates sulfur dioxide and particulate sulfide, sulfur is about 98% of the SO2 discharge. The rest of the formation of sulfuric acid and various metal sulfides granular discharge is an important part of diesel engine particulate matter emissions. Therefore, reduce the sulfur content in diesel to a corresponding reduction in emissions of particulates and sulfur will also make diesel vehicles, catalytic converter failure.
Of light diesel oil production of straight-run refining, accounting for more than 50% of the production-diesel. Straight-run diesel fuel cetane number, the coke quality, aromatics, sulfur content and so is relatively low. Secondary processing cracking diesel components should be as the car diesel hydrotreating, but the majority of China's secondary cracking diesel without hydrotreating reconcile into diesel, resulting in poor diesel fuel quality in China.