Why is urea added to large buses?
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Dear experts: I’ve recently noticed that large buses (such as youth buses) are filled with fuel oil and urea. What is the purpose and mechanism of adding urea? Thank you!
I was also puzzled the first time I saw it; the driver said it is used in combination with fuel to meet higher emission standards. Jinlong Bus. The following information comes from Baidu searches: 1. Jinlong Bus……Urea is used to meet stricter emissions standards; among domestic manufacturers, it is employed as a way to cut costs……Drivers say that on the 9-meter G3 model, the air conditioning temperature doesn’t rise above 40 degrees Celsius even when it’s turned on in summer, while the V6LE model manages to reach around 80 degrees…… 2. Environmental protection vehicle urea (English: Diesel exhaust fluid; its official scientific name is AUS32; in the US and Canada it’s called DEF, while in Europe it’s known as AdBlue. It’s commonly referred to as vehicle urea. In China, it was named nitrogen oxide reducer in 2012) refers to the same product, which is a substance used to reduce emissions in diesel vehicles. AdBlue is composed of 32.5% urea and 67.5% deionized pure water. The SCR system includes automotive urea and a selective catalytic reducer. The automotive urea is introduced into the burned exhaust gases, where it is converted into ammonia (Ammonia, NH3) by the hot exhaust gases. Ammonia then undergoes a chemical reduction reaction with the nitrogen oxides (NOx) present in the catalytic converter, resulting in the formation of nitrogen and water, substances that do not pose a threat to the natural environment. The typical ratio between diesel and automotive urea is 20:1; in other words, for every 20 parts of diesel used, 1 part of urea is required. -----Source: Wikipedia
Urea is used for denitration, in systems such as catalytic denitration SCR and non-catalytic SNCR, to remove nitrogen oxides from vehicle exhaust. Is enforcement starting now?
The original poster is very thoughtful; it’s a fascinating topic to study
I’ve learned it: for small things, ask Baidu; for big things, ask my wife!
I heard about it for the first time – it’s really informative!
I’m hearing about it for the first time too, thanks to the original poster :)
I heard about it for the first time; I hadn’t paid attention before~~
Environmental regulations have become stricter. The main pollutant in engine exhaust is nitrogen oxides, namely *ao acid radicals. In the commonly used denitration method of non-catalytic reduction, SNCR, urea or ammonia water can be used. Ammonia water is volatile and has a strong odor, so urea is usually used instead. A few months ago, there was a program on China Central Television that talked about how some car dealers pretended that older models met the new national standards.
Not bad, learning knowledge indeed; I noticed it for the first time
True, small issues can lead to big problems. Learned* it