Urea, also known as urea, is a white crystal. One of the simplest organic compounds. Diamide of carbonic acid, the molecular formula is H2NCONH2(CO(NH2)2). The main nitrogen-containing end products of protein metabolism in mammals and some fishes.
Urea for vehicles has many names. Automotive urea solution was first used in Europe, called Adblue, in North America called DEF(DieselExhaustFluid), and in China called automotive urea solution or "automotive denitration agent". But now it is generally called "urea for vehicles" in China.
The vehicle urea solution is a colorless and transparent clear liquid with a concentration of 3 1.8%-33.2%, which is used to reduce nitrogen oxides. At present, the vehicle urea solution is generally composed of 32.5% high-purity urea and 67.5% deionized water.
Taking China's first batch of automotive urea plus blue, which was certified by ADBlue of German Automobile Industry Association (VDA), as an example, we know something about automotive urea. Blue is a registered trademark of nitrogen oxide reducing agent (AUS32) for diesel engines. It is a solution containing 32.5% urea, which is used in selective catalytic reduction system (SCR) to reduce nitrogen oxide emissions from diesel vehicles. AUS32 is a urea solution made of 32.5% high-purity urea and purified water, with clear appearance, no toxin and safe use. This is a non-explosive, non-flammable and environmentally friendly solution. AUS32 belongs to the lowest risk category among transportable liquids, and it is neither fuel nor fuel additive. However, heavy vehicles need it to carry out denitrification operation in specially configured storage tanks. Refueling AUS32 is as simple as refueling. Even if you spill AUS32 on your hands, just rinse it with clear water.
Generally speaking, the average consumption of AUS32 is 3-5% of the diesel consumption. For every 100 liter of diesel consumed by automobiles, only about 3-5 liters of AUS32 is used, so the consumption of AUS32 required by customers is much less than that of diesel. If the storage method is correct, AUS32 has a one-year shelf life. The storage location of AUS32 must be far away from direct sunlight, the temperature should not be too hot or too cold, and it should be in a well-ventilated storage area. The freezing point of this solution is-1 1 celsius, and it will maintain its original quality after dissolution. When not in use, it should be stored in a sealed package.
Automobile selective catalytic reduction exhaust aftertreatment (SCR) is a technology that ammonia produced by urea reaction reacts with automobile exhaust, and it is a comprehensive emission control system certified to meet national IV regulations. This is a technology to control nitrogen oxides in diesel engine exhaust.