Why Do Vehicles Need Urea?
2 Answers
Vehicles require urea for the following reasons: 1. To reduce vehicle exhaust emissions; 2. To convert harmful nitrogen oxides in the exhaust into nitrogen and water. Diesel vehicles equipped with a urea system need a urea tank to store the urea solution. The ECU calculates the theoretical generation of nitrogen oxides based on data such as engine speed and fuel injection volume. Vehicle urea plays a crucial role in the vehicle's power and fuel consumption. Failure to use diesel exhaust fluid or using urea solutions with insufficient purity or inferior quality can cause the vehicle's engine to automatically reduce speed. Inferior-quality diesel exhaust fluid can contaminate the catalyst in the SCR catalytic reaction tank, leading to damage to the components of the after-treatment system.
Diesel vehicles use urea to treat exhaust gases, making emissions more environmentally friendly. As someone who cares about sustainability, I find this technology pretty cool. Simply put, diesel engines produce nitrogen oxides, abbreviated as NOx, which are highly polluting to the air, contributing to issues like smog. By adding a urea solution called AdBlue, which is injected into the exhaust pipe via the SCR system, NOx reacts with the urea in the presence of a catalyst to form harmless nitrogen and water vapor. This helps meet emission standards, such as China's National VI regulations. Without it, vehicles risk fines for exceeding emission limits and may face speed restrictions or trigger warning lights. Having driven diesel pickups a few times, I know the urea tank needs refilling every few thousand kilometers. The cost is low—just a few yuan per liter—and it’s more fuel-efficient and easier to maintain than gasoline vehicles. From an environmental perspective, this small step helps keep the air cleaner, protecting both the environment and public health.
