What aspects should be noted when adding and using vehicle urea solution?

Automotive urea aqueous solution is a transparent liquid. For the addition and use of automotive urea water, what aspects should we pay attention to? Urea aqueous solution is also known as diesel exhaust fluid, commonly referred to in China as: automotive urea, vehicle urea, automotive environmental urea, vehicle denitration agent, with the most common term being automotive urea.

There is a separate container on the truck to store the urea solution. During use, neither water nor diesel should be added to the urea solution. Once the engine starts operating, the ECU precisely measures the injection amount of the urea solution based on the diesel engine's operating conditions, catalyst temperature, and environmental status. The urea solution is injected into the exhaust pipe, where it mixes uniformly with the diesel engine's exhaust gases and undergoes a chemical reaction.

Currently, the mainstream route for upgrading heavy-duty diesel engines to China V in China is the SCR route, which employs selective catalytic reduction technology. The operational process roughly involves exhaust gases exiting the turbine and entering the exhaust pipe, where a urea dosing injection device is installed to spray a urea aqueous solution. The urea solution and nitrogen oxides in the exhaust undergo redox reactions in the SCR reaction tank, producing nitrogen and water that are then discharged. The urea dosage in the SCR system is controlled by the engine management system, with the amount of urea injected needing to match the concentration of NOx.

The cost of using diesel exhaust fluid (DEF) is also a concern for us. When it comes to usage costs, it mainly consists of two aspects: the purchase cost of the vehicle itself for National IV and V models, and the cost of using DEF. At first glance, adopting National IV and V products seems to impose significant costs on truck drivers, but is this really the case? In fact, for users, the purchase cost of National IV and V vehicles increases by 20,000 to 30,000 yuan, and DEF consumption is 4% to 6% of fuel consumption, which also leads to additional costs for National IV vehicles. However, fuel savings compared to the original National III engines amount to 3% to 5%. These fuel cost savings can offset these expenses.

When it comes to the use of diesel exhaust fluid (DEF), attention must be paid to the refilling method. The future direction of DEF refilling involves installing DEF dispensers at gas stations, ensuring the purity of the fluid and protecting it from contamination during the refilling process. Another refilling option is using packaged barrels, where the fluid can be easily and conveniently poured through the included funnel tube.