Three Main Reasons For Crystallization Plugging In AdBlue® Machine

Three Main Reasons for Crystallization Plugging in AdBlue® Machine

2019-09-09 11:49:08

There are three reasons for the blockage of urea crystallization in AdBlue® production machine. Here are three main reasons for the blockage ;

I. Atomization effect or failure of the nozzle

SCR system can be divided into two types: air-free type and air-assisted type. Generally, the working pressure of air-assisted urea injection is relatively high, so it may occur that the nozzle valve needle is not closed tightly, resulting in the low exhaust temperature stage of the work still working, AdBlue® can not be hydrolyzed at high temperature so as to crystallize rapidly. The air-assisted AdBlue® nozzle is usually open, and its atomization is assisted by air pressure, such as the malfunction of the pressure pipeline of AdBlue® pump or the explosion and cracking of the nozzle at high temperature. It will cause poor spray atomization, resulting in crystallization blockage.

2. Imperfect clearance of AdBlue® pump after vehicle extinguishing

Since there is residual liquid in the AdBlue® pump and pipeline after the vehicle stops working, it is necessary to perform clearing work to prevent crystallization or freezing after the ignition switch is turned off. This function will start up and empty the remaining liquid in the pipeline after engine shutdown. But don't turn off the key power switch for a while. In the actual use process, drivers mostly neglect this point of attention. Over time, the crystallization of AdBlue® will be blocked due to the incomplete emptying of the pipeline of the AdBlue® production equipment.

3. The filter element of AdBlue® pump has not been replaced regularly.

All AdBlue® pumps have filters or filter elements. Technical requirements must be regularly cleaned or replaced. Otherwise, a long time will lead to blockage or damage and loss of filter function, which will inevitably lead to system work disorder. If the dust is carelessly brought into the tank when if the filter function fails and AdBlue® is added, it will easily cause blockage of the nozzle if the filter function fails. The nozzle of the post-treatment system has four holes. And it will inevitably lead to poor atomization and crystallization if one or two holes are blocked.

4. Performance failure or damage of other external sensor and actuator components

For example: when the performance failure of the exhaust temperature sensor occurs, the actual exhaust temperature may be 100 degrees Celsius. The system will inject AdBlue® in advance if the sensor feeds back to the computer at 200 degrees Celsius and the AdBlue® injection can not be hydrolyzed and gasified in the exhaust gas at low temperature. Naturally, crystallization will occur at the carrier of the catalyst, and over time, a hard AdBlue® crystallization will be formed.

5. Catalyst Failure Caused by Vehicle Use of Low-quality Diesel Oil and Work Environment

The catalyst of SCR system is to promote chemical anti-abandonment of ammonia decomposed from AdBlue® of production equipment by hydrolysis and gasification at high temperature and NOx in waste. It has high technical requirements for sulfur content in diesel oil. The sulfide formed at high temperature has irreversible destructive effect on the catalyst. Once the catalyst fails, it will cause excessive exhaust gas and limit engine power output.

EverBlue Chemicals always provide the best adblue® high quality and we also provides maintenance and repaire of vehicle SCR system in China to provide the best service to customers.