Through advanced filtration technology and high - quality materials, we ensure that our DPFs meet the most stringent environmental standards helping to improve air quality and protect the environment.
Through advanced filtration technology and high - quality materials, we ensure that our DPFs meet the most stringent environmental standards helping to improve air quality and protect the environment.
Challenges and Solutions of DPF Regeneration Technology
The regeneration process of DPF is divided into two methods: passive regeneration and active regeneration. Active regeneration is a process in which, during actual operation, when the exhaust temperature cannot reach the conditions for passive regeneration, fuel injection is used to trigger an oxidation reaction in the DOC, thereby raising the exhaust temperature to above 550 ° C and promoting the combustion oxidation reaction of carbon particles to generate carbon dioxide. Active regeneration is further divided into driving regeneration and in-situ regeneration. The former is automatically triggered when the engine is running under load, such as on highways and provincial roads; The latter requires the driver to stop and press the regeneration button after running at low speed and low load for a period of time, usually after the regeneration indicator light is on.
Passive regeneration is achieved by oxidizing NO to NO2 in DOC, utilizing the activity of NO2 to oxidize carbon particles within the temperature range of 250-450 ° C. However, passive regeneration may also face some problems, such as sulfur in fuel forming sulfate particles at high temperatures, leading to increased particle emissions; Sulfate adheres to the carrier coating, damaging the coating and producing toxic and harmful substances, hindering gaseous catalytic reactions, rendering regeneration ineffective, and ultimately affecting engine performance. In addition, insufficient combustion of ash and burning of engine oil may also cause complete blockage of DPF, increase exhaust back pressure, and further affect engine performance. When the air passage of the DPF carrier is blocked by the emitted soot particles, the PM cannot be completely regenerated and burned, and regular manual cleaning of the DPF is required. The cleaning methods usually include high-temperature heating, ultrasound+cleaning agent, and water+cleaning agent circulation. The high-temperature heating cleaning method is widely adopted abroad due to its short time, energy saving and environmental protection, and good effect. However, ultrasound and water washing methods may have an impact on the precious metal coating inside the DPF pores, and wastewater treatment is difficult and the cost of cleaning agents is high. Therefore, it is not recommended to use water washing methods temporarily.
