The working principle of DPF

DPF， The core working principle of the diesel particulate filter is to use a wall flow honeycomb ceramic structure to capture, store, and oxidize particulate matter in exhaust gas. When the exhaust gas passes through the DPF, particulate matter will be captured and attached to the wall flow honeycomb ceramic. As the accumulated particulate matter increases, the DPF will gradually clog. In order to restore its filtering effect, regular regeneration treatment is required to oxidize the captured particulate matter into harmless substances through high-temperature combustion or the action of catalysts, thereby restoring the filtering performance of DPF.

The wall flow particulate trap, as the mainstream technology of DPF, adopts a closed wall flow structure as the carrier, which can efficiently intercept and capture particulate matter in exhaust gas. The regeneration process includes two methods: active regeneration and passive regeneration. Active regeneration uses DOC (oxidation catalyst) to oxidize diesel fuel injected into the cylinder or exhaust pipe, thereby increasing the exhaust temperature and allowing the captured particulate matter to burn, thereby restoring the filtration performance of the carrier. Passive regeneration utilizes DOC to convert NO into NO2, which then continuously oxidizes the particles intercepted by the carrier to prevent carrier blockage.