Study of the Influence of DPF Regeneration Conditions on the Oxidation Characteristics of Particulate Matter in Biodiesel Combustion

Abstract

After a diesel engine is fueled with biodiesel, the morphology and oxidation activity of particulate matter will change, which will affect the performance and regeneration effect of the diesel particle filter (DPF). This article measured the CO2 concentration and regeneration efficiency during the DPF regeneration process under different biodiesel blending ratios, carbon load, heating rates, gas flow rates, and ash content by building a regeneration burner test bench and explored the influence of different regeneration conditions on the oxidation characteristics of biodiesel particulate matter. The results showed that with the increase of biodiesel blending ratio, carbon load, heating rate, and ash content, the CO2 concentration increased and the regeneration efficiency was improved. Notably, when using pure biodiesel, the regeneration efficiency can reach up to 94%. Thermogravimetric analysis showed that under different regeneration conditions, the particle oxidation activity did not change significantly when the regeneration temperature was between 300°C and 400°C, but the activity changed significantly at 500°C. Increasing carbon loading, heating rate, gas flow rate, and ash content to some extent helped improve oxidation activity. Scanning electron microscopy analysis revealed that an increase in biodiesel blending ratio leads to a decrease in particle size and an increase in quantity, and the particles become finer during oxidation, with an increase in porosity and internal voids. The practical application value of this study lies in revealing the influence of DPF regeneration conditions on the oxidation characteristics of particulate matter in biodiesel combustion. Research has found that with increasing biodiesel blending ratio, carbon load, heating rate, and ash content, the oxidation activity of particulate matter and DPF regeneration efficiency are significantly improved. This means that diesel engines using biodiesel can filter and regenerate particulate matter more efficiently, and the improvement of DPF regeneration efficiency can reduce DPF clogging speed and regeneration frequency, thereby reducing the pressure on the engine system and improving its overall reliability and durability. In addition, morphological changes such as reduced particle size and increased porosity help to more effectively capture and oxidize particulate matter, thereby improving the overall performance and environmental benefits of diesel engines. These findings provide a scientific basis for optimizing the application of biodiesel in diesel engines and help promote the development of cleaner and more efficient diesel engine technologies.