Characteristics of DPF for Diesel Engine Fueled with Biodiesel Fuel - Second Report: Exhaust Gas Emission Characteristics at Self-Regeneration of DPF

In our first study[1], we reported that the self-regeneration of DPF is enabled by the function of residual potassium methoxide (CH₃OK) as catalyst, contained in biodiesel fuel that is collected in the DPF at lower engine loads[1]. In the present report, exhaust emission characteristics after using DPF were investigated by continuous measurement of exhaust gas. The results show that the self-regeneration of DPF occurs when engine loads change from lower to higher, and at the same time, methanol concentration in exhaust gas reaches to a higher peak. This peak is higher than when self-regeneration does not take place. The higher concentration of methanol is reduced by repeating the self-regeneration. The SOF content in PM is reduced by DPF at both high and low engine load, which is a characteristic that was not seen with gas oil.