Effects of Diesel Fuel Sulfur Level on Performance of a Continuously Regenerating Diesel Particulate Filter and a Catalyzed Particulate Filter

This paper reports the test results from the DPF (diesel particulate filter) portion of the DECSE (Diesel Emission Control - Sulfur Effects) Phase 1 test program. The DECSE program is a joint government and industry program to study the impact of diesel fuel sulfur level on aftertreatment devices.

A systematic investigation was conducted to study the effects of diesel fuel sulfur level on (1) the emissions performance and (2) the regeneration behavior of a continuously regenerating diesel particulate filter and a catalyzed diesel particulate filter. The tests were conducted on a Caterpillar 3126 engine with nominal fuel sulfur levels of 3 parts per million (ppm), 30 ppm, 150 ppm and 350 ppm. It is concluded from this study that (1) both DPF devices are effective in removing the soot and soluble organic fraction (SOF) portion of the particulate matter (PM), but they also convert 40 to 60% of the fuel sulfur into sulfate PM over the OICA cycle, (2) fuel sulfur level has only moderate influence on hydrocarbon (HC), carbon monoxide (CO) and nitrogen oxide (NO_x) emissions, and (3) reducing fuel sulfur reduces the regeneration temperature of both DPF devices at low fuel sulfur level.