es7b05633_si_001.pdf (2.51 MB)
Emissions During and Real-world Frequency of Heavy-duty Diesel Particulate Filter Regeneration
journal contribution
posted on 2018-04-19, 00:00 authored by Chris Ruehl, Jeremy D. Smith, Yilin Ma, Jennifer Erin Shields, Mark Burnitzki, Wayne Sobieralski, Robert Ianni, Donald J. Chernich, M.-C. Oliver Chang, John Francis Collins, Seungju Yoon, David Quiros, Shaohua Hu, Harry DwyerRecent
tightening of particulate matter (PM) emission standards
for heavy-duty engines has spurred the widespread adoption of diesel
particulate filters (DPFs), which need to be regenerated periodically
to remove trapped PM. The total impact of DPFs therefore depends not
only on their filtering efficiency during normal operation, but also
on the emissions during and the frequency of regeneration events.
We performed active (parked and driving) and passive regenerations
on two heavy-duty diesel vehicles (HDDVs), and report the chemical
composition of emissions during these events, as well as the efficiency
with which trapped PM is converted to gas-phase products. We also
collected activity data from 85 HDDVs to determine how often regeneration
occurs during real-world operation. PM emitted during regeneration
ranged from 0.2 to 16.3 g, and the average time and distance between
real-world active regenerations was 28.0 h and 599 miles. These results
indicate that regeneration of real-world DPFs does not substantially
offset the reduction of PM by DPFs during normal operation. The broad
ranges of regeneration frequency per truck (3–100 h and 23–4078
miles) underscore the challenges in designing engines and associated
aftertreatments that reduce emissions for all real-world duty cycles.