Diesel Exhaust Particulate Characterization Influence on DPF Regeneration Performance

1
Diesel Exhaust Particulate Characterization-
Influence on DPF Regeneration Performance -
D. Foster, T. Root, T. Kawai, E. Wirojsakunchai,
E. Schroeder, N. Schmidt, C. Kolodziej, R. Yapaulo
Procedure
Objective In addition to filling performance
the regeneration behavior of various DPFs with
different collected soot is examined to better
understand the mechanisms involved. Lab Setup
Kinetic Parameter Estimation
The rate constant as an Arrhenius expression
DPFs are exposed to controlled temperature ramp
and gas-phase emissions are monitored
Good fit with experimental data
The measured emissions are a convolution of the
emissions from the smaller reaction volumes

• Soot oxidation occurs in two distinct events
• Catalytic oxidation at low temps (300 C) ? LT
  Peak
• Thermal (carbon) oxidation (500 600 C) ? HT
  Peak

Temperature Ramp Room T to 700 C (6.67 C/min)
Results
Applying Kinetic Parameters to in-situ
Regeneration
Conclusions
Mode 3, Catalyzed Cordierite, LT HT
Conceptual Model of Regeneration
Stage 1 High filtration efficiency (intact soot
cake) Stage 2 Decreasing filtration efficiency
(transition) Stage 3 Low filtration efficiency
(clean DPF)
Mode 3, Catalyzed Cordierite, LT
Oxy acetylene Burner setup
In situ regeneration results in high thermal
gradients and non-homogeneous soot oxidation rates
Pressure drop and filtration efficiency correlate
well with the amount of HT soot remaining in the
filter
Mode 3, Catalyzed Cordierite, HT