skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Experimental and theoretical study of diesel soot reactivity

Abstract

In order to provide data for modelling the performance of a regenerative soot filter, a study of the oxidation kinetics of diesel soot in the temperature range from 600 C to 800 C was undertaken. Isothermal burning rates at a number of temperatures were measured in rectangular soot beds within a thermobalance. The technique was easy to use, but the combustion rate was found to depend on bed mass. The oxidation process was thus limited by mass transfer effects. A two-dimensional mathematical model of oxygen transfer was developed to extract the true kinetic rates from experimental data. The two-dimensional approach was required because significant oxygen depletion occurred along both axes. Using assumed kinetic rates, oxygen concentration profiles in the gas phase above the bed and within the bed were calculated. The true kinetics at a number of temperatures were, then established by matching predicted oxygen consumption with measured consumption. Application of the model required values of the effective diffusion coefficient for oxygen within the bed. Accordingly, the structure and properties of the soot aggregates were determined. A supplements study was carried out to identify the appropriate primary reaction products. The measured kinetic rates were then used in a simpler, monodimensionalmore » model to evaluate the mean oxygen mass transfer coefficients to the surface of the bed. The results show that burning below about 730 C is in regime 1 and can be described by K = 6.9 {times} 10{sup 12} exp ({minus}207,000/RT) (s{sup {minus}1}) with R = 8.314 J/mol {times} K. Above, 730 C, there is a decrease in apparent activation energy, probably due to thermal ``annealing,`` which changes the microstructure of the carbon. As a result, the inherent reactivity declines and/or the bed becomes less accessible to oxygen.« less

Authors:
; ; ;  [1]
  1. Univ. de Haute Alsace, Mulhouse (France). Lab. Gestion des Risques et Environnement
Publication Date:
OSTI Identifier:
93210
Report Number(s):
CONF-940711-
TRN: IM9537%%253
Resource Type:
Book
Resource Relation:
Conference: 25. international symposium on combustion, Irvine, CA (United States), 31 Jul - 5 Aug 1994; Other Information: PBD: 1994; Related Information: Is Part Of Twenty-fifth symposium (international) on combustion; PB: 1838 p.
Country of Publication:
United States
Language:
English
Subject:
02 PETROLEUM; DIESEL FUELS; COMBUSTION KINETICS; SOOT; OXIDATION; MATHEMATICAL MODELS; TWO-DIMENSIONAL CALCULATIONS; AGGLOMERATION; MORPHOLOGY; KINETIC EQUATIONS; POLYCYCLIC AROMATIC HYDROCARBONS; AIR POLLUTION CONTROL; PHYSICAL PROPERTIES; CHEMICAL PROPERTIES; EXPERIMENTAL DATA

Citation Formats

Marcuccilli, F, Gilot, P, Stanmore, B, and Prado, G. Experimental and theoretical study of diesel soot reactivity. United States: N. p., 1994. Web.
Marcuccilli, F, Gilot, P, Stanmore, B, & Prado, G. Experimental and theoretical study of diesel soot reactivity. United States.
Marcuccilli, F, Gilot, P, Stanmore, B, and Prado, G. 1994. "Experimental and theoretical study of diesel soot reactivity". United States.
@article{osti_93210,
title = {Experimental and theoretical study of diesel soot reactivity},
author = {Marcuccilli, F and Gilot, P and Stanmore, B and Prado, G},
abstractNote = {In order to provide data for modelling the performance of a regenerative soot filter, a study of the oxidation kinetics of diesel soot in the temperature range from 600 C to 800 C was undertaken. Isothermal burning rates at a number of temperatures were measured in rectangular soot beds within a thermobalance. The technique was easy to use, but the combustion rate was found to depend on bed mass. The oxidation process was thus limited by mass transfer effects. A two-dimensional mathematical model of oxygen transfer was developed to extract the true kinetic rates from experimental data. The two-dimensional approach was required because significant oxygen depletion occurred along both axes. Using assumed kinetic rates, oxygen concentration profiles in the gas phase above the bed and within the bed were calculated. The true kinetics at a number of temperatures were, then established by matching predicted oxygen consumption with measured consumption. Application of the model required values of the effective diffusion coefficient for oxygen within the bed. Accordingly, the structure and properties of the soot aggregates were determined. A supplements study was carried out to identify the appropriate primary reaction products. The measured kinetic rates were then used in a simpler, monodimensional model to evaluate the mean oxygen mass transfer coefficients to the surface of the bed. The results show that burning below about 730 C is in regime 1 and can be described by K = 6.9 {times} 10{sup 12} exp ({minus}207,000/RT) (s{sup {minus}1}) with R = 8.314 J/mol {times} K. Above, 730 C, there is a decrease in apparent activation energy, probably due to thermal ``annealing,`` which changes the microstructure of the carbon. As a result, the inherent reactivity declines and/or the bed becomes less accessible to oxygen.},
doi = {},
url = {https://www.osti.gov/biblio/93210}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Dec 31 00:00:00 EST 1994},
month = {Sat Dec 31 00:00:00 EST 1994}
}

Book:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this book.

Save / Share: