Co-current combustion of oil shale – Part 2: Structure of the combustion front

• Published in: Fuel (Guildford) Vol. 89; no. 1; pp. 133 - 143
• Main Authors: Martins, M.F., Salvador, S., Thovert, J.-F., Debenest, G.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 2010; Elsevier
• Subjects: Applied sciences; Combustion front; Combustion of solid fuels; Combustion. Flame; Energy; Energy. Thermal use of fuels; Engineering Sciences; Exact sciences and technology; Front structure; Oil shale; Reactive fluid environment; Reactive porous medium; Smoldering; Theoretical studies. Data and constants. Metering; Front structure; Reactive porous medium; Oil shale; Combustion front; Smoldering; Heat of combustion; Pyrolysis; Pore structure; Shale oil; Porous medium; Combustion; Char; Oxidation; huile schiste; front combustion
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2009.06.040

Timahdit oil shale was used as a porous medium to characterize the structure of a combustion front propagating with co-current downward air supply. A new 1D experimental device was first calibrated using a model porous medium. With the model porous medium, the front propagates as a plane and horizontal surface while using oil shale the front propagates as an inclined curved surface. The peak temperature was 1100 °C; despite the relatively large diameter of the cell (91 mm) and the good thermal insulation, the heat losses were estimated at 42% of the heat released by the combustion. The thickness of the front was characterized using a new gas micro-sampling system: the char oxidation and the carbonate decarbonation zones are approximately 10 and 15 mm thick, respectively. The oil formed during the pyrolysis is adsorbed in the porous medium in the course of the experiment, and expulsed from the cell by the end.