High-pressure catalytic combustion of gasified biomass in a hybrid combustor
2005 (English)In: Applied Catalysis A: General, ISSN 0926-860X, E-ISSN 1873-3875, Vol. 293, no 1-2, 129-136 p.Article in journal (Refereed) Published
Catalytic combustion of synthetic gasified biomass was conducted in a high-pressure facility at pressures ranging from 5 to 16 bars. The catalytic combustor design considered was a hybrid monolith (400 cpsi, diameter 3.5 cm, length 3.6 cm and every other channel coated). The active phase consisted of 1 wt.% Pt/gamma-Al2O3 With wash coat loading of total monolith 15 wt.%. In the interpretation of the experiments, a twodimensional boundary layer model was applied successfully to model a single channel of the monolith. At constant inlet velocity to the monolith the combustion efficiency decreased with increasing pressure. A multi-step surface mechanism predicted that the flux of carbon dioxide and water from the surface increased with pressure. However, as the pressure (i.e. the Reynolds number) was increased, unreacted gas near the center of the channel penetrated significantly longer into the channel compared to lower pressures. For the conditions studied (lambda = 46, T-in = 218-257 degrees C and residence time similar to 5 ms), conversion of hydrogen and carbon monoxide were diffusion limited after ignition, while methane never ignited and was kinetically controlled. According to the kinetic model surface coverage of major species changed from CO, H and CO2 before ignition to O, OH, CO2 and free surface sites after ignition. The model predicted further that for constant mass flow combustion efficiency increased with pressure, and was more pronounced at lower pressures (2.5-10 bar) than at higher pressures (> 10 bar).
Place, publisher, year, edition, pages
2005. Vol. 293, no 1-2, 129-136 p.
catalytic combustion, gasified biomass, platinum, high pressure, catalytically stabilized combustion, CHEMKIN
IdentifiersURN: urn:nbn:se:kth:diva-7571DOI: 10.1016/j.apcata.2005.07.003ISI: 000232436200014ScopusID: 2-s2.0-24644491216OAI: oai:DiVA.org:kth-7571DiVA: diva2:12638
QC 201009162007-11-062007-11-062014-04-09Bibliographically approved