Visualization of Biomass Pyrolysis and Temperature Imaging in a Heated-Grid Reactor
Författare
Summary, in English
The main advantage of a heated-grid reactor for studying pyrolysis kinetics of solid fuel samples is that high heating rates of up to 1000 K/s can be obtained. However, one of the concerns is whether the temperature distribution over the grid material is uniform and whether the presence of a thermocouple welded to the grid causes any measurement errors. Biomass samples were placed on the heated-grid reactor, and the volatiles, emitted in the biomass pyrolysis process as hot gas plumes, were imaged with an infrared camera with a high framing speed. The temporal resolved infrared images indicate that the pyrolysis process does not take place at the same rate everywhere on the grid. Two-dimensional temperature images of a heated grid made of stainless steel were recorded using the method of laser-induced thermometry with thermographic phosphors. As expected from a heat-transfer model, measured temperatures were found to be significantly higher than temperatures indicated by a thermocouple welded to the bottom of the grid. It was also observed that there is a large temperature gradient between the two electrodes on which the grid is connected. It is shown that replacing a wire mesh by a foil as a grid material may lead to more homogeneous temperature distribution. The paper recommends additional research to demonstrate the suitability of the heated-grid reactor for carrying out accurate measurements.
Avdelning/ar
Publiceringsår
2009
Språk
Engelska
Sidor
993-1006
Publikation/Tidskrift/Serie
Energy & Fuels
Volym
23
Issue
1
Dokumenttyp
Artikel i tidskrift
Förlag
The American Chemical Society (ACS)
Ämne
- Atom and Molecular Physics and Optics
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 0887-0624