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Visualization of Biomass Pyrolysis and Temperature Imaging in a Heated-Grid Reactor

Prins, A. J.; Lindén, Johannes LU ; Li, Zhongshan LU ; Bastiaans, R. J. M.; van Oijen, J. A.; Aldén, Marcus LU and de Goey, L. P. H. (2009) In Energy & Fuels 23(1). p.993-1006
Abstract
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... (More)
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. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Energy & Fuels
volume
23
issue
1
pages
993 - 1006
publisher
The American Chemical Society
external identifiers
  • wos:000263629900147
  • scopus:64249131033
ISSN
0887-0624
DOI
10.1021/ef800419w
language
English
LU publication?
yes
id
acf6c680-f699-4380-aa8e-b28c8db9e164 (old id 1371919)
date added to LUP
2009-05-08 17:29:57
date last changed
2017-09-10 04:22:08
@article{acf6c680-f699-4380-aa8e-b28c8db9e164,
  abstract     = {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.},
  author       = {Prins, A. J. and Lindén, Johannes and Li, Zhongshan and Bastiaans, R. J. M. and van Oijen, J. A. and Aldén, Marcus and de Goey, L. P. H.},
  issn         = {0887-0624},
  language     = {eng},
  number       = {1},
  pages        = {993--1006},
  publisher    = {The American Chemical Society},
  series       = {Energy & Fuels},
  title        = {Visualization of Biomass Pyrolysis and Temperature Imaging in a Heated-Grid Reactor},
  url          = {http://dx.doi.org/10.1021/ef800419w},
  volume       = {23},
  year         = {2009},
}