tSaoir, Meabh Nic An and Abreu Fernandes, Daniel Luis and Sa, Jacinto and McMaster, Michael and Kitagawa, Kuniyuki and Hardacre, Christopher and Aiouache, Farid (2011) Visualization of water vapour flow in a packed bed adsorber by near-infrared diffused transmittance tomography. Chemical Engineering Science, 66 (24). pp. 6407-6423. ISSN 0009-2509
Full text not available from this repository.Abstract
This work presents a procedure based on spatially-resolved near-infrared imaging, in order to observe temperature and composition maps in gas-solid packed beds subjected to effects of aspect ratio and non-isothermal conditions. The technique was applied to the water vapour flow in a packed bed adsorber of low aspect ratio, filled with silica gel, using a tuneable diode laser, focal planar array detector and tomographic reconstruction. The 2D projected images from parallel scanning permitted data to be retrieved from the packing and above the packing sections of 12.0 x 12.0 x 18.2 mm(3) at a volume-resolution of 0.15 x 0.15 x 0.026 mm(3) and a time-resolution of less than 3 min. The technique revealed uneven temperature and composition maps in the core packed bed and in the vicinity of the wall due to flow maldistribution. In addition, the heat uptake from the packed bed and local cross-mixing were experimentally ascertained by local profiles of the water vapour composition and temperature under various aspect ratios and feed flow rates. The relative deviations in temperature and compositions were 11.1% and 9.3%, respectively. The deviation in composition, which covers the packing and above the packing sections, was slightly higher than the deviation of 8% obtained up-to-date but was limited to the exit of a packed bed adsorber.