Bayesian estimation of heat transport parameters in fixed beds

1993 ◽  
Vol 36 (8) ◽  
pp. 2209-2221 ◽  
Author(s):  
D.J. Gunn ◽  
M.M.A. Misbah
Author(s):  
Gülşen Doğu ◽  
Timur Doğu

Abstract Moment technique has been extensively used for the evaluation of the rate and equilibrium parameters in chemical reactors and also in adsorption vessels, for about five decades. Adsorption and reaction rate parameters, as well as axial dispersion constants, effective diffusivities within porous catalysts and heat and mass transfer coefficients were shown to be effectively evaluated by analyzing the moments of the response peaks, which could be obtained from pulse-response experiments performed in a reaction/adsorption vessel. A detailed review of chromatographic processes, involving moment analysis of adsorption equilibrium and rate constants in fixed beds, dynamic analysis of batch adsorbers, moment analysis of fluidized bed, slurry and trickle bed reactors are reported in this manuscript. Applications of the single-pellet moment technique, which was developed for the effective investigation of intrapellet rate and equilibrium processes, by eliminating the contributions of axial dispersion and external transport parameters, are comprehensively discussed. Recent studies for the analysis of reaction rate parameters using the TAP reactor approach, use of single pellet system for the investigation of catalytic and non-catalytic solid-gas reactions and extension of the moment technique to non-linear systems opened new pathways in reaction engineering research.


Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2913
Author(s):  
Nico Jurtz ◽  
Urvashi Srivastava ◽  
Alireza Attari Moghaddam ◽  
Matthias Kraume

Process intensification of catalytic fixed-bed reactors is of vital interest and can be conducted on different length scales, ranging from the molecular scale to the pellet scale to the plant scale. Particle-resolved computational fluid dynamics (CFD) is used to characterize different reactor designs regarding optimized heat transport characteristics on the pellet scale. Packings of cylinders, Raschig rings, four-hole cylinders, and spheres were investigated regarding their impact on bed morphology, fluid dynamics, and heat transport, whereby for the latter particle shape, the influence of macroscopic wall structures on the radial heat transport was also studied. Key performance indicators such as the global heat transfer coefficient and the specific pressure drop were evaluated to compare the thermal performance of the different designs. For plant-scale intensification, effective transport parameters that are needed for simplified pseudo-homogeneous two-dimensional plug flow models were determined from the CFD results, and the accuracy of the simplified modeling approach was judged.


Sign in / Sign up

Export Citation Format

Share Document