Abstract
In this study, an innovative parallel radial adsorber (here after PRA) has been presented. The motivation behind developing such a configuration was to enhance the performance of adsorption bed by broadening the possible choices of adsorbent diameter. The proposed arrangement effectively reduces the pressure drop by increasing the gas flow contact area; thus, a smaller adsorbent can be applied in the PRA bed. To quantify the performance of the proposed configuration, the governing equations of the system including conservation of energy, mass (diffusion inside the particles and convection outside the particles) and momentum (Ergun equation) were developed and solved numerically. The pressure drop, break-through time, saturation percentage, and duration of regeneration step were chosen as the key factors for evaluating such a configuration. By applying the new configuration, a magnificent diminution of pressure drop resulted. Therefore, small particles which are opted as the adsorbing media will increase the mass transfer area and subsequently mass transfer rate. The capability of handling high flow rate by the proposed configuration offered good potential for reducing the cycle time. Besides showing this potential, owing to the size of the particles in PRA beds, this configuration enhanced the saturation percentage of the column from 88% (axial bed) to 98% for the case study of natural gas dehydration.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Notes
These wire mesh and punched plates have broad usage in sieving and filtering industry.
Abbreviations
- a :
-
Specific surface area (m2/m3)
- b :
-
Adsorption affinity parameter (kpa−1)
- c pg :
-
Gas heat capacity (J/mol K)
- D disp :
-
Axial dispersion coefficient
- D eff :
-
Effective diffusivity in particle (m2/s)
- D m :
-
Molecular diffusivity (m2/s)
- D p :
-
Particle diameter (m)
- E :
-
Affinity constant activation energy (J/mol)
- h :
-
Convective heat transfer coefficient (W/m2 K)
- i :
-
Water or methane
- K :
-
Gas thermal conductivity (W/m K)
- k :
-
Mass transfer coefficient (mol/m2 s)
- L :
-
Bed length (m)
- P :
-
Pressure (Pa)
- Q :
-
Gas volume flow rate (m3/s)
- q p :
-
Adsorbed water per unit volume of pellet (mol/m3)
- q c :
-
Adsorbed water per unit volume of pellet solid structure (mol/m3)
- r :
-
Radial distance
- R :
-
Gas constant (J/mol K)
- R p :
-
Adsorbent particle radius (m)
- t :
-
Time (s)
- T g :
-
Gas tempeature (K)
- T p :
-
Particle temperature (K)
- T in :
-
Inlet gas temperature (K)
- u :
-
Interstitial velocity (m/s)
- u s :
-
Superficial velocity (m/s)
- y :
-
Water vapor mole fraction
- y in :
-
Inlet water vapor mole fraction
- z :
-
Axial distance
- Z :
-
Compressibility factor
- μ :
-
Gas dynamic viscosity (Pa s)
- ε b :
-
Bed porosity
- ε br :
-
Radial bed porosity
- ε ba :
-
Axial bed porosity
- ε p :
-
Pellet porosity
- ρ p :
-
Particle skeleton density (kg/m3)
- ρ g :
-
Gas density (kg/m3)
- ΔH ads :
-
Heat of adsorption (J/mol)
References
Alizadeh-Khiavi, S., Sawada, J., Gibbs, A., Alvaji, J.: Rapid cycle syngas pressure swing adsorption system. In: Google Patents US 20070125228 A1 (2007)
Awad, M.M., Ramzy K, A., Hamed, A.M., Bekheit, M.M.: Theoretical and experimental investigation on the radial flow desiccant dehumidification bed. Appl. Therm. Eng. 28(1), 75–85 (2008) doi:10.1016/j.applthermaleng.2006.12.018
Chen, A.-Q., Wankat, P.C.: Scaling rules and intensification of thermal swing adsorption. AlChE J. 37(5), 785–789 (1991). doi:10.1002/aic.690370516
Chiang, A.S.T., Hong, M.C.: Radial flow rapid pressure swing adsorption. Adsorption 1(2), 153–164 (1995). doi:10.1007/bf00705002
Couper, J.R., Institution of Chemical E: Chemical process equipment: selection and design. Elsevier/Butterworth-Heinemann, Amsterdam; Boston (2012)
Dubé, O., Ackley, M., Celik, C., Chaouki, J., Bertrand, F.: Discrete element simulation of the dynamics of adsorbents in a radial flow reactor used for gas prepurification. Adsorption 20(1), 91–107 (2014). doi:10.1007/s10450-013-9552-1
Gholami, M., Talaie, M.R.: Investigation of simplifying assumptions in mathematical modeling of natural gas dehydration using adsorption process and introduction of a new accurate LDF model. Ind. Eng. Chem. Res. 49(2), 838–846 (2010). doi:10.1021/ie901183q
Gholami, M., Talaie, M.R., Roodpeyma, S.: Mathematical modeling of gas dehydration using adsorption process. Chem. Eng. Sci. 65(22), 5942–5949 (2010). doi:10.1016/j.ces.2010.08.026
Gholami, M., Talaie, M.R., Aghamiri, S.F.: The development of a new LDF mass transfer correlation for adsorption in fixed beds. Adsorption 22(2), 195–203 (2016). doi:10.1007/s10450-015-9730-4
Huang, W.-C., Chou, C.-T.: Comparison of radial- and axial-flow rapid pressure swing adsorption processes. Ind. Eng. Chem. Res. 42(9), 1998–2006 (2003). doi:10.1021/ie020129c
Kareeri, A.A., Zughbi, H.H., Al-Al, H.H.: Simulation of Flow in a Radial Flow Fixed Bed Reactor (rfbr) Paper Presented at the CFD 2005—Fourth International Conference on Computational Fluid Dynamics in the Oil and Gas. Metallurgical & Process Industries, Norway (2005)
Keller, J.S.R.: Gas adsorption equilibria experimental methods and adsorption isotherms. http://public.eblib.com/choice/publicfullrecord.aspx?p=226050 (2005).
Neu, B., Smolarek, J., Emley, M.: Radial adsorption gas separation apparatus and method of use. In. Google Patents, (2003)
Poling, B.E., Prausnitz, J.M., O’Connell, J.P.: The properties of gases and liquids. http://accessengineeringlibrary.com/browse/properties-of-gases-and-liquids-fifth-edition (2001).
Rase, H.F.: Fixed-bed reactor design and diagnostics: gas-phase reactions. http://public.eblib.com/choice/publicfullrecord.aspx?p=1822228 (1990).
Rice, R.G.: Approximate solutions for batch, packed tube and radial flow adsorbers—comparison with experiment. Chem. Eng. Sci. 37(1), 83–91 (1982). doi:10.1016/0009-2509(82)80070-5
Ruthven, D.M.: Principles of adsorption and adsorption processes. Wiley, New York (1984)
Sircar, S.: Applications of gas separation by adsorption for the future. Adsorpt. Sci. Technol. 19(5), 347–366 (2001). doi:10.1260/0263617011494222
Thomas, W.J., Crittenden, B.D.: Adsorption Technology and Design. Butterworth-Heinemann, Boston (1998)
Wen, D., Ding, Y.: Heat transfer of gas flow through a packed bed. Chem. Eng. Sci. 61(11), 3532–3542 (2006) doi:10.1016/j.ces.2005.12.027
Yang, R.T.: Gas Separation by Adsorption Processes. Imperial College Press, London (1999)
Yang, R.T.: Adsorbents: Fundamentals and Applications. Wiley, New York (2003)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Salimi, S., Gholami, M. Theoretical study of parallel radial adsorber: a novel configuration of temperature swing gas adsorption bed. Adsorption 23, 871–878 (2017). https://doi.org/10.1007/s10450-017-9899-9
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10450-017-9899-9