Effects of Particle Stratification on Fixed Bed Absorber Performance
Publication: Journal of Environmental Engineering
Volume 125, Issue 8
Abstract
The effects of adsorbent particle size distribution (PSD) and the layering of particles in stratified and reverse stratified modes on the performance of fixed bed adsorber were investigated. Using trichloroethylene as the adsorbate and granular activated carbon as the adsorbent, experimental studies were conducted in stratified beds for different flow rates and influent concentrations. The homogeneous solid diffusion model was modified to take into account PSD and was used to simulate breakthrough curves. The PSD-based model was validated using experimental data and was found to be more accurate in predicting the breakthrough curves than the non-PSD-based model. The validated model was used to conduct simulations to examine the effects of key variables on performance in the stratified and reverse stratified modes. In the reverse stratified mode, the adsorbent particle size decreases gradually in the direction of flow. Model simulations indicate that this mode of operation increases breakthrough time, decreases the time to reach saturation, and thereby increases the overall adsorbent capacity utilization. The mass transfer zone for the reverse stratified bed was found to be narrower and sharper than that for the stratified bed. These model predictions have important ramifications to the water and wastewater industry in terms of reducing the overall cost of treatment using granular activated carbon adsorption.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Adams, J. Q., and Clark, R. M. (1989). “Cost estimates for GAC treatment systems.” J. AWWA, 81(1), 35–42.
2.
Basmadjian, D. (1983). “The adsorption drying of gases and liquids.” Advances in drying, A. S. Mujundar, ed., Hemisphere, Washington, D.C.
3.
Crittenden, J. C., and Weber, W. J., Jr. (1978). “Predictive model and design of fixed bed adsorbers: Parameter estimation and model development.”J. Envir. Engrg., ASCE, 104(2), 185–197.
4.
Dwivedi, P. N., and Upadhyay, S. N. (1977). “Particle fluid mass transfer in fixed and fluidized bed.” Ind. Engrg. Chem. Proc. Des. and Devel., 16, 157–165.
5.
Fox, C. R., and Kennedy, D. C. (1985). Conceptual design of adsorption systems. Marcel Dekker, New York.
6.
Hindmarsh, A. C. (1980). “LSODE and LSOD1 two new initial value ordinary differential equation solvers.” ACM-SIGNUM Newsletter, 15, 10–11.
7.
Lee, S. ( 1991). “Comparison of deterministic and stochastic analyses of adsorption in batch and fixed bed adsorbers,” PhD thesis, Kansas State University, Manhattan, Kans.
8.
Lee, S. M., Mathews, A. P., and Nassar, R. (1991). “Stochastic modeling of multicomponent adsorption kinetics with nonlinear isotherm.” Proc., IAWQ Specialized Conf. on Appropriate Waste Mgmt. Tech. in Developing Countries.
9.
Mathews, A. P. ( 1975). “Mathematical modeling of multicomponent adsorption in batch reactors,” PhD thesis, University of Michigan, Ann Arbor, Mich.
10.
Mathews, A. P. (1983). “Adsorption in agitated slurry of polydisperse particles.” AIChE Symp. Ser., 230, 79, 18–25.
11.
Mathews, A. P. ( 1984). “Dynamics of adsorption in a fixed bed of polydisperse particles.” Fundamentals of adsorption, A. L. Myers and G. Belfort, eds., Engineering Foundation, New York, 60–66.
12.
Mathews, A. P., and Zayas, I. (1989). “Particle size and shape effects on adsorption rate parameters.”J. Envir. Engrg., ASCE, 115(1), 41–50.
13.
Pirbazari, M., Ravindran, V., Badriyha, B. N., Craig, S., and McGuire, M. J. (1993). “GAC adsorber design protocol for removal of off-flavors.” Water Res., 27, 1153–1166.
14.
Pota, A. A., and Mathews, A. P. (1999). “Adsorption dynamics in a stratified convergent tapered bed.” Chemical Engrg. Sci., in press.
15.
Redlich, O., and Peterson, C. (1959). “A useful adsorption isotherm.” J. Physical Chemistry, 63, 1024.
16.
Shpirt, E. A., and Alben, K. T. (1986). “Changes in particle size distribution on a fixed bed of granular activated carbon.” Water Sci. and Technol., 18(1), 31–42.
17.
Snoeyink, V. ( 1990). “Adsorption of organic compounds.” Water quality and treatment, AWWA, 4th Ed., McGraw-Hill, New York.
18.
Thacker, W. E., Snoeyink, V., and Crittenden, J. C. (1981). “Modeling of activated carbon and coal gasification char adsorbents in single solute and bisolute.” Res. Rep. No. 161, Water Res. Ctr., University of Illinois, Urbana, Ill.
19.
Traegner, U. K., Suidan, M. T., and Kim, B. R. (1991). “Considering age and particle size distribution of activated carbon particles in a completely mixed adsorber at steady state.” Water Res., 30(6), 1495–1501.
20.
Veeraraghavan, S., Mathews, A. P., and Fan, L. T. (1991). “Particle size and concentration effects on intraparticle diffusivity.” Proc., 3rd Int. Conf., Fundamentals of adsorption, International Adsorption Society, Sothofen, Germany, 965–977.
21.
Wankat, P. C. (1986). Large-scale adsorption and chromatography, Vol. I, CRC, Boca Raton, Fla.
Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 125 • Issue 8 • August 1999
Pages: 705 - 711
History
Received: Jul 22, 1998
Published online: Aug 1, 1999
Published in print: Aug 1999
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.