7 Dynamic Simulation of Mechanical Fluid Separation in Solid …
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considers the calculation of sediment build-up and sediment transport. The comparison of dynamic simulations with experiments for finely dispersed particle systems
shows a good conformity.
Finally, the broad applicability of the developed compartment model was demonstrated by transferring the dynamic model of a continuous working decanter to semibatch tubular centrifuges. It can be shown that the deviating process behavior of
tube centrifuges is due to the sediment build-up in the rotor. In contrast to decanter
centrifuges, the accumulated solids remain in the apparatus and thus reduce the flow
cross-section. As a result, the residence time decreases permanently until the sediment occupies the entire rotor. The comparison with experiments for nanoscale silica
also shows a good agreement between simulation and experiment for the temporal
change of product loss and grade efficiency. The developed models are not only suitable for dynamic flowsheet simulation, but also for other applications. For example,
it is conceivable to use dynamic models for MPC or to carry out an optimization
regarding raw material or resource efficiency.
References
1. Kowalczyk, B., Lagzi, I., Grzybowski, B.A.: Nanoseparations: strategies for size and/or shapeselective purification of nanoparticles. Curr. Opin. Colloid Interf. Sci. 16, 135–148 (2011).
https://doi.org/10.1016/j.cocis.2011.01.004
2. Kanarska, Y., Lomov, I., Antoun, T.: Mesoscale simulations of particulate flows with parallel
distributed Lagrange multiplier technique. Comput. Fluids 48, 16–29 (2011). https://doi.org/
10.1016/j.compfluid.2011.03.010
3. Ambler, C.M.: The evaluation of centrifuge performance. Chem. Eng. Prog. 48, 150–158 (1952)
4. Ambler, C.M.: The theory of scaling up laboratory data for the sedimentation type centrifuge.
J. Microb. Biochem. Technol. 1, 185–205 (1959)
5. Leung, W.W.-F.: Industrial Centrifugation Technology. McGraw-Hill, New York (1998)
6. Gleiss, M., Hammerich, S., Kespe, M., Nirschl, H.: Application of the dynamic flow sheet
simulation concept to the solid-liquid separation: separation of stabilized slurries in continuous
centrifuges. Chem. Eng. Sci. 163, 167–178 (2017)
7. Konrath, M., Brenner, A., Dillner, E., Nirschl, H.: Centrifugal classification of ultrafine particles: Influence of suspension properties and operating parameters on classification sharpness.
Sep. Purif. Technol. 156, 61–70 (2015)
8. Romanni Fernández, X., Nirschl, H.: A numerical study of the impact of radial baffles in solid
bowl centrifuges using computational fluid dynamics. Phys. Sep. Sci. Eng. (2010)
9. Romaní Fernández, X., Nirschl, H., Fernández, X.R., Nirschl, H.: Simulation of particles and
sediment behaviour in centrifugal field by coupling CFD and DEM. Chem. Eng. Sci. 94, 7–19
(2013). https://doi.org/10.1016/j.ces.2013.02.039
10. Hammerich, S., Gleiß, M., Nirschl, H.: Modeling and simulation of solid-bowl centrifuges
as an aspect of the advancing digitization in solid-liquid separation. Chemie Ing. Tech. 91,
215–227 (2019)
11. Hammerich, S., Gleiß, M., Kespe, M., Nirschl, H.: An efficient numerical approach for transient
simulation of multiphase flow behavior in centrifuges. Chem. Eng. Technol. 41, 44–50 (2018)
12. Stahl, W.: Fest-Flüssig-Trennung Band II: Industrie-Zentrifugen, Maschinen-und Verfahenstechnik. DRM Press, CH-Männedorf (2004)
13. Skinner, S.J., Studer, L.J., Dixon, D.R., Hillis, P., Rees, C.A., Wall, R.C., et al.: Quantification
of wastewater sludge dewatering. Water Res. 82, 2–13 (2015). https://doi.org/10.1016/j.watres.
2015.04.045
267
considers the calculation of sediment build-up and sediment transport. The comparison of dynamic simulations with experiments for finely dispersed particle systems
shows a good conformity.
Finally, the broad applicability of the developed compartment model was demonstrated by transferring the dynamic model of a continuous working decanter to semibatch tubular centrifuges. It can be shown that the deviating process behavior of
tube centrifuges is due to the sediment build-up in the rotor. In contrast to decanter
centrifuges, the accumulated solids remain in the apparatus and thus reduce the flow
cross-section. As a result, the residence time decreases permanently until the sediment occupies the entire rotor. The comparison with experiments for nanoscale silica
also shows a good agreement between simulation and experiment for the temporal
change of product loss and grade efficiency. The developed models are not only suitable for dynamic flowsheet simulation, but also for other applications. For example,
it is conceivable to use dynamic models for MPC or to carry out an optimization
regarding raw material or resource efficiency.
References
1. Kowalczyk, B., Lagzi, I., Grzybowski, B.A.: Nanoseparations: strategies for size and/or shapeselective purification of nanoparticles. Curr. Opin. Colloid Interf. Sci. 16, 135–148 (2011).
https://doi.org/10.1016/j.cocis.2011.01.004
2. Kanarska, Y., Lomov, I., Antoun, T.: Mesoscale simulations of particulate flows with parallel
distributed Lagrange multiplier technique. Comput. Fluids 48, 16–29 (2011). https://doi.org/
10.1016/j.compfluid.2011.03.010
3. Ambler, C.M.: The evaluation of centrifuge performance. Chem. Eng. Prog. 48, 150–158 (1952)
4. Ambler, C.M.: The theory of scaling up laboratory data for the sedimentation type centrifuge.
J. Microb. Biochem. Technol. 1, 185–205 (1959)
5. Leung, W.W.-F.: Industrial Centrifugation Technology. McGraw-Hill, New York (1998)
6. Gleiss, M., Hammerich, S., Kespe, M., Nirschl, H.: Application of the dynamic flow sheet
simulation concept to the solid-liquid separation: separation of stabilized slurries in continuous
centrifuges. Chem. Eng. Sci. 163, 167–178 (2017)
7. Konrath, M., Brenner, A., Dillner, E., Nirschl, H.: Centrifugal classification of ultrafine particles: Influence of suspension properties and operating parameters on classification sharpness.
Sep. Purif. Technol. 156, 61–70 (2015)
8. Romanni Fernández, X., Nirschl, H.: A numerical study of the impact of radial baffles in solid
bowl centrifuges using computational fluid dynamics. Phys. Sep. Sci. Eng. (2010)
9. Romaní Fernández, X., Nirschl, H., Fernández, X.R., Nirschl, H.: Simulation of particles and
sediment behaviour in centrifugal field by coupling CFD and DEM. Chem. Eng. Sci. 94, 7–19
(2013). https://doi.org/10.1016/j.ces.2013.02.039
10. Hammerich, S., Gleiß, M., Nirschl, H.: Modeling and simulation of solid-bowl centrifuges
as an aspect of the advancing digitization in solid-liquid separation. Chemie Ing. Tech. 91,
215–227 (2019)
11. Hammerich, S., Gleiß, M., Kespe, M., Nirschl, H.: An efficient numerical approach for transient
simulation of multiphase flow behavior in centrifuges. Chem. Eng. Technol. 41, 44–50 (2018)
12. Stahl, W.: Fest-Flüssig-Trennung Band II: Industrie-Zentrifugen, Maschinen-und Verfahenstechnik. DRM Press, CH-Männedorf (2004)
13. Skinner, S.J., Studer, L.J., Dixon, D.R., Hillis, P., Rees, C.A., Wall, R.C., et al.: Quantification
of wastewater sludge dewatering. Water Res. 82, 2–13 (2015). https://doi.org/10.1016/j.watres.
2015.04.045