11 Experimental Study and Modelling of Particle …
409
5 Conclusion and Perspectives
The zigzag air classifier is a device of high practical importance for a variety of
industrial applications. Additionally, the processes controlling separation in the
zigzag channel are extremely interesting from a fundamental point of view, since
they highlight the importance of coupled aspects (modification of the turbulent flow
induced by the particles; particle-particle and particle-wall collisions; particle swarm
effects…). In this combined study, theoretical developments, systematic experiments,
and numerical simulations relying on different approaches have been combined to
elucidate the controlling parameters and to develop reduced models, suitable for integration into simulation platforms like DYSSOL. It appears that, after proper model
fitting, a good agreement can be obtained between measurement data and model
predictions. Nevertheless, the large differences still found between experiments and
simulations reveal the need for further studies before fully predictive numerical
studies of practical systems become possible with standard computational resources.
Acknowledgements This work was part of the German priority program SPP 1679 entitled
“Dynamische Simulation vernetzter Feststoffprozesse” (“Dynamic simulation of interconnected
solids processes”) that was financially supported by the Deutsche Forschungsgemeinschaft (DFG),
Germany.
References
1. Stebbins, A.H.: Air classifier. US-Patent 1861248 (1930)
2. Kaiser, F.: Der Zickzack-Sichter – ein Windsichter nach neuem Prinzip. Chem. Ing. Tech.
35(4), 273–282 (1963)
3. Fastov, B.N., Valuskii, P.F., Lebedev, V.N., Oskalenko, G.N.: Testing of the zigzag classifier
for granulated materials. Chem. Pet. Eng. 11(5), 477–479 (1975)
4. Friedländer, T., Kuyumcu, H.Z., Rolf, L.: Untersuchung zur Sortierung von PET-Flakes nach
der Teilchenform. Aufbereitungs Tech. 47(8), 24–38 (2006)
5. Senden, M.M.G.: Stochastic models for individual particle behavior in straight and zig zag air
classifiers. PhD, Technical University Eindhoven (1979)
6. Furchner, B. Zampini, S.: Air classifying. In: Ullmann’s Encyclopedia of Industrial Chemistry,
vol. 2, pp. 215–234. Wiley-VCH, Weinheim (2012)
7. Worrell, W.A., Vesilind, P.A.: Testing and evaluation of air classifier performance. Resour.
Recovery Conserv. 4, 247–259 (1979)
8. Rosenbrand, G.G.: The separation performance and capacity of zigzag air classifiers at high
particle feed rates. PhD, Technical University Eindhoven (1986)
9. Vesilind, P.A., Henrikson, R.A.: Effect of feed rate on air classifier performance. Resour.
Conserv. 6, 211–221 (1981)
10. Biddulph, M.W., Connor, M.A.: A method of comparing the performance of air classifiers.
Resour. Conserv. Recycl. 2, 275–286 (1989)
11. Tomas, J., Gröger, T.: Mehrstufige turbulente Aerosortierung von Bauschutt. Aufbereitungs
Tech. 40(8), 379–386 (1999)
12. Tomas, J.: Gravity separation of particulate solids in turbulent fluid flow. Part. Sci. Technol.
22, 169–188 (2004)
409
5 Conclusion and Perspectives
The zigzag air classifier is a device of high practical importance for a variety of
industrial applications. Additionally, the processes controlling separation in the
zigzag channel are extremely interesting from a fundamental point of view, since
they highlight the importance of coupled aspects (modification of the turbulent flow
induced by the particles; particle-particle and particle-wall collisions; particle swarm
effects…). In this combined study, theoretical developments, systematic experiments,
and numerical simulations relying on different approaches have been combined to
elucidate the controlling parameters and to develop reduced models, suitable for integration into simulation platforms like DYSSOL. It appears that, after proper model
fitting, a good agreement can be obtained between measurement data and model
predictions. Nevertheless, the large differences still found between experiments and
simulations reveal the need for further studies before fully predictive numerical
studies of practical systems become possible with standard computational resources.
Acknowledgements This work was part of the German priority program SPP 1679 entitled
“Dynamische Simulation vernetzter Feststoffprozesse” (“Dynamic simulation of interconnected
solids processes”) that was financially supported by the Deutsche Forschungsgemeinschaft (DFG),
Germany.
References
1. Stebbins, A.H.: Air classifier. US-Patent 1861248 (1930)
2. Kaiser, F.: Der Zickzack-Sichter – ein Windsichter nach neuem Prinzip. Chem. Ing. Tech.
35(4), 273–282 (1963)
3. Fastov, B.N., Valuskii, P.F., Lebedev, V.N., Oskalenko, G.N.: Testing of the zigzag classifier
for granulated materials. Chem. Pet. Eng. 11(5), 477–479 (1975)
4. Friedländer, T., Kuyumcu, H.Z., Rolf, L.: Untersuchung zur Sortierung von PET-Flakes nach
der Teilchenform. Aufbereitungs Tech. 47(8), 24–38 (2006)
5. Senden, M.M.G.: Stochastic models for individual particle behavior in straight and zig zag air
classifiers. PhD, Technical University Eindhoven (1979)
6. Furchner, B. Zampini, S.: Air classifying. In: Ullmann’s Encyclopedia of Industrial Chemistry,
vol. 2, pp. 215–234. Wiley-VCH, Weinheim (2012)
7. Worrell, W.A., Vesilind, P.A.: Testing and evaluation of air classifier performance. Resour.
Recovery Conserv. 4, 247–259 (1979)
8. Rosenbrand, G.G.: The separation performance and capacity of zigzag air classifiers at high
particle feed rates. PhD, Technical University Eindhoven (1986)
9. Vesilind, P.A., Henrikson, R.A.: Effect of feed rate on air classifier performance. Resour.
Conserv. 6, 211–221 (1981)
10. Biddulph, M.W., Connor, M.A.: A method of comparing the performance of air classifiers.
Resour. Conserv. Recycl. 2, 275–286 (1989)
11. Tomas, J., Gröger, T.: Mehrstufige turbulente Aerosortierung von Bauschutt. Aufbereitungs
Tech. 40(8), 379–386 (1999)
12. Tomas, J.: Gravity separation of particulate solids in turbulent fluid flow. Part. Sci. Technol.
22, 169–188 (2004)