Separation of Tenebrio molitor larvae from unwanted residues, like frass, feed or exuviae is a key process step for an industrial scale plant. One method to separate larvae from residues is using a zigzag air classifier. For designing and for an efficient operation of a zigzag air classifier, the terminal velocity is a key parameter to separate larvae from different residues with a high separation sensitivity. In this work, the terminal velocities of different larvae sizes are evaluated analytically, numerically and experimentally. For this, the sizes of 3 week to 12 week old larvae were used to calculate and simulate the terminal velocity. To validate the results, an experiment was carried out and compared with the analytical and numerical data. For this, a model for T. molitor larvae was designed to calculate the surface and volume of a larva to produce equivalent spheres with the same physical properties as a real larva. The results are showing similar curves with terminal velocities from 5 m/s for young larvae (3 weeks old) to 12 m/s for older larvae (12 weeks old). The deviations between each method are 1 m/s for smaller larvae and 1.5 m/s for bigger larvae. In further experiments and simulations, approaches with calculation methods for non-spherical particles are necessary to achieve results closer to reality due to the cylindrical shape of T. molitor larvae.
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Banjac, V., Pezo, L., Pezo, M., Vukmirović, Ð., Čolović, D., Fišteš, A. and Čolović, R., 2017. Optimization of the classification process in the zigzag air classifier for obtaining a high protein sunflower meal – chemometric and CFD approach. Advanced Powder Technology 28: 1069-1078. https://doi.org/10.1016/j.apt.2017.01.013.
Barderas, A.V. and Rodea, S.G., 2016. How to calculate the volumes of partially full tanks. International Journal of Research in Engineering and Technology 5: 1-7. https://doi.org/10.15623/ijret.2016.0504001.
Baur, A., 2020. Asymmetrischer Zickzack-Sichter mit einer angepassten Geometrie zur schonenden Abtrennung von empfindlichen Partikeln: DE202020000807U1. Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany. Available at: https://patents.google.com/patent/DE202020000807U1/de#patentCitations.
DeCarlo, P.F., Slowik, J.G., Worsnop, D.R., Davidovits, P. and Jimenez, J.L., 2004. Particle morphology and density characterization by combined mobility and aerodynamic diameter measurements. Part 1: theory. Aerosol Science and Technology 38: 1185-1205. https://doi.org/10.1080/027868290903907.
Dennis, S.C.R., Singh, S.N. and Ingham, D.B., 1980. The steady flow due to a rotating sphere at low and moderate Reynolds numbers. Journal of Fluid Mechanics 101: 257-279. https://doi.org/10.1017/S0022112080001656.
Dietrich, W.E., 1982. Settling velocity of natural particles. Water Resources Research 18: 1615-1626. https://doi.org/10.1029/WR018i006p01615.
Hagemeier, T., Glöckner, H., Roloff, C., Thévenin, D. and Tomas, J., 2014. Simulation of multi-stage particle classification in a zigzag apparatus. Chemical Engineering & Technology 37: 879-887. https://doi.org/10.1002/ceat.201300670.
Haider, A. and Levenspiel, O., 1989. Drag coefficient and terminal velocity of spherical and nonspherical particles. Powder Technology 58: 63-70. https://doi.org/10.1016/0032-5910(89)80008-7.
Kaiser, F., 1963. Der Zickzack-Sichter – ein Windsichter nach neuem Prinzip. Chemie Ingenieur Technik – CIT 35: 273-282. https://doi.org/10.1002/cite.330350405.
Kröncke, N., Baur, A., Böschen, V., Demtröder, S., Benning, R. and Delgado, A., 2020. Automation of insect mass rearing and processing technologies of mealworms (Tenebrio molitor). In: Mariod, A.A. (ed.) African edible insects as alternative source of food, oil, protein and bioactive components. 1st ed. Springer, Cham, Switzerland, pp. 123-139. https://doi.org/10.1007/978-3-030-32952-5_8.
Morrison, F.A., 2013. An introduction to fluid mechanics. Cambridge University Press, Cambridge, United Kingdom, 948 pp. https://doi.org/10.1017/CBO9781139047463.
Morsi, S.A. and Alexander, A.J., 1972. An investigation of particle trajectories in two-phase flow systems. Journal of Fluid Mechanics 55: 193. https://doi.org/10.1017/S0022112072001806.
Peirce, J.J. and Wittenberg, N., 1984. Zigzag configurations and air classifier performance. Journal of Energy Engineering 110: 36-48. https://doi.org/10.1061/(ASCE)0733-9402(1984)110:1(36).
Roloff, C., Mann, H., Tomas, J. and Thévenin, D., 2015. Flow investigation of a zigzag air classifier. Conference on Modelling Fluid Flow (CMFF’15). In: The 16th International Conference on Fluid Flow Technologies, September 1–4, 2015, Budapest, Hungary. Available at: https://www.researchgate.net/profile/christoph-roloff/publication/321051894_flow_investigation_of_a_zigzag_air_classifier/links/5a0ada890f7e9b0cc02356e3/flow-investigation-of-a-zigzag-air-classifier.pdf.
Saffman, P.G., 1965. The lift on a small sphere in a slow shear flow. Journal of Fluid Mechanics 22: 385-400. https://doi.org/10.1017/S0022112065000824.
Turck, D., Castenmiller, J., de Henauw, S., Hirsch-Ernst, K.I., Kearney, J., Maciuk, A., Mangelsdorf, I., McArdle, H.J., Naska, A., Pelaez, C., Pentieva, K., Siani, A., Thies, F., Tsabouri, S., Vinceti, M., Cubadda, F., Frenzel, T., Heinonen, M., Marchelli, R., Neuhäuser-Berthold, M., Poulsen, M., Prieto Maradona, M., Schlatter, J.R., van Loveren, H., Ververis, E. and Knutsen, H.K., 2021. Safety of dried yellow mealworm (Tenebrio molitor larva) as a novel food pursuant to Regulation (EU) 2015/2283. EFSA journal 19: e06343. https://doi.org/10.2903/j.efsa.2021.6343.
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Separation of Tenebrio molitor larvae from unwanted residues, like frass, feed or exuviae is a key process step for an industrial scale plant. One method to separate larvae from residues is using a zigzag air classifier. For designing and for an efficient operation of a zigzag air classifier, the terminal velocity is a key parameter to separate larvae from different residues with a high separation sensitivity. In this work, the terminal velocities of different larvae sizes are evaluated analytically, numerically and experimentally. For this, the sizes of 3 week to 12 week old larvae were used to calculate and simulate the terminal velocity. To validate the results, an experiment was carried out and compared with the analytical and numerical data. For this, a model for T. molitor larvae was designed to calculate the surface and volume of a larva to produce equivalent spheres with the same physical properties as a real larva. The results are showing similar curves with terminal velocities from 5 m/s for young larvae (3 weeks old) to 12 m/s for older larvae (12 weeks old). The deviations between each method are 1 m/s for smaller larvae and 1.5 m/s for bigger larvae. In further experiments and simulations, approaches with calculation methods for non-spherical particles are necessary to achieve results closer to reality due to the cylindrical shape of T. molitor larvae.
All Time | Past Year | Past 30 Days | |
---|---|---|---|
Abstract Views | 81 | 81 | 30 |
Full Text Views | 5 | 5 | 2 |
PDF Views & Downloads | 2 | 2 | 2 |