Feedstock particle size distribution and water content dynamic in a pellet mill production process and comparative sieving performance of horizontal 3.15-mm mesh and 3.15-mm hole sieves

  • Sebastian PaczkowskiEmail author
  • Christian Sauer
  • Anja Anetzberger
  • Marta Paczkowska
  • Michael Russ
  • Marius Wöhler
  • Stefan Pelz
Original Article


Pellet feedstock particle size distribution is the main factor affecting pellet quality. Feedstock samples were obtained from different places in the production process of a commercial pellet mill. Particle size distribution and water content of the sieved particle fractions were analyzed. The results showed an alternation of particle size distribution and water content of the feedstock induced by the processing in the mill. Storage had a balancing effect on the water content distribution between the different particle size classes. Further experiments evaluated the reason for the underrepresentation of the 2.8–3.15-mm fraction in the feedstock. It was found that the major sieving factor for non-spherical wood particles was their width rather than their length, though the aspect ratio was important for the sorting between the 2.8–3.15-mm and the 2.0–2.8-mm sieve fractions. The significant differences between the particle width in the sieve fractions and the distribution of the particle aspect ratio improved when using a 3.15-mm mesh sieve instead of the 3.15-mm hole sieve. This indicates the better sieving performance of the 3.15-mm mesh sieve, which should be considered by pellet manufacturers and researchers investigating pellet feedstock.


Wood flake screening Particle aspect ratio Dry mass distribution Mesh sieve Hole sieve Pellet feedstock 



The authors want to thank the technical staff of the University of Applied Science Rottenburg, Dr. Rainer Kirchhof, Dipl.-Ing. (FH) Carola Lepski, B.Sc. Peter Grammer, and B.Sc. Jodok Braun for their technical support.

Funding information

The work of Dr. Sebastian Paczkowski and M.Sc. Michael Russ was funded by the Bundesministerium für Bildung und Forschung, Germany (Project BiCoLim, grant number 01DN16036), respectively. The work of B.Sc. Christian Sauer was funded by the University of Applied Science Rottenburg, Germany, and the work of Anja Anetzberger was funded by the sawmill Haisch GmbH & Co. KG, Germany.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Sebastian Paczkowski
    • 1
    Email author
  • Christian Sauer
    • 2
  • Anja Anetzberger
    • 1
  • Marta Paczkowska
    • 1
  • Michael Russ
    • 1
  • Marius Wöhler
    • 3
  • Stefan Pelz
    • 1
  1. 1.University of Applied Science RottenburgRottenburgGermany
  2. 2.Department of Conversion Technologies of Biobased Resources, Institute of Agricultural EngineeringUniversity of HohenheimStuttgartGermany
  3. 3.Schellinger KGWeingartenGermany

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