Filters

2022 - 20232

More filters

20232
Reset filters

Settings

Author: Dittrich, Christian × Publisher: Basel : MDPI ×

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Influence of Processing Parameters on Fibre Properties during Twin-Screw Extrusion of Poplar Wood Chips
    (Basel : MDPI, 2022) Dittrich, Christian; Pecenka, Ralf; Selge, Benjamin; Ammon, Christian; Kruggel-Emden, Harald
    For sustainable agriculture, the contentious input of peat in growing media needs to be replaced by a substitute with the best possible water-holding capacity (WHC). Wood from fast growing poplar trees, cultivated in short rotation coppices (SRC), is a suitable alternative if it is processed correctly in a twin-screw extruder. The processing parameters, such as the aperture setting of the extruder, moisture content, and specific energy demand (SED), during twin-screw extrusion, as well as their influence on fibre properties such as WHC and particle size distribution, are investigated. SRC-poplar wood chips from clone Max3 are the raw material used for this research. As a result, the best volume-based WHC (75%) at −1 kPa suction tension was achieved for dry extruded wood chip fibre at an aperture setting of 15 mm and an SED of 340 kWh*t−1. The smallest SED of 140 kWh*t−1 was measured at apertures of 35 mm and 40 mm, which resulted in a volume-based WHC of approximately 30% and a dry matter mass flow during processing of 0.289 t*h−1 (40 mm). The particle size distribution of semi-dry wood chips has the highest fine fraction as well as the smallest coarse fraction. Conclusively, poplar wood can be processed fresh and dry into fibre at an acceptable SED, which results in an acceptable WHC.
  • Thumbnail Image
    Item
    Effects of Feeding Speed and Temperature on Properties of Briquettes from Poplar Wood Using a Hydraulic Briquetting Press
    (Basel : MDPI, 2023) Orisaleye, Joseph I.; Jekayinfa, Simeon O.; Dittrich, Christian; Obi, Okey F.; Pecenka, Ralf
    Biomass has a high potential to contribute towards resolving the energy deficit. Processing biomass into solid fuels enhances its use in various bioenergy conversion technologies. The quality of densified biomass depends on several variables. The investigation of the effect of densification parameters on briquette quality is necessary for process optimization. This study investigates the influence of die temperature (100, 120, 140 °C) and feeding speed (2.4, 2.9, 3.3 mm s−1) on the quality of briquettes produced from poplar using a hydraulic biomass briquetting machine. The density of the briquettes ranged between 746.7 and 916.8 kg m−3, the mechanical durability ranged from 97.4 to 98.4%, and the water resistance index was between 91.6 and 96.1%. The results show that the temperature was statistically significant (p < 0.05) on the density, mechanical durability and water resistance of biomass briquettes. The feeding speed was statistically significant (p < 0.05) on the density and water resistance. The interaction of temperature and feeding speed was statistically significant (p < 0.05) on all properties considered. The results obtained in this study are useful for optimizing the quality of briquettes produced using the hydraulic piston press.