Effect of Die Channel Geometry on the Quality of Pellets Obtained from Biomass

The presented research focuses on assessing the impact of the geometry of the compaction channel on the quality of pellets produced from giant miscanthus, silphium, and sida. Geometry refers to parameters such as <i>L</i>, <i>D</i>, α, and the diameter of the channel, as well the height of the compacting cone. Our analysis covered the pressure compaction process of monocotyledonous and dicotyledonous perennials, considered a valuable source of biomass for energy purposes. These species are the subject of processing research; they are promising, easy to grow and, crucially, non-invasive. The results of the research indicated the optimal configurations for each plant. For miscanthus: <i>D</i> = 12 mm, α = 10°, <i>L</i> = 13 mm, and compaction pressure <i>P</i> = 245 MPa; for <i>D</i> = 10 mm, <i>α</i> = 10°, <i>L</i> = 22 mm, and <i>P</i> = 185 MPa. For silphium: <i>D</i> = 12 mm, <i>α</i> = 20°, <i>L</i> = 21 mm, <i>P</i> = 50 MPa, and for <i>D</i> = 10 mm: α = 20°, <i>L</i> = 26 - 27 mm, and <i>P</i> = 42 MPa. For Virginia mallow: <i>D</i> = 12 mm, <i>α</i> = 10°, <i>L</i> = 5 mm, and <i>P</i> = 237 MPa, or with a diameter of 10 mm: <i>α =</i> 30°, <i>L</i> = 23 mm, and <i>P</i> = 58 MPa.