Friction and Shear Properties of Pine Biomass and Pellets

Abstract

Knowledge on the mechanical properties of granular biomass is important for the design and efficient operation of equipment used for handling, storage, and processing. Their mechanical properties are used as a measure of material quality. In this study, the mechanical properties of granular biomass obtained from pines (sawdust, shavings, long shavings, and pellets) were determined under a moisture content range of 10–50%. The coefficient of sliding friction µ of four construction materials was determined using a 210-mm-diameter direct shear tester (Jenike’s shear box). To measure the shear resistance of the biomass materials (represented as torque T), a prototype vane tester was constructed. The characteristics of shear resistance with respect to time T(t) were determined for material samples under normal pressure p ranging from 5 to 30 kPa and a vane rotation rate of 3 rpm. Measurements were performed for five geometries of the rotor, reflecting typical deformation conditions encountered in the processing of granular biomass. The coefficient of sliding friction was found to be affected by the type of material, moisture content, and normal compressive pressure. Depending on the biomass material, the highest µ, which ranged from 0.50 to 0.62, was obtained for black steel, whereas the lowest µ, which ranged from 0.27 to 0.52, was obtained for aluminum. The lowest coefficient of sliding friction was observed for dry materials and high normal pressure. The torque T was observed to be affected by the rotor shape, material, normal pressure, and moisture content. The parameters presented provide information useful for the design of transport equipment and processing of granular wood biomass.

Effect of the Drying Method of Pine and Beech Wood on Fracture Toughness and Shear Yield Stress

“…No significant differences were noticed in the case of pine wood for both the normalized fracture toughness R * ⊥ and normalized shear yield stress τ * γ⊥. The evident effect of wood density ρ [54,55] can be compensated by normalizing values of resulting mechanical parameters [41]. Diverse algorithms can be implemented for the data unification and further non-biased interpretation.…”

Determination of the Influence of Mechanical Properties of Capsules and Seeds on the Susceptibility to Feeding of Mononychus pubctumalbum in Endangered Plant Species Iris aphylla L. and Iris sibirica L.

“…Technologies based on various types of sensors are now widely used in many fields of both industry and science. The most common types are optical sensors used to determine the content and concentration of gases or liquids [1,2], temperature sensors to measure the course of thermal processes [3,4], humidity sensors to determine the humidity level in studied environments [3,5], electrochemical sensors to detect volatile organic compounds in raw materials and food products [6,7], or force sensors to measure the mechanical properties of raw materials and products of plant origin [4,[8][9][10]. Sensors are increasingly being used in precision agriculture, which has recently been developing very quickly, also with the use of information technologies and other techniques [11][12][13].…”

“…Morphological traits and mechanical properties of I. aphylla and I. sibirica seed capsules and seeds analyzed in June(6) and September(9).Capsule max load (N)-average maximum force of seed capsule puncture. Seed max load (N)-average maximum force of seed puncture.…”

Possibilities for obtaining pellets by single-screw extrusion of biomass from black pine (Pinus nigra Arn.)

“…Renewable natural sources, including waste raw materials from the timber and processing industry, could be used as an alternative energy source [1]. Their utilization was in granular form, which created preconditions for disruption of the flow due to adhesion and the appearance of cracks [2][3][4].…”

“…The density of the obtained granules was an essential parameter for evaluating the mechanical characteristics, as it also determines the pressure used to obtain the pellets [2,8]. New conditions are created during the increase of the pellet's density to create close interaction between the system's components.…”