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This work presents a comprehensive overview of the mechanical-physical parameters of the transport material affecting the vibratory transport. For this purpose, spruce pellets of different lengths, oak rods and spruce crush were tested. The determined parameters were particle size distribution and shape, internal friction, static and dynamic angle of repose. The samples were transported by a patented validation vibrating conveyor. Various settings were used. The results show that by changing the shape, it is possible to reduce friction or resistance as well as energy intensity during transport. It was observed that perfect shapes and lighter particles have lower friction, but a more pronounced bounce. Therefore, it does not form a typical pattern during transport, as in the case of an imperfectly shaped one. There is also included a simulation of the discrete element method. The study shows the possibility of the vibration machine where the material can be conveyed either directionally or sorted. Web of Science 11 1 art. no. 16606

Cooling is an important process during the production of pellets (as post-treatment). The pellet cooling process significantly impacts the quality of the pellets produced and the systematic use of energy. However, the cooling systems currently in use sometimes encounter technical problems, such as clogging of the perforated grids (sieves), the discharge hopper, or pellet degradation may occur. Therefore, a prototype of a new pellet cooling system using a vibrating feeder was tested. The aim of the study is to present a new variation of pellet cooling system using spiral vibration cooler as a possible solution next to a counterflow cooler. The presented system was tested (critically evaluated and discussed) in two design variants. The first variant consists in cooling by chaotic movement of the pellets. The second is then in combination with the chaotic movement of the pellets together with the action of intense air flow using specially placed air hoses. All tests involved pelletization of rapeseed straw. It was found that both cooling system variants could, realistically, be used. However, the variant with an intense air flow was more energy-intensive, a factor which is, however, offset by the higher quality of the pellets. No negative impact of vibrations to pellets quality was occur. Studies provide insight into new usable technologies that do not reduce the efficiency of the process as a result of grate clogging. Web of Science 9 6 art. no. 1060

With the rise of additive technologies, the characterization of metal powders is increasingly required. There is a need to precisely match the properties of metal powders to a specific machine and to ensure highly consistent production. Therefore, the study aims at a detailed characterization of ten metal powders (Metal powder 316 L, Zn, Sn, Al, Cu, Mn, Fe, Bronze, Ti and Mo powder), for which the particle size distribution, morphology, static and dynamic angle of repose and the effective internal friction angle (AIFE) were determined. The AIFE parameter and flow index were determined from three commonly used rotary shear devices: The computer-controlled Ring Shear Tester RST-01. pc, the Brookfield PFT Powder Flow Tester and the FT4 Powder rheometer. The results showed that the values for the device of one manufacturer did not fully correspond to the values of another one. The flow characteristics of the metal powders were quantified from the particle size distribution data, static angle of repose, and AIFE data. According to the particle size distribution and angle of repose (AOR), 50% of the tested metal powders fell into the free-flowing mode. According to the evaluation of AIFE, 20% of the samples fell into the lower area. Based on the flow indexes calculated from the measurements of the shear devices used, 100% (RST-01.pc), 70% (PFT) and 50% (FT4) of the samples were included in the free-flowing category. When comparing the results, attention should be paid not only to the nature of the material, but also to the methodology and equipment used. A comparison of methodologies revealed similarities in the changing behavior of the different metal powders. A comparison of effective angles of AIFE and static AOR was shown, and a hypothesis of the conversion relation was derived. Web of Science 10 1 art. no. 21004