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Dynamic testing to determine rheological characteristics of moist food powders (semolina, coarse wheat flour, potato starch) was carried out using a powder rheometer of a new construction. The unique feature of the rheometer is that scale of shearing was confined to the thickness of shearing band of powder bed only. It was found that flow pattern of moistened samples was noticeably and diversely affected by both moisture content (varying in the range of 0-15% w/w) and shear rate. The observed changes showed statistical significance p<0.01 in all trials carried out. What is noteworthy about the conducted research is that at some shear rate values, the shear stress of the bed reached the maximum for specific moisture content levels, irrespective of particle size of the bed.

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The objective of the reported project was to produce wood agglomerates from popular East European species to determine their strength and combustion properties. Closed-die pellets were produced from sawdust of six types of wood common on the East European market: pine, willow, oak, poplar, birch, and beech. The properties of pellets, determined by the type of wood, were influenced by the compaction pressure and the moisture content of the sawdust. The highest average pellet density was obtained for oak sawdust, while the lowest density was obtained for poplar pellets. Expansion of pellets after removing from the die was found to be dependent on the wood species, and as expected, on compaction pressure. The pellet expansion increased after 2 h of conditioning in the laboratory and with an increase in moisture content. The highest and the smallest strength were obtained for oak pellets and for birch sawdust, respectively. The strength of the pellets increased by more than 100% with an increase in the compaction pressure from 60 MPa to 120 MPa. The average strength decreased by 65% with increasing moisture content. For all tested materials, drop resistance remained at a high level, acceptable in industrial practice. The highest calorific value of 18.97 MJ/kg was obtained for pine pellets. The highest ash value of 1.52% was obtained for willow pellets and the lowest value of 0.32% for pine pellets.