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Research was carried out into the impact of the content of wheat flour in a mixture with chopped wheat straw and the humidity of this material on the hardness of the pellet obtained from this raw material. The maximum content of wheat flour was 9.6% of the dry matter of the raw material, and the humidity of the raw material was 11.6, 25.7 and 36.0%. An increase of wheat flour content in the whole range examined considerably increased the pellet hardness, while an increase of humidity content in the raw material had an impact on increased hardness up to 25.7% only.

Influence of wastes generated during juice production: apple, carrot and red beet, added to barley straw, on density of pellet mass, pellet hardness, ash content and calorific value was assessed. Dry mass content of additives in the substrate to pellet production was: 0, 10, 20 and 30% of the mixture weight. The relative humidity of the raw material was: 17.0, 19.5 and 22%. Higher percentages of additives and higher moisture content in the raw materials increased the hardness and density of the pellet. The contents of natural polymers such as lignin, hemicellulose and cellulose were determined in primary materials used to prepare substrate and in pellet. Changes in the determination of these substances was observed as a result of the granulation process.

This article explains the physical features of various methods of compaction, primarily for end of life vehicle (ELV) bodies coming from ELV processors. By EU directive 2000/53/EC it is mandatory for all EU members to meet the reuse of 95 % of the old vehicle weight. It means that the vehicles have to be decomposed completely – metal shells freed from all the components like interior trim, rubber sealing, glass, all the liquids, seats tanks and other hard metal components like drive-train, engine etc. It follows that pressing machines used for compressing whole vehicles today, are overpowered, with high energy demand, robust structures and heavy weight. Hence it makes sense to concentrate on comparison of pressing methods and choosing the most energy efficient one and the designing a new device, if necessary. This device is aimed for operation in Slovak Republic but also usable in other countries with same or similar requirements such as optimized system for processing of car bodies, mobile concept and modularity of the whole mobile modular disintegration complex consisting of a pressing machine, shears and shredder. Car body structure

The contribution deals with the trimming of beef cattle hooves by means of a new method, specifically with a liquid water jet. Present methods of trimming hooves are outdated; almost nowhere are new modern technologies used for this purpose. The use of more contemporary methods would enable a reduction in the high labour demands to accomplish this task. But the main advantage of this new method is increasing so-called animal WELFARE. Present-day methods which are performed mechanically are always stressful, and many times also painful, for the animal. In the article we will specifically focus on the possibility of trimming the hooves of beef cattle by means of a water jet. The original research was focused on the size of the basic parameters such as pressure, flow, nozzle diameter and cutting time. The results of this initial research serve as a step towards further research, whose goal will be the design and testing of complex equipment for trimming beef cattle hooves by cutting with a liquid water jet.

An article is about mechanical effect of the physic-mechanical material properties on the radial pressure in the compression chamber during the compacting process of wood. Some general methods that describe the transformation process of axial pressure into the radial pressure are shown, As well as the mathematical or experimental methods specifying dependencies and physical conditions. Mathematical finite element method in this area is very useful, but rarely used. Common problems using FEM are the proper definition of the physical material properties in a particular stage of compaction. Material properties are greatly influenced by a number of factors such as moisture, fraction size, chemical composition, current temperature, radial macro structure, axial macrostructure, current pressure and others. The chamber material and the manufacturing processes or the state of wear has an impact on the physical conditions. In terms of tensile elastic deformations, these complex effects reflect and can be merged into several properties. The conversion of axial to radial pressure indicates that some properties of the compacted material have a major impact on the process, such as friction between material and chamber, elastic modulus and Poisson's ratio. The geometry of the pressing chamber also has a significant impact. This paper does not deal so much with the pressing chamber geometry but more so with the characteristics embodied in experimentally measurable quantities. The measurement of these properties in combination with the application of FEM methods proves to be a highly progressive method for understanding the compaction process and the engineering design of compaction machines for the production of briquettes and pellets. The article urges further examination and measurement of a wider range of material properties in the densification process.

This contribution describes developments in the area of plastic recycling aimed at the reuse of waste materials for the manufacture of a useful product. Throughout development of the concept “modular flood barrier structure”, the recovery of plastic materials was assessed, primarily, plastic waste from automobiles and industry. The investigators filed a utility model application, no. SK 5847 Y12, entitled “Modular flood barrier structure”. Terms of the type and composition of source material, polypropylene (PP) and polyethylene (PE) were the materials chosen. The article describes the theoretical analysis of the proposed barriers as a starting point for a design and technological design.

The article deals with a thermal decomposition of vineyard pruning waste. The samples were tested by means of thermogravimetry and differential scanning calorimetry in the flow of air and nitrogen. Thermal gravimetric analyses were performed up to a temperature of 650°C and differential scanning calorimetry up to a temperature of 600°C. The heating rates were 2°C.min−1, 5°C.min−1, 10°C.min−1, 15°C.min−1 and 20°C.min−1 in both cases. Values of activation energies were subsequently calculated from the obtained results using various methods. The maximum mass loss of the samples was observed in the temperature range from 297.5°C to 319.3°C in the case of test with air and in the case of test with nitrogen in the range between 330°C and 367.3°C. The values of activation energy of thermal decomposition in the air were higher than the values in the case of nitrogen atmosphere.

The shredding process has not been sufficiently investigated for the design of better, energy and material saving shredding machines. In connection with present-day concern about the environment, ecology, energy saving, recycling, and finding new sources of energy, we need to look at the design of shredding machinery, the efficiency of the machines that we using, and ways of improving them to save electric energy for their operation. This paper deals with sizing and designing shredding machines from the point of view of energy consumption and optimization for specific types of processed material.

This paper focuses on the structural design of screw tools in briquetting presses used for the production of solid, high quality, bio fuels. The primary objective is to analyse the screw tool geometry and determine a procedure for its design, specifically the theory involved with the pressing tool and force relations which are necessary for the verification of the proposed tool geometry and its strength analysis. In designing the main drive of the press, procedures for determining frictional performance of the screw press are used. Familiarity with the above mentioned procedures forms the basis for research into new tools in screw briquetting presses that will improve the service life and competitiveness of the technology.