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This manuscript concentrates on the relationship between pellets quality, which is represented by the pellets physical properties, and the input composition of raw material. The main aim of this study is to determine the relationship between the raw material composition, which influences the pellets quality and the pellets quality indicators - physical properties of pellets. During the biomass densification also the raw material properties significantly influences the final solid biofuels quality. Therefore the raw material composition represented by two basic raw material mixtures (spruce sawdust/straw and spruce sawdust/bark) each on three levels of ratios (95/5; 90/10 and 80/20) were investigated. Effect of mentioned raw material mixtures on pellets bulk density, mechanical durability, abrasion, particle density and hardness was determined. Research findings presented in this paper are based on a realized experimental research which was done on Faculty of Mechanical Engineering STU in Bratislava. This experimental research was a logical result of and based on authors practical experience and wide theoretical analyses of selected variables influence. Described experimental research was realized by real pelleting machine which is a part of semi-production pelleting plant on Faculty of Mechanical Engineering STU in Bratislava.The experimental findings presented here are showing the importance of mentioned variables and parameters during the densification process. [ABSTRACT FROM AUTHOR]

In additive manufacturing field are many technologies and devices which could be included in such area. Basic difference between conventional and additive manufacturing is the way how the surfaces of final part are created. In conventional subtractive manufacturing we have to remove material from block of raw material of semi-product to reach final shape. For additive manufacturing is typical that we adding material, mostly layer by layer to build final shape of model. Most common and available additive manufacturing technology is Fused Deposition Modeling, or simply said deposition of semi-melted thermoplastic layer by layer. Presented paper deal with Fused Deposition Modeling (FDM) technology, the core of which is the manufacture models and components from thermoplastic polymers by deposition single fibers of semi-molted plastic material layer by layer. The article focuses on the results of research for testing of manufactured specimens by FDM technology. As technical plastic are mostly used polymers as ABS, Nylon, PET or others. There are even brand new plastics, based on typical polymers as ABS plastic, but they are filled with additives to improve their mechanical properties and also behavior of material during deposition of after the production process. ABS plastic is predisposed to bend and warp during the process or even after production when the final model is getting cold. These new materials eliminate this character. This research paper deals with mechanical testing of specimens produced from special class of ABS plastic, to bring the knowledge what are the properties of new material compare to conventional ABS material. There is designed full factor experiment, described the testing process and also evaluation of measured values by statistical methods. [ABSTRACT FROM AUTHOR]

During the biomass densification can be recognized various technological variables and also material parameters which significantly influences the final solid biofuels quality. The paper deals with the experimental research of the relationship between technological variables and material parameters during densification of acacia wood sawdust. The main goal of presented experimental research is to determine the relationship between compression pressure, pressing temperature and raw material moisture content and particle size during densification of acacia wood sawdust. Research findings presented in this paper are based on a realized experimental research which was done on Faculty of Mechanical Engineering STU in Bratislava. This experimental research was a logical result of and based on authors practical experience and wide theoretical analyses of selected variables influence. Described experimental research was realized by single-axis densification. This paper describes also the design of experiment (DOE) and evaluation methodology for this experimental plan in order to determine the influence of technological variables and material parameters on a final biofuels density which mainly represents the biofuels quality. This contribution discusses the analysis of experimental process, its individual steps and their subsequent DOE leading to the development of a mathematical model that will describe this process. The experimental findings presented here are showing the importance of mentioned variables and parameters during the densification process. [ABSTRACT FROM AUTHOR]

Processing the waste paper produces huge amounts of waste - papermaking sludge. This kind of waste includes around 50 % of inorganic material and high proportion of water. Its current economic recovery is very limited, which affects the overall efficiency of recycling paper. However, the elementary and chemical composition has a high potential for wider and more economically efficient use in various industrial fields. The object of this paper is research of composition and physical properties of such sludge from old paper recycling. The work analyzes the possibilities of the sludge material recovery and aims to develop a new product for the construction industry - building plates with different physical properties and their areas of application. Realized experimental research has shown high potential of material recovery of this waste. Research results show that the new product developed on the basis of the papermaking sludge achieves excellent mechanical properties. Thanks to this way, the material recovery of sludge from old paper recycling obtains not only economically efficient new product but also environmental benefits. [ABSTRACT FROM AUTHOR]

3D printing is very popular technique for producing of models. There are few possible technologies used in 3D printing. The most popular is Fused Deposition Modeling (FDM) technology which use plastic filaments in the form of plastic wire. The first used material type was ABS plastic material. But now we have really wide spectrum of materials mostly based on polymers, also nylon or composite materials. In this group we can find also PLA plastic, what is biodegradable polymer produced from starch of corn, potatoes and others agricultural plants. Even if the polymer is produced from starch, the material properties of 3D models produced by FDM technology are comparable with others conventional polymers. This paper deal with material properties of PLA material based on prepared and realized experiments. [ABSTRACT FROM AUTHOR]

In this paper, we will present the research findings the impact of the particle size in pressing chamber during densification of wooden briquettes. In general during in the biomass densification process technological and material variables influence this process and thus the final briquettes quality. The impact of compression pressure and compression temperature is known very well. The main goal of presented experimental research is to determine the impact and relationship between particle size and pressing conditions. This variable influencing also lonely raw material treatment, densification and also pressing forces distribution into the pressing chamber. The abovementioned impact can be observed during densification in the quality indicators. Research findings presented in this paper are based on a realized experimental research which was done on Faculty of Mechanical Engineering STU in Bratislava. This experimental research was a logical result of and based on authors practical experience and wide theoretical analyses of selected parameters impact. Experimental research findings were obtained using single-axis densification. The influence of the particle size interacting with compression pressure on the final density, and thus also on acting forces size was determined. The experimental research findings presented here should prove the significance in briquette production and also in the engineering of densification machines. [ABSTRACT FROM AUTHOR]

Rapid Prototyping Systems are widely used in every field of our industry. For model prototyping from plastic material are used Fused Deposition Modeling, one of Rapid Prototyping Technology. This systems are working with plastic wires and typical plastic material is ABS (Acrylonitrile butadiene styrene). But there is also the ecological alternative produced from natural sources, which is more acceptable for our environment. Such a plastic material is PLA (Polylactic acid or Polylactide). Rapid Prototyping Systems can be considered as Computer Aided Systems facilitating the designing process. The aim of this paper is to show possibility of use ecological PLA plastic for production of 3D models by Fused Deposition Modeling, which is one of Rapid Prototyping technology. The paper describe also mechanical properties of PLA plastic models with comparison to typical ABS plastic widely used in 3D printing. [ABSTRACT FROM AUTHOR]

Disintegration of biomass is one of various preparation processes for biomass processing before its final treatment (production of briquettes or production of pellets). Selection of suitable machine is same important as correct selection of the tool for disintegration. When we change the tool, we can rapidly decrease or increase load of machine, respectively decreasing or increasing of force which is necessary for material disintegration. The same is influence of material type, size of input and also output fraction. From this reason we should to know what are demands for material processing and what is the influence of parameters change and change of disintegrative tool geometry to disintegration process. The aim of following paper is to describe the method for selection of tool for wood biomass disintegration on two-rotor slow-running device. The presented results were achieved based on research which is realized on authors workplace. [ABSTRACT FROM AUTHOR]

Many technological factors (size fraction, moisture content, and others) have major effect on the densification process of biomass to the form of high-grade solid biofuel. The basic parameter describing the densification process of particulate matter is its compressibility, quantified by the coefficient of compressibility. Knowing this coefficient for a specific material like wood sawdust is a basic prerequisite for the application of compressibility equations describing the densification process, and for calculating the workload in the production process of high-grade solid biofuel. This paper deals with a methodology for determining the compressibility factor for sawdust on the basis of experiments to quantify pine sawdust. The experiments were performed in two stages. The first stage was an experimental investigation of the influence of size fraction and moisture content on the final compressibility of pine sawdust. High-pressure binderless densification of pine processing residues in the form of sawdust was studied. A piston-and-die process was used to produce densied briquettes under room temperature and at pressure up to 159 MPa. The results show the behaviour of the pressure load when the parameters of the particulate matter are changed. In the second stage, the experiments were evaluated and optimized to achieve minimum energy input of the process and a maximum degree of densification. The research results will be used to develop new technologies and machinery for effective biomass densification to achieve a high-grade solid biofuel. [ABSTRACT FROM AUTHOR]

In this article, we will present the impact of two most important technological parameters (compacting pressure and pressing temperature) on final wooden briquettes quality. Conditions in pressing chamber during densification can significantly impact the resulting briquettes quality which is evaluated by density. In the introduction, we present which parameters have the significant impact on briquettes densification. An experiment results and findings which are showed in this paper, described the detected impact of monitored parameters at densification of pine and also oak sawdust. Experiment was done in our department in laboratory conditions on our experimental pressing stand. By pressing conditions setting we will be able to achieve the suitable briquettes density with respect of characters and behaviors of pressed type of material. We will present also possibility that from experiment results can be designed mathematical model. This model can be used for prediction of briquettes density at various pressing conditions for given settings and materials. [ABSTRACT FROM AUTHOR]

The paper discusses future experiments at super B factories. It presents the physics motivation and the tools, accelerators and detectors, and reviews the status of the two projects, SuperKEKB/Belle-II in Japan and SuperB in Italy. [ABSTRACT FROM AUTHOR]