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Abstract

The functioning of European economies and societies requires a stable and sustainable supply of mineral resources. For 10 years now EU has been developing raw materials initiative to secure European minerals supply. In many cases, areas with known or hypothetic mineral resources, are not sufficiently valued by society and authorities, remain unprotected and face competing land uses with the risk of becoming sterilized. MINATURA 2020 project was born out of a need to develop a harmonised framework which allow a common way of identifying “mineral deposits of public importance” (MDoPI) and their safeguarding via land use planning. The project has left a useful set of guidelines and proposals how to advance on the creation of a European network of MDoPIs to avoid sterilization of “deposits worth safeguarding”. In Poland, the need for legal protection of mineral deposits has been discussed intensively in recent years. Various proposals aimed at better system of mineral deposits safeguarding, especially those which should be recognized as of public importance, have been proposed. However, until now only a few coal deposits were recognized as strategic. Currently, the Polish National Mineral Policy is under preparation. Its overriding objective is to provide access to the necessary minerals, also in the longterm perspective. It assumes among others activities aimed at protection of mineral deposits regarding land use planning system. Paper presents scope and general results of MINATURA2020 project, with details on MINATURA2020 methodology implementation in Poland, Project of the Polish National Mineral Policy with its objectives and key pillars, position of MDoPIs in this Project, and – finally – expected future steps related to MDoPI safeguarding in EU and in Poland.
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Abstract

In this paper, thermally-excited, lateral free vibration analysis of a small-sized Euler-Bernoulli beam is studied based on the nonlocal theory. Nonlocal effect is exerted into analysis utilizing differential constitutive model of Eringen. This model is suitable for design of sensors and actuators in dimensions of micron and submicron. Sudden temperature rise conducted through the thickness direction of the beam causes thermal stresses and makes thermo-mechanical properties to vary. This temperature field is supposed to be constant in the lateral direction. Temperatures of the top and bottom surfaces of the system are considered to be equal to each other. Governing equation of motion is derived using Hamilton’s principle. Numerical analysis of the system is performed by Galerkin’s approach. For verification of the present results, comparison between the obtained results and those of benchmark is reported. Numerical results demonstrate that dynamic behavior of small-sized system is been effected by temperature shift, nonlocal parameter, and slenderness ratio. As a result, taking the mentioned parameters into account leads to better and more reliable design in miniaturized-based industries.
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Abstract

In recent years, more and more attention has been paid to the quality of produced coal size categories for energy purposes. This is important from the perspective of promoting clean coal technologies which aim at changing the perception of coal as a fuel friendly for the environment. This is specifically because hard coal resources in Poland allow the national energy security to be guaranteed on the basis of energy production based on hard coal. Fine coals upgraded at coal processing facilities in the separation process in fine coal jigs are mainly used in energy production from coal. In the article, an analysis of hard coal upgrading in a jig regarding the optimum recovery of a useful fraction in the concentrate (combustible and volatile matter) and non-useful fraction in tailings (ash and sulfur) was conducted. Based on the industrial testing of a fine coal jig, the granulometric and densimetric analysis of the taken samples of concentrate, middlings and tailings of coal was conducted in laboratory conditions. Yields of products were calculated in separated size-fractions of separation products, and ash content and total sulfur content were determined in them. Based on the results of granulometric, densimetric and chemical analyses of the obtained size-fractions, the balance of separation products and appropriate calculations, Fuerstenau upgrading curves which allowed the process to be evaluated and a comparison of the results of hard coal upgrading regarding the optimum recovery of the organic phase in the concentrate and mineral components in tailings to be drawn. The obtained results were evaluated on the basis of different criteria for changing the device’s hydrodynamic operational conditions. The ash content and total sulfur content were analyzed as non-useful substances.
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