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1

Analysis of Gas and Dust Emissions From the Mining and Quarrying Sector in the European Union Countries

Tutak Magdalena

Multidisciplinary Aspects of Production Engineering

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2020

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Vol. 3, Iss. 1

71--82

EN

Despite the ongoing changes in the energy and economic structure of the European Union countries, mineral and energy resources such as hard coal, brown coal, natural gas, copper ores, zinc ores and many other minerals continue to be extracted. Each year, the mining and extraction sector emits thousands of tons of harmful substances into the atmosphere, in the form of greenhouse and other air-polluting gases, as well as harmful dusts. These substances include, amongst others, carbon dioxide, methane, carbon monoxide, as well as PM2.5 and PM10. The European Union climate policy clearly recommends that the exploitation of mineral resources be carried out in full respect of the principles of their rational, economical and environmentally neutral acquisition, which is confirmed by the promoted strategy of sustainable development economy. Therefore, this means the necessity to undertake actions aimed at limiting the emission of greenhouse gases and air pollutants into the atmosphere. To assess the actions taken by the European Union countries to date with respect to limiting those emissions, a comparative analysis was carried out for the particular countries. This analysis encompassed the emission of harmful substances from the mining and quarrying sector by the European Union countries in the years 2008 and 2017. The purpose of the analysis was to show the diversity of those countries in terms of the emission of harmful gases and dusts, as well as to divide them into similar groups. Such a division paves the way for developing a common climate policy and exchanging experiences between the countries from the particular groups. The European Union countries were divided into similar groups using the k-means grouping method. Comparison was also made for the emissions of the substances under analysis for the particular countries over the research years. The results obtained unequivocally demonstrate that this emission has been limited in the European Union, but there are countries where the emission of certain substances has increased.

2

Analysis of the similarity of hard coal mines in terms of the number of dangerous incidents caused by the activation of natural hazards

Tutak Magdalena

Multidisciplinary Aspects of Production Engineering

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2019

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Vol. 2, Iss. 1

91--100

EN

Hard coal mines and mining enterprises involved in hard coal exploitation in the area of the Upper Silesian Coal Basin (Górnośląskie Zagłębie Węglowe) are characterised by the presence of natural hazards typical of this type of exploitation. These hazards include the risks related to methane, coal dust explosion, endogenous fires, as well as rock burst and caving of roof rocks. The article presents the results of a taxonomic analysis aimed at determining the similarity of hard coal mines and mining enterprises in Poland in terms of the dangerous incidents caused by the risks related to methane, coal dust explosion, endogenous fires, as well as rock burst and caving of roof rocks. The analysis was carried out for the 2008-2018 data and encompassed a total of 26 hard coal mines and mining enterprises located in the Upper Silesian Coal Basin. The analysis was performed using the k-means method of non-hierarchical clustering. The main objective of the article was to determine homogenous groups (clusters) of mines exhibiting the greatest similarity in terms of dangerous incidents caused by the activation of natural hazards in the years 2008-2018. These data can be successfully used for the development of preventive measures and risk analyses for these enterprises.

3

Application of similarity method of distance courses describing the elements content in cement concrete after 50 forced thermal cycles

Linek Małgorzata

Journal of KONES

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2019

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Vol. 26, No. 4

155--162

EN

The article presents material solution based on the application of ceramic dust as concrete mix component intended for airfield pavements. The applied dust influences the changes in internal structure of concrete composite. Diversification of internal microstructure of cement concrete using the suggested dust has significant influence on the improvement of compressive strength. The laboratory analyses included concretes curing in standard conditions and concretes subject to thermal cycles representing the destructive influence of imposed loading. Comparative SEM observations of concretes subject to 50 thermal cycles proved significant influence of dust on internal structure of composite. In the study 6 samples were selected, which, each time, were intended for the laboratory tests. The applied similarity analysis of distance courses in case of this concrete. Similarity indexes between input and target sequence were defined. Diagrams presenting the similarity of the analysed concretes were prepared (after 28 days of curing and after 50 thermal cycles). It was proved that the suggested method can be used to assess the elements content and define the similarity of concrete intended for airfield pavements in the selected of areas (cement matrix, contact area between fine aggregate and cement matrix, contact area between coarse aggregate and cement matrix and contact area between air voids and cement matrix).

4

Application of similarity method of distance courses describing the elements content in typical cement concrete after thermal cycles

Linek Małgorzata, Nita Piotr

Journal of KONES

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2019

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Vol. 26, No. 4

163--170

EN

The work concerns the use of similarity analysis of distance course. Composition of concrete mixes was designed. The cement concrete composition includes cement, coarse aggregate, fine aggregate, water and admixtures. The laboratory analyses included concretes curing in standard conditions and concretes subject to thermal cycles representing the destructive influence of imposed loading. Laboratory tests assumed the fifty thermal test cycles. A single test cycle included process of alternate heating and cooling. Recurrent influence of temperature stimulated the impact of aircraft on airfield pavements. The assumed heating and cooling time corresponded to the time during which the aircraft effected the most frequently used airfield pavement within the area of Poland. Comparative SEM observations of concretes subject to thermal cycles were conducted. An increase in the width of microcracs has been observed. In case of crystallization, there is diversification within the area of cement matrix, contact area between cement matrix and aggregate grains and in case of porosity characteristics of both concretes. Similarity indexes between input and target sequence were defined. Diagrams presenting the similarity of the analysed concretes were prepared (after 28 days of curing and after thermal cycles). It was proved that the suggested method could be used to define the similarity of concrete intended for airfield pavements.

5

Application of similarity method of distance courses describing the elements content in typical cement concrete

Linek M.

Journal of KONES

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2018

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Vol. 25, No. 4

239--246

EN

The article concerns the use of similarity analysis of distance course in the internal area of cement concrete intended for airfield pavements. Research procedure was presented and the obtained laboratory tests results were discussed. The contents of diversified elements in four zones (cement matrix, contact area between air pores and cement matrix, contact area between fine aggregate and cement matrix and contact area between coarse aggregate and cement matrix) were specified by using scanning electron microscope. Based on the results obtained diagrams similarity of the analysed of areas in the concretes were prepared. The purpose of this article has been the assessment of an opportunity to apply the analysis of similarity of distance courses with respect to cement concrete intended for airfield pavements. The scope of article consisted of two stages. The analysis included cement concretes intended for airfield pavements, in compliance with requirements. The thermal analysis method was used; the selected concrete components were determined by means of quantitative method. The occurrence of crystalline stages was determined using X-ray diffraction method. Internal structure of concrete composite was assessed with the scanning electron microscope.

6

Application of similarity method of distance courses describing the elements content in cement concrete after frost resistance test

Linek M.

Journal of KONES

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2018

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Vol. 25, No. 3

331--337

EN

The work concerns test results of cement concrete and the use of similarity analysis of distance course. Research procedure was presented and the obtained laboratory tests results were discussed. Composition of concrete mixes was designed. The cement concrete composition includes cement, coarse aggregate, fine aggregate, water, admixtures and a ceramic addition. The addition of ceramic was used as a replacement for part of the fine aggregate Fresh concrete mixture parameters were tested and basic parameters of hardened concrete were defined (density, compression strength and tensile strength). The scope of works included concretes intended for airfield pavements and this concretes after frost resistance test. The test has been conducted in diversified media generally used in the course of winter maintenance. Subject to observations of internal structure of concretes and conducted chemical microanalyses using scanning electron microscope, the contents of diversified elements in four zones were specified. The following zones were subject to analysis: cement matrix, contact area between air pores and cement matrix, contact area between fine aggregate and cement matrix and contact area between coarse aggregate and cement matrix. Based on the results obtained diagrams similarity of the analysed concretes were prepared.

7

Application of similarity method of distance courses describing the elements content in concrete intended for airfield pavements

Linek M.

Journal of KONES

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2017

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Vol. 24, No. 4

385--392

EN

The work presents the applied similarity methods of distance courses in case of cement concrete intended for airfield pavements. Composition of concrete mixes was designed and their parameters were defined. Compressive strength of hardened concrete and components thereof and the occurrence of crystal phases were determined. Subject to observations of internal structure of concretes and conducted chemical microanalyses using scanning electron microscope, the contents of diversified elements in four zones were specified. Similarity indexes between input and target sequence were defined. Diagrams presenting the similarity of the analysed concretes were prepared. It was proved that the suggested method could be used to assess the elements content and define the similarity of concrete intended for airfield pavements. The scope of works consisted of two stages. During the first one, two series of cement concrete were prepared. The analysis included cement concretes intended for airfield pavements, in compliance with requirements. The influence of variable environmental conditions with respect to standard ones on the selected features of hardened concretes was assessed.

8

Application of similarity method of distance courses describing the elements content in pavement quality concrete

Linek M., Nita P.

Journal of KONES

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2017

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Vol. 24, No. 4

393--398

EN

The publication presents the application of similarity analysis of distance courses. This method has been applied to define similarity of cement concrete intended for airfield pavements. The scope of works included standard concretes intended for airfield pavements and concretes after frost resistance test. The test has been conducted in diversified media used in the course of winter maintenance. The nature of resistance of pavement quality concrete was discussed with respect to frost resistance thereof. Research procedure was presented and the obtained laboratory tests results were discussed. Concrete samples were subject to observations using scanning electron microscope in order to define changes occurring in the internal microstructure. Chemical microanalysis of concrete composition before, in the course of and after the frost resistance test and the occurring changes were specified. The obtained laboratory tests results were intended for the purposes of the similarity analysis. Results obtained in case of standard pavement quality concrete were considered as comparative values. Characteristics of the remaining concretes were referred to these values and then similarity of distance courses were analysed. It was proved that BWMt concrete was the most similar concrete to the comparative concrete.