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Abstract

The article describes the influence of anomalous values and local variability on the structure of variability and the estimation of deposit parameters. The research was carried out using statistical and geostatistical methods based on the Pb accumulation index in the shale series in part of the Cu-Ag ore deposit, LGCD (Lubin-Głogów Copper District). The authors recommend the use of a geostatistical tool, the so-called semivariogram cloud to determine the anomalous values. Anomalous values determined by the geostatistical method and removed from the dataset have resulted in a significant reduction of the relative variability of data, which is still very large in the case of the analyzed parameter or parameters with similar statistical features such as extreme variability and strongly asymmetric distribution. Calculations of the resources of this element can be treated only as estimates and formally classified to category D. The hypothetical assumption of the absence of sampling errors, resulting in a decrease in the magnitude of local variation, leads to a certain reduction of the median error of resource estimates. However, they are still high (> 35%). This is due to the large natural variability of the accumulation index of Pb on the local observation scale. The current method for collecting samples from mine workings of the Cu-Ag deposits in the Lubin-Głogów Copper District (LGCD), aimed at the proper assessment of copper resources, the Cu content, and at estimating the quality of copper output, makes it impossible to achieve an accuracy of estimates of Pb resources similar to that obtained for the main metal. Theoretically, this effect can be achieved by a strong concentration of the sample collection points and thanks to a multiple increase in the samples weight; this, however, is unrealistic for both economic and organizational reasons. It is therefore to be expected that the assessment of Pb resources and other accompanying elements of similar statistical features (e.g. As), located in parts of the deposit where mining activities are to be carried out, will be subject to significant errors.
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Abstract

Celem przeprowadzonego eksperymentu było zbadanie możliwości zastosowania upraw roślin energetycznych, w postaci mozgi trzcinowatej (Phalaris arundinacea), w procesie fitoremediacji terenów zanieczyszczonych herbicydami z grupy fenoksykwasów (2,4-D, MCPA) oraz wybranymi WWA (suma 10 WWA zgodnie z Dz.U. 2016, 1395). Dodatkowo, w ramach doświadczenia przeprowadzono ocenę kinetyki wzrostu i rozwoju proponowanego gatunku roślin w odniesieniu do nawożenia gleby kompostem pochodzenia odpadowego, nano ditlenkiem krzemu oraz mieszanką tych materiałów. Z akres wykonanych badań obejmował dwumiesięczny test donicowy w warunkach ex-situ z wykorzystaniem dwóch serii badawczych (seria 1 – kontrole bez roślin; seria 2 – próby z roślinami). Wyniki uzyskane w trakcie realizacji prac badawczych, pozwoliły wykazać, iż zastosowanie P. arundinacea, w charakterze „czynnika remediacyjnego”, pozwala na znaczące zwiększenie efektywności usunięcia zanieczyszczeń organicznych z gleby. Niemniej jednak zaznaczyć należy, iż najlepsze efekty zarówno w kontekście efektywności procesu, jak i ilości pozyskiwanej biomasy, uzyskane zostały pod wpływem aplikacji nawozu organicznego w postaci kompostu. Dodatkowo zaobserwowano, iż stosowanie materiałów o wysokich właściwościach sorpcyjnych, w charakterze substancji współnawożącej, może znacząco zwiększyć efektywność biotycznych procesów rozkładu zanieczyszczeń organicznych w glebie. Podsumowując można stwierdzić, że proponowana technologia fitoremediacji charakteryzuje się wysoką efektywnością działania, a jej praktyczna implementacja przyczynić się może dodatkowo do zwiększenia udziału produkcji energii z alternatywnych form paliw odnawialnych.
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Abstract

W pracy przedstawiono wybrane analizy oceny odporności dynamicznej zabudowy mieszkalnej i gospodarczej na wpływy eksploatacji górniczej w obszarze górniczym jednej z kopalń węgla kamiennego. Rozważania ograniczono do dynamicznych efektów związanych z powstawaniem wstrząsów górniczych generowanych podziemną eksploatacją surowca. W ramach pracy wykonano analizę sejsmiczności analizowanego obszaru z uwagi na wpływ rejestrowanych i prognozowanych drgań powierzchniowych na tradycyjną niską zabudowę murowaną. Wykonano modele symulacyjne zbudowane zgodnie z Metodą Elementów Skończonych oraz dobrano kryteria odporności dynamicznej. Kryteria odporności dynamicznej przyjęto zgodnie z obowiązującymi normami i zasadami projektowania budynków murowanych. Obliczenia przeprowadzono z wykorzystaniem metody spektrum odpowiedzi, która jest normową metodą projektowania obiektów poddanych wpływom wstrząsów górniczych. Takie podejście jest również zalecane przez większość polskich instrukcji i wytycznych dotyczących projektowania budynków w rejonach o sejsmiczności indukowanej działalnością wydobywczą. Efektem analiz było określenie wytężenia podstawowych elementów konstrukcyjnych w przyjętych modelach obliczeniowych. Wyniki analiz skoncentrowanych na wpływie wstrząsów górniczych na zabudowę powierzchniową i sieć infrastruktury technicznej oraz ich zabezpieczeniach w obszarze górniczym ZG Janina mogą być przydatne w kontekście możliwości dalszej eksploatacji pokładów węgla w kolejnych latach, z zachowaniem bezpieczeństwa powszechnego, ochrony obiektów budowlanych, w tym zapobiegania szkodom. Przedstawione w pracy wyniki stanowią również uzupełnienie tworzonej przez autorów od kilku lat bazy obiektów i modeli dynamicznych budowli poddanych wpływom wstrząsów górniczych.
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Abstract

Kolektory słoneczne są głównymi elementami solarnych systemów grzewczych. Praca tych urządzeń polega na konwersji energii promieniowania słonecznego na ciepło czynnika roboczego. Czynnikiem tym może być zarówno ciecz (glikol lub woda), jak i gaz (powietrze). Ze względu na konstrukcję wyróżnia się kolektory płaskie, próżniowe, próżniowo-rurowe i skupiające. Kolektory płaskie są stosowane przede wszystkim w budynkach, w których potrzeby cieplne są niskie lub średnie, czyli na przykład w gospodarstwach domowych. Rozwój kolektorów został ukierunkowany na zwiększenia wydajności oraz poprawy efektywności ekonomicznej inwestycji. W artykule oceniono wpływ zmiany powierzchni płaskich kolektorów słonecznych na opłacalność ekonomiczną inwestycji. Do analizy wytypowano dom jednorodzinny, zlokalizowany w województwie małopolskim, w którym instalacja przygotowania ciepłej wody użytkowej została rozbudowana o system solarny. System ten składa się z płaskich kolektorów, o łącznej powierzchni absorberów 5,61 m2. Jako czynnik roboczy w instalacji stosowany jest glikol. W celu poprawy efektu ekonomicznego zaproponowano zwiększenie powierzchni absorberów. Na podstawie trzyletnich pomiarów nasłonecznienia oraz efektów cieplnych instalacji, stworzono model ekonomiczny służący do oceny opłacalności zwiększenia powierzchni kolektorów słonecznych. Obliczenia z użyciem modelu promieniowania HDKR wykonano w środowisku Matlab dla lokalizacji Tarnów (najbliższej instalacji). Ponadto na podstawie rzeczywistych pomiarów z tej instalacji, odzwierciedlających wpływ wielu niemierzalnych czynników na efektywność przetwarzania energii słonecznej, wykonano symulacje efektu ekonomicznego dla różnych wielkości zapotrzebowania na ciepło. Otrzymane wyniki uogólniono, co daje możliwość ich wykorzystania w procesie doboru wielkości powierzchni kolektorów w przypadku podobnych instalacji.
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Abstract

Underground mining extraction causes the displacement and changes of stress fields in the surrounding rock mass. The determination of the changes is extremely important when the mining activity takes place in the proximity of post-flotation tailing ponds, which may affect the stability of the tailing dams. The deterministic modeling based on principles of continuum mechanics with the use of numerical methods, e.g. finite element method (FEM) should be used in all problems of predicting rock mass displacements and changes of stress field, particularly in cases of complex geology and complex mining methods. The accuracy of FEM solutions depends mainly on the quality of geomechanical parameters of the geological strata. The parameters, e.g. young modulus of elasticity, may require verification through a comparison with measured surface deformations using geodetic methods. This paper presents application of FEM in predicting effects of underground mining on the surface displacements in the area of the KGHM safety pillar of the tailing pond of the OUOW Żelazny Most. The area has been affected by room and pillar mining with roof bending in the years 2008-2016 and will be further exposed to room-and-pillar extraction with hydraulic filling in the years 2017–2019.
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Abstract

Prezentowany artykuł porównuje światowe rynki złota i ropy naftowej w celu wyjaśnienia zaskakująco wysokiej korelacji cen obu surowców od roku 1970 oraz imponującego ich wzrostu w porównaniu z cenami praktycznie wszystkich pozostałych surowców. Autorzy sugerują, że rozwój sytuacji na rynku naftowym i wynikające z niego skutki makroekonomiczne wpłynęły na inwestycje w złoto, zapewniając w ten sposób najbardziej wiarygodne wyjaśnienie dla synchronizacji zmian cen obu towarów. Analizując nadzwyczajne wzrosty cen ropy naftowej i złota, w szczególności w porównaniu z cenami innych metali i innych surowców mineralnych, autorzy zakładają, że najpierw nastąpił wzrost cen ropy, wywołany przez zewnętrzne ograniczenia dotyczące zdolności produkcyjnych. W konsekwencji wzrosła cena złota, niejako odpowiadając na potrzebę bezpiecznych inwestycji dla zachowania wartości środków inwestycyjnych, co jest cechą charakterystyczną złota, której nie posiadają inne metale i surowce mineralne. Prezentowany artykuł omawia także prawdopodobną ewolucję cen tych ważnych surowców argumentując, że ceny ropy w najbliższych dziesięcioleciach utrzymają swój poziom lub obniżą się, a ceny złota będą nadal kontynuowały wzrost, co doprowadzi do zniesienia związku pomiędzy cenami ropy i złota.
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Abstract

W artykule zbadano możliwość wykorzystania popiołów lotnych klasy C (otrzymywanych w wyniku spalania węgla brunatnego w kotle pyłowym) i F (otrzymywanych w wyniku spalania węgla kamiennego metodą konwencjonalną) jako substratów do syntezy materiału zeolitowego z grupy filipsytu. W tym celu przeprowadzono szereg syntez hydrotermalnych z wykorzystaniem reagentów takich jak wodorotlenek sodu (NaOH) oraz bromek tetrapropyloamoniowy (TPABr). W wyniku reakcji otrzymano docelowy materiał zeolitowy, zarówno z popiołu klasy C, jak i F. Otrzymane produkty syntezy, jak też popiołowe substraty reakcji, poddano charakterystyce chemicznej i mineralogicznej. Badania wykazały, że popiół lotny powstały z węgla brunatnego i kamiennego może być substratem w reakcjach syntez zeolitu, jakim jest filipsyt. Analiza porównawcza dyfraktogramów rentgenowskich produktów z obu typów popiołów wykazała, że lepszym substratem jest popiół klasy C otrzymywany w wyniku spalania węgla brunatnego w kotle pyłowym (w reakcji syntezy otrzymano lepiej wykształcone formy zeolitowe). W pracy dokonano także analizy literaturowej potencjalnych kierunków zastosowania filipsytu w inżynierii i ochronie środowiska. Na podstawie zweryfikowanych danych stwierdzono, iż dalszym kierunkiem badań będzie analiza możliwości wykorzystania otrzymanych materiałów jako potencjalnych sorbentów amoniaku.
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Abstract

Coal mining activities carried out for 200 years in Upper Silesia have had a negative effect on buildings. T his impact is in all cases related with continuous deformations of the surface and in certain cases with discontinuous deformations (mostly cave-ins), changes in water relations and mining tremors. T he paper presents an evaluation of the impact of a mining activity on a building situated in the Upper Silesian Coal Basin. T he building was affected by continuous deformations and mining tremors. Calculations were made of the values of deformation rates by means of Budryk–Knothe’s theory, which were partly verified on the basis of the results from geodetic measurements. An analysis of the velocity and acceleration of basement vibrations caused by mining-induced tremors was also conducted. T he conclusions included a high consistency between the results obtained on the basis of calculations and the values obtained by means of PGA and PGV measurements. In the case of tremors with the highest energy in the hipocentrum, there an empirical formula allowing for calculation of PGA value in given geological and mining conditions was also proposed. T he application range of the formula mentioned above is obviously limited only to the conditions in consideration. The presented conclusions indicate that at present, sufficiently precise methods, allowing for calculations for practical purposes, not only of deformation indices’ values, but also of PGV and PGA values, presently exist.
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Abstract

The presented article describes the relationship between lithological and facies development of reservoir rocks in the area of the roof elevation of the Weissliegend sandstones, with a particular emphasis on the influence of elevation on the occurrence of low mineralization zones in the deposit area. To illustrate the variability of the deposit parameters, closely related to the facies and lithological conditions of the host rocks, three-dimensional lithological and geochemical models for two research areas were developed using the geostatistical methods and based on field observations and the sampling of the deposit. The research area includes parts of the Northern Elevation of Rudna and the surrounding depressions within the boundaries of the Sieroszowice and Rudna deposits. Based on cross-sections of the 3D models, a different deposit formation in the roof elevation area of sandstone formations has been characterized; the lithological profile is defined as „atypical” due to the absence of a copper-bearing shale series, the most characteristic layer for copper ore deposits in the Fore -Sudetic monocline. Large variations in the shape of the deposit and the irregular boundaries of both balance mineralization and enclaves of gangue have been confirmed. The presence of large-scale enclaves of igneous rock in the entire profile of the Lower Zechstein rocks (areas without the balance copper mineralization) and small areas of gangue (sandstone) enriched with anhydrite binders adjacent to the parts of balance deposit located in argillaceous sandstone has been revealed. The possibility of the occurrence of gangue, in the area of the roof elevation of the Weissliegend sandstones directly adjacent to the border with calcareous dolomite, and irregular gangue partings in sandstone formations in the balance deposit was indicated. In addition, small areas of strong enrichment in Cu sulphides were observed in the contact zones between sulphate and clay binders in the Weissliegend sandstone series.
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Abstract

Coal reserves in the Czech Republic are estimated to be 10 billion tons – hard coal about 37%, brown coal about 60% and lignite 3%. Hard coal is produced in Northern Moravia. In 2017 the production of hard coal was 5.5 million tons. Brown coal is mined in North-Western Bohemia − the production of brown coal in 2017 was 38.1 million tons. Significant quantities of hard coal are exported to: Slovakia, Austria, Germany and Hungary. In accordance with the National Energy Policy, coal will remain the main source of energy in the country in the future, despite the increased use of nuclear energy and natural gas. The government expects that in 2030 energy from coal will account for 30.5% of energy produced. There are five coal companies in the Czech Republic: OKD, a.s., the only hard coal producer and four brown coal mining companies: Severočeské Doly a.s., owned by ČEZ, the largest producer of brown coal, Vršanská uhelná a.s., with coal resources until 2055, Severní energetická a.s. with the largest brown coal reserves in the Czech Republic and Sokolovska uhelná a.s., the smallest mining company extracting lignite. OKD operates coal in two mines Kopalnia Důlní závod 1 – (consists of three mines: ČSA Mine, Lazy Mine, Darkov Mine) and Mine Důlní závod 2 (ttwo mines Sever, Jih). The article also presents a pro-ecological solution for the management of waste heaps after coal enrichment – a plant for the enrichment of coal waste from the Hermanice heap.
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Abstract

Wood pellets are classified as a solid biomass type. They are one of the most popular bio-heating fuels used in Europe, especially in the small heating sector, where pellets are burned in low-power domestic boilers. The pellets and automatic pellet-fired heating devices gained popularity due to the increasing air pollution (smog) problem and the low emission limiting campaigns associated with it. Wood pellets are formed as a result of small forestry particles mechanical compression (mainly conifers originated) and they are listed among renewable energy sources. The purpose of the presented studies was to compare the quality of wood pellets used for pellet-fired boilers and to identify, qualitatively and quantitatively, impurities marked in the samples obtained from the domestic market. The application of petrographic analyses, applied so far in relation to fossil fuels, is a presented work innovation for wood pellets. The microscopic analyses were performed on both certified (ENplus/DINplus) and uncertified wood pellets available on the market. Unfortunately, the analysis revealed that the quality requirements were not met, because of the unacceptable contamination presence. The unacceptable organic inclusions in the analyzed samples are fossil coals and their derivatives, coke, and polymeric materials of natural origin. Unacceptable inorganic inclusions determined in the analyzed samples were: glass, slag, rust, pieces of metal, stone powder, plastic, and polymeric materials of inorganic origin.
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Abstract

Petrographic and physico-chemical analyses of ashes are carried out on a large scale and presented in numerous scientific papers. The mentioned ashes are obtained from filters and electrostatic precipitators mounted in large industrial installations. The large-scale analysis of the ashes obtained directly from grate furnaces or blast furnaces mounted in low-power boilers started with combating smog and low-stack emissions. The collection of ash samples from household furnaces usually involves the analysis of the combustion of waste in low-power boilers. This is justified in the case of old type boilers, which were designed to use virtually any fuel. Currently, new types of boilers, designed to burn dedicated fuels, are offered on the market. The aim is to use only renewable fuels (biomass) or fossil fuels with high quality parameters, which are more environment-friendly, e.g. eco-pea coal, lignite briquettes, or peat briquettes. The authors of the study focused on examining the ash obtained from boilers for burning wood pellets by performing microscopic analysis of residues after biomass combustion. The above mentioned analysis provides a comprehensive information on the efficiency of the combustion process, the content of contaminants remaining in the ash, and the suitability of ash for other applications. The entire process, from the moment of collecting the samples to the execution of the analysis takes up to 12 hours, which ensures a quick decision on furnace adjustment or fuel change. The ash components were determined based on the results obtained by the Fly-Ash Working Group of the International Committee for Coal and Organic Petrology (ICCP). The mentioned classification has been supplemented with new key elements occurring in ashes resulting from the combustion of wood pellets in household boilers. This allowed determining the percentage content of characteristic components in the tested material, which can be used as a specific benchmark when issuing opinions on the quality and efficiency of the boiler and the combusted pellets.
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Abstract

The environment is the greatest good for the people. Everyone wants to breath air of the best possible quality, whether living in the city center of a metropolis or in a rural area. Air polluted with very fine particles contribute to the negative effect on people’s health and the whole environment. A significant part of air dust pollution comes from the so-called low emissions sources which include: non-standard furnaces, fireplaces, low-efficiency outdated boilers and local heat sources. Since the beginning of Polish Mining Group’s existence, the company actively participates and supports many activities, the aim of which is to improve the air quality by producing and supplying high quality coal for the residential sector. The company has undertaken pro-ecological activities towards creating a new, pro-ecological strategy as well as product offer. The production of an ecological coal assortment is systematically developing but new coal products are also being launched on the market. One of the company’s priorities is the production of thermal coal for the residential sector. Many organizational and technological changes have been made In that area (e.g. the establishmsnt of the Eco-Fuels Production Plant) to ensure a suitable level of production of the highest quality thermal coal.
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Abstract

Poland is now faced with the task of developing a long-term energy policy for decades to come, a strategy capable of reconciling the security of power supplies as well as effective economic processes, ensuring adequate standards of environmental protection. The process in which fossil fuels are converted into energy carriers of choice is accompanied by the emission of various gas substances which escape into the environment. Later on, those substances accumulate in the atmosphere as greenhouse gases affecting the Earth’s radiation balance – the greenhouse effect. Upsetting the balance between emission levels of those gases and the capacity to convert them in the atmosphere is the reason for climate changes. Sustainable development indices constitute a monitoring tool which makes it possible to create a statistical image of a country from the perspective of a new development paradigm. The most important feature of this index is the capability of comparing values, enabling to determine the position of a given object with reference to other objects. The article analyses 8 indexes of sustainable development in terms of using biomass for power generation purposes. The analysis was performed to include three social order indices, two economic indices and one environmental order index. It was concluded that the use of biomass in power generation can reduce the emission of greenhouse gasses significantly at several stages: the emission can be eliminated from the biological process of biomass conversion, storage and it can also be reduced during transportation.
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Abstract

The paper presents selected issues related to the development of international coal markets. World consumption of coal dropped for the second year in a row in 2016, primarily due to the lower demand from China and the US. The share of coal in global primary energy consumption decreased to 28%. World coal production accounted to 3.66 billion toe and it was lower by 6.2% when compared to the previous year. More than 60% of this decline took place in China. The decline in global production was more than four times higher than the decrease in consumption. The sufficiency of the world resources of coal are estimated at 153 years – that is three times more than the sufficiency of oil and gas resources. After several years of decline, coal prices increased by 77% in 2016. The current spot prices are at the level of $80/ton and are close to the 2014 prices. In the European market, after the first half of the year, coal prices reached the level of around 66% higher than in the same period of the last year. The average price in the first half amounted to PLN 12.6/GJ, which is close to the 2012 prices. The share of spot trade in the total purchase amount accounted to approx. 20%. Prices in futures contracts can be estimated on the basis of the Japan-Australia contracts prices and prices in supplies to power plants located in Germany. On average, the prices in supplies to these power plants were higher by approximately 9% in the years 2010 – 2016 and prices in Australia – Japan contracts were 12% higher than CIF ARA prices in 2017. Global energy coal trade reached about 1.012 billion tons in 2016. A decline by 4.8% is expected in 2019 primarily due to the expected reduction in demand in major importing countries in Asia.
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Abstract

W artykule przybliżono charakterystykę frakcji nadsitowej wytwarzanych w regionalnych instalacjach przetwarzania odpadów komunalnych. W lipcu 2013 roku wprowadzono zmiany do ustawy o czystości i porządku w gminie, które wdrożyły w Polsce nowy model gospodarki odpadami komunalnymi oparty na mechaniczno-biologicznym ich przetwarzaniu. Podstawowym elementem tego systemu są sortownie odpadów komunalnych, które są obecnie źródłem wytwarzania frakcji nadsitowej posiadającej własności paliwowe. Dla potrzeb rozpoznania jej właściwości autorzy artykułu przeprowadzili badania własne koncentrujące się na rozpoznaniu podstawowych własności energetycznych frakcji nadsitowej w poszczególnych sezonach roku wraz z rozróżnieniem rodzajów zabudowy. Przeprowadzono badania składu morfologicznego dla potrzeb określenia koncentracji frakcji energetycznych. Przeanalizowano stabilność jakościową strumienia frakcji nadsitowej pod względem możliwości energetycznego zagospodarowania w instalacjach termicznego przekształcania odpadów. Badania składu morfologicznego wykazały podwyższoną koncentrację frakcji energetycznych (papier, tworzywa sztuczne, tekstylia) w stosunku do zmieszanych odpadów komunalnych. Jednocześnie badania własności energetycznych wskazują na podwyższoną standaryzację energetyczną tej frakcji w rozkładzie czasowym (pory roku) oraz rozkładzie przestrzennym (zróżnicowany rodzaj zabudowy). Badania wykazały, że wartość opałowa w zbadanych próbkach zawiera się w przedziale 18,1–23,5 MJ/kg, gdzie wartość średnia wynosi 21,5 MJ/kg. Udział popiołu zawiera się natomiast w przedziale 11,8–24,1%, a udział części palnych 67,6–77,5%. Dobre własności paliwowe oraz standaryzacja jakościowa strumienia wskazują na możliwość stosowania rozwojowych technologii zgazowania odpadów zgodnie z nowymi przepisami dyrektywy IED (Dyrektywa 2010). Technologia zgazowania, produkcja syngazu i jego spalanie w silnikach tłokowych małej mocy stanowią obecnie interesującą alternatywę dla klasycznych instalacji termicznego przekształcania odpadów opartych na technologii spalania wpisując się w rozwój instalacji RIPOK i potrzebę wdrażania gospodarki w obiegu zamkniętym.
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Abstract

Coal in Poland is an available conventional fuel providing energy security and independence of the country. Therefore, conventional energy generation should be based on coal with the optimal development of renewable energy sources. Such a solution secures the energy supply based on coal and the independence of political and economic turmoil of global markets. Polish coal reserves can secure the energy supply for decades. Coal will surely be important for energy security in the future despite the growing share of oil and gas in energy mix. The development of renewable power generation will be possible with the conventional energy generation offsetting volatile renewable power generation as Poland’s climate doesn’t allow for the stable and effective use of renewable energy sources. Considering the policy of the European Union with respect to emission reductions of greenhouse gasses and general trends as reflected in the Paris agreement in 2016, as a country we will be forced to increase renewable energy production in our energy mix. However, this process cannot impact the energy security of the country and stability and the uninterrupted supply of energy to consumers. Therefore seeking the compromise with the current energy mix in Poland is the best way to its gradual change with the simultaneous conservation of each of the sources of energy. It’s obvious that Poland can not be lonely energy island in Europe and in the world, which increasingly develops distributed energy and/ renewable technologies as well as energy storage ones. One can notice that without renewable generation and the reduction of coal’s share in country’s energy mix we will become the importer of electricity with raising energy dependence.
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Abstract

The purpose of the article was to characterize the international steam coal market based on the latest available data. The information goes back to the first half of 2018. The article focuses on the description of the three largest exporters and importers of steam coal. Representatives in these categories were selected using the latest global statistics on 2017. In 2017, global production of steam coal amounted to 5.68 billion tons and exceeded production in 2016 by 4%. For several years, invariably the world’s leading exporters of steam coal are: Indonesia, Australia and Russia. In total, these three countries in 2017 supplied 73% of steam coal to the international market. However, for the 46% of global steam coal imports (data for 2017), three Asian countries are responsible: China, India and Japan. For each of the six listed countries (i.e. for: three major global exporters and three major global importers), the paper presents volumes related to coal production, export or import. The directions of deliveries or major coal exporters to a given country were also included. At the end of the article, the price situation was presented, as it appeared in the first half of 2018 on the European and Asian markets.
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The paper presents an analysis of the influence of the energy generated from renewable sources on an improvement in the energy efficiency of public utility building and households. It also presents the current state of the technologies for the production of electricity from renewable sources, as well as their share in the national power supply system. The conducted analysis concerns both micro, as well as large systems generating electricity. Systems generating power from renewable sources are gaining in popularity. With an increasing awareness in the society of the beneficial influence that renewable power generating systems have on the environment, as well as the support in form of various programs offering subsidies for the construction of new systems, power generation from renewable sources is becoming increasingly popular and common. Although the renewable energy systems are still not widely considered to be a profitable solution, systems using renewable sources of energy are positively perceived and treated as a new trend in the construction of multi or single-family residential buildings. The increasing share of the renewable energy in the national power supply system significantly reduces the demand for energy produced from conventional sources. This obviously translates into a reduced consumption of primary energy, for example, fossil fuels, and, in turn, leads to the reduced exploitation of natural resources, thus contributing to the protection of the natural environment. A reduced consumption of fossil fuels also means a significant reduction in environmental pollution during their processing into electricity or heat. Actions aiming at improving energy efficiency and reducing final energy consumption are being undertaken by many countries all over the world, and by the European Union. In 2012, the European Parliament and the Council issued Directive 2012/27/EU obliging the Member States to initiate actions aiming at a reduction in the consumption of final energy by 1.5% a year. The paper presents the current status of generation of energy from renewable sources during the last 13 years. The ways for using energy from the renewable sources to improve the energy efficiency of facilities were also discussed.
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The issue of mercury emission and the need to take action in this direction was noticed in 2013 via the Minamata Convention. Therefore, more and more often, work and new law regulations are commencing to reduce this chemical compound from the environment. The paper presents the problem of removing mercury from waste gases due to new BREF/BAT restrictions, in which the problem of the need to look for new, more efficient solutions to remove this pollution was also indicated. Attention is paid to the problem of the occurrence of mercury in the exhaust gases in the elemental form and the need to carry out laboratory tests. A prototype installation for the sorption of elemental mercury in a pure gas stream on solid sorbents is presented. The installation was built as part of the LIDER project, financed by the National Center for Research and Development in a project entitled: “The Application of Waste Materials From the Energy Sector to Capture Mercury Gaseous Forms from Flue Gas”. The installation is used for tests in laboratory conditions in which the carrier gas of elemental mercury is argon. The first tests on the zeolite sorbent were made on the described apparatus. The tested material was synthetic zeolite X obtained as a result of a two-stage reaction of synthesis of fly ash type C with sodium hydroxide. Due to an increase, the chemical affinity of the tested material in relation to mercury, the obtained zeolite material was activated with silver ions (Ag+) by an ion exchange using silver nitrate (AgNO3). The first test was specified for a period of time of about 240 minutes. During this time, the breakthrough of the tested zeolite material was not recorded, and therefore it can be concluded that the tested material may be promising in the development of new solutions for capturing mercury in the energy sector. The results presented in this paper may be of interest to the energy sector due to the solution of several environmental aspects. The first of them is mercury sorption tests for the development of new exhaust gases treatment technologies. On the other hand, the second aspect raises the possibility of presenting a new direction for the management and utilization of combustion by-products such as fly ash.
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Abstract

Coal combustion processes are the main source of mercury emission to the environment in Poland. Mercury is emitted by both power and heating plants using hard and brown coals as well as in households. With an annual mercury emission in Poland at the level of 10 Mg, the households emit 0.6 Mg. In the paper, studies on the mercury release in the coal and biomass combustion process in household boilers were conducted. The mercury release factors were determined for that purpose. For the analyzed samples the mercury release factors ranged from 98.3 to 99.1% for hard coal and from 99.5% to 99.9% for biomass, respectively. Due to the high values of the determined factors, the amount of mercury released into the environment mainly depends on the mercury content in the combusted fuel. In light of the obtained results, the mercury content in the examined hard coals was 6 times higher than in the biomass (dry basis). Taking the calorific value of fuels into account, the difference in mercury content between coal and biomass decreased, but its content in coal was still 4 times higher. The mercury content determined in that way ranged from 0.7 to 1.7 μg/MJ for hard coal and from 0.1 to 0.5 μg/MJ for biomass, respectively. The main opportunity to decrease the mercury emissions from households is offered by the use of fuels with a mercury content that is as low as possible, as well as by a reduction of fuel consumption. The latter could be obtained by the use of modern boilers as well as by the thermo-modernization of buildings. It is also possible to partially reduce mercury emissions by using dust removal devices.
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The article presents the directions of foundry waste management, mainly used for spent foundry sands (SFS) and dust after the reclamation of this waste. An important aspect of environmental protection in foundry production is the reduction of the amount of generated waste as a result of SFS regeneration. The advantage is the reuse of waste, which reduces the costs of raw materials purchase and environmental fees for landfilling. Non -recycled spent foundry sands can be used in other industries. SFS is most often used in road and construction industries as well as inert material in closed mines (Smoluchowska and Zgut 2005; Bany-Kowalska 2006). An interesting direction of using SFS is its application in gardening and agriculture. The article presents the advantages and disadvantages of such use. It was found that spent foundry sands can be useful for the production of soil mixtures for many agricultural and horticultural applications. Due to the possibility of environmental pollution with heavy metals and organic compounds, such an application is recommended for the so-called green sands, i.e. SFS with mineral binders. In addition, an innovative solution for the energy use of dusts after spent foundry sands reclamation with organic binders has been discussed and proposed by some researchers. It was shown that dust from reclaimed SFS with organic binders can be used as an alternative fuel and raw material in cement kilns, due to the high percentage of organic substances which determine their calorific value and silica.
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Abstract

According to International Energy Agency (IEA) energy security is the continuous supply of energy at acceptable prices. National energy is based primarily on its own energy resources such as hard coal and brown coal. The 88% of electric energy production from these minerals gives us full energy independence. Additionally, the energy production costs from these raw materials are the lowest compared to other technologies. Of these two, the energy produced from brown coal is characterized by the lowest unit technical generating cost. Poland has the resources of these minerals for decades to come, the experience related to mining and processing them, scientific and design facilities and technical facilities and factories producing machines and equipment for their own needs, as well as for export. Coal is and should remain an important source of electricity and heat supply in Poland for the next 25–50 years. It is one of the most reliable and profitable energy sources. This policy may be difficult in the next decades due to the exhaustion of the available resources of hard and brown coal. The conditions for the construction of new mines, and thus for the development of coal mining in Poland, are very interdisciplinary in legal, environmental, economic and reputational terms. Germany has similar problems. Despite the fact that it is an image of a country investing in renewable energy sources, which are pioneers of energy production from RES, in reality hard and brown coal are still the primary sources utilized to produce electric energy.
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Abstract

For a very long period of time, Polish waste management was based mainly on landfilling at landfills, which had a negative impact on the surrounding environment. The EU requirements for the Member States have led to a revolution in Polish legislation on waste management and local governments have become responsible for creating local waste management systems that will affect the achievement of EU targets. One of the solutions undertaken by several municipalities is the construction and operation of a municipal waste thermal treatment installation, which not only reduced the amount of waste deposited, but also supported the local power industry by generating electricity and heat. The emission standards for installations producing energy from waste, as in the case of conventional power plants and combined heat and power plants, are very strict, therefore, the continuous monitoring of emitted pollutants is carried out, and waste gas treatment systems are developed based on the best available techniques (BAT). The article presents emission standards applicable to waste incineration plants, including duties in the field of the environment, as well as issues related to the installation as a source of energy. In addition, the currently functioning waste incineration plants in Poland have been briefly characterized, and development plans in this area in the country have been described.
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Abstract

The coal fed to gravity enrichment consists of coals coming from different deposits and exploitation fronts. These coals differ in quality parameters, especially the amount of gangue (stone) changing over time. This results in the instability of work, especially jiggers, which have a relatively low accuracy assessed by probable scattering or imperfection rates. This deteriorates the quality of the concentrate obtained, the quality parameters of which change over time. The improvement of jiggers work would be possible by averaging the feed. This process is practically impossible due to the failure to design such a node during plant construction, which are, in most cases, directly related to the shaft. In the article, the authors propose to solve the process of averaging the feed before directing it to the enrichment process in jiggers by introducing its deshaling in vibratory- air separators of the FGX type.
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