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Słowa kluczowe natural gas LNG energy balance

Abstrakt

In recent years, changes have been made in the structure of primary energy use in the European Union In addition, a reduction in the use of primary energy has also been observed. According to the forecasts of the International Energy Agency, the European energy market will be subject to further changes in the perspective of 2040. These may include the reduction of the energy consumption and the change in the structure of the energy balance as a result pro-ecological activities. Natural gas will be the only fossil energy carrier whose role in covering the energy demand will not change. Along with the changes taking place in the European energy market, global changes can also be observed. The EU Member States will continue to strive to diversify natural gas supplies. One of the main elements of diversification of natural gas supplies is the use of LNG regasification terminals. The reasons for that include the increasing production of natural gas, particularly in the case of unconventional deposits, the ongoing development of liquefaction terminals, and, as a consequence, an increase in the LNG supply in the global market. The article presents the utilization of regasification terminals in the EU Member States and plans for the development of LNG terminals. Europe has the opportunity to import natural gas through LNG terminals. However, until now, these have been used to a limited extent. This may indicate that in addition to diversification tasks, terminals can act as a safeguard against interruptions in gas supplies.
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Energy from different sources is fundamental to the economy of each country. Bearing in mind the limited reserves of non-renewable energy sources and the fact that their production from new deposits is becoming less economically viable, attention is paid to alternative energy sources, particularly those that are readily available or require no substantial financial investment. One possible solution may be to generate hydrogen, which will then be used for heat (energy) production using other methods. At the same time, these processes will be characterized by low emission levels compared to conventional energy sources. In recent years, more and more emphasis has been placed on the use of clean energy from renewable sources. New, more technically and economically efficient technologies are being developed. The energy use worldwide comes mostly from fossil fuel processing. It can be observed that the share of RES in global production is growing every year. At the end of the 1990s, the share of renewable energy sources was at 6–7%. Global trends indicate the increasing demand for renewable energy due to its form. Global hydrogen resources are practically inexhaustible, but the problem is its availability in molecular form. The article analyzed the use of hydrogen as a fuel. The basic problem is the inexpensive and easy extraction of hydrogen from its compounds; attention has been paid to water, which can easily be electrolytically decomposed to produce oxygen and hydrogen. Hydrogen generated by electrolysis can be stored, but due to its physicochemical properties, it is a costly process; therefore, a decision was made that it is better to store it with natural gas or use it for further reaction. In addition, hydrogen can be used as a substrate for binding and converting the increasingly problematic carbon dioxide, thus reducing its content in the atmosphere.
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Abstrakt

Na przestrzeni ostatniej dekady zauważalne są zmiany w strukturze zużycia energii pierwotnej w krajach UE. Jedną z najistotniejszych zmian jest rosnący udział przypadający na odnawialne źródła energii (OZE). Wzrost udziału OZE wynika między innymi z prowadzonej polityki mającej na celu zmniejszenie emisji gazów cieplarnianych. W osiągnieciu zamierzonych celów wykorzystywane są te nośniki energii, których wpływ na środowisko przyrodnicze jest jak najmniejszy, do takich paliw zaliczany jest gaz ziemny. Udział tego paliwa w bilansie energetycznym UE w analizowanym okresie, tj. od 2006 do 2016 r., utrzymuje się na względnie stałym poziomie. Natomiast w przypadku poszczególnych państw jego udział w bilansie energetycznym jest uzależniony od specyfiki danego państwa. Bez względu na udział gazu ziemnego w strukturze zużycia energii poszczególnych państw, dążą one do dywersyfikacji dostaw gazu ziemnego. Jednym z głównych elementów dywersyfikacji dostaw gazu ziemnego jest budowa terminali regazyfikacyjnych LNG. Z uwagi na fakt, że wzrasta ilość państw, które zainteresowane są eksportem gazu ziemnego w formie LNG, wzrasta także zainteresowanie odbiorem tego gazu przez państwa uzależnione od jego importu. W artykule przedstawiono stopień wykorzystania terminali regazyfikacyjnych LNG w Europie w okresie od 2012 do stycznia 2018 roku. Scharakteryzowano również terminal LNG w Świnoujściu, stopień jego wykorzystania oraz plany rozbudowy. Europa posiada znaczne możliwości importu gazu ziemnego poprzez terminale LNG, jednak do tej pory wykorzystywane one były w ograniczonym zakresie, świadczyć to może o tym, że oprócz zadań dywersyfikacyjnych terminale stanowią zabezpieczenie na wypadek przerw w dostawach gazu przy użyciu gazociągów.
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Abstrakt

W ostatnich latach światowy rynek gazu ziemnego uległ bardzo znaczącym zmianom. Dotychczas stosowane podejście w relacjach handlowych dostawca–odbiorca gazu ziemnego determinowane było sposobem dostawy tego surowca – tj. głównie za pomocą gazociągów. Powodowało to istotne napięcia polityczno-gospodarcze pomiędzy zainteresowanymi stronami. Należy także mieć na uwadze, że dostawy gazu w formie LNG mogą umocnić swoją pozycję w strukturze bilansu energetycznego Unii Europejskiej ze względu na obserwowane zmniejszające się wydobycie gazu na terenie państw należących do UE. Pomimo spadku konsumpcji gazu ziemnego w UE w ostatnich latach jego rola może wzrosnąć m.in. z powodu realizowanej polityki klimatycznej. Jednym z głównym czynników wpływających na zmiany na światowym rynku gazu jest tzw. rewolucja łupkowa jaka miała miejsce w Stanach Zjednoczonych oraz plany tego kraju, aby stać się istotnym graczem na światowym rynku gazu, dzięki wykorzystaniu technologii LNG. Do roku 2013 USA intensywnie rozbudowywały swoje zdolności importowe LNG, które stanowiły ponad 19% światowych zdolności regazyfikacyjnych. Mając na uwadze wzrost udokumentowanych zasobów gazu ziemnego w USA, zrezygnowano z realizacji kolejnych projektów terminali importowych, a w ich miejsce powstają terminale skraplające, dzięki którym USA będą eksporterem LNG, co znacząco może zmienić światowy rynek gazu ziemnego. Zgodnie z przewidywaniami do 2022 roku zdolności eksportowe LNG wzrosną o 460 mld m3/rok, z czego 82 mld m3/rok przypadać będzie na USA. W artykule przedstawiono możliwy wpływ rewolucji łupkowej w USA na rynek gazu ziemnego w Europie. Przedstawiono uwarunkowania ekonomiczne eksportu LNG w USA. Należy jednak mieć na uwadze, że jednym z najważniejszych czynników decydujących o przekierowaniu LNG do Europy będą miały ceny na azjatyckim rynku gazu ziemnego, gdzie dostawy LNG odgrywają istotną rolę w zbilansowaniu zapotrzebowania na gaz.
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The main goal of the considered work is to adjust mathematical modeling for mass transfer, to specific conditions resulting from presence of chemical surface reactions in the flow of the mixture consisting of helium and methanol. The thermocatalytic devices used for decomposition of organic compounds incorporate microchannels coupled at the ends and heated to 500 ◦C at the walls regions. The experiment data were compared with computational fluid dynamics results to calibrate the constants of the model’s user defined functions. These extensions allow to transform the calculations mechanisms and algorithms of commercial codes adapting them for the microflows cases and increased chemical reactions rate on the interphase between fluid and solid, specific for catalytic reactions. Results obtained on the way of numerical calculations have been calibrated and compared with the experimental data to receive satisfactory compliance. The model has been verified and the performance of the thermocatalytic reactor with microchannels under hydrogen production regime has been investigated.
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The phytotoxic effects of fluoride and its derivatives on the seeds and seedlings of the Colobanthus apetalus and Colobanthus quitensis were studied. This is a first study to evaluate the influence of sodium fluoride (NaF) on the morphophysiological and biochemical processes on two Colobanthus species. The influence of various concentrations of NaF (9 mM, 19 mM, 29 mM) on the germination capacity and germination rate of seeds, seedlings growth and the proline content of plant tissues was analyzed under laboratory conditions (20/10°C, 12/12 h). The seeds of C. apetalus were collected from a greenhouse, whereas the seeds of C. quitensis were collected in Antarctica and in a greenhouse (Olsztyn, Poland). The tested concentrations of NaF did not suppress the germination of C. apetalus seeds, but the germination of C. quitensis seeds was inhibited. Sodium fluoride mainly inhibited root growth of C. apetalus and C. quitensis. In both analyzed species, the free proline content of seedlings increased significantly under exposure to NaF. The results of this study clearly indicate that C. apetalus and C. quitensis are highly resistant to NaF stress.
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Paper deals with the new localizer GLOP2 designed for detection of the miners trapped in underground hard coal mines. The results of a field test conducted in coal mine BOBREK show that the presented localizer allows for efficient measurement of the distance between a trapped miner and the rescuer in the range of up to 15 m.
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Within this article a large scope of issues associated with development conditions and specifics of shaping the new image of Gdańsk waterfront was presented. The special attention was paid to its part situated within its central zone, located within the city centre. This area was playing a key role in development of the city, as within its boundaries many activities associated with shipbuilding and port industry were located. One has to mention that the Granary Island – a place located in the heart of the waterfront area – was an area of special interest for the port and shipbuilding activities, which relates also to the embankments of both Old and New Motława rivers. But the technological changes in the maritime transportation as well as wart-time destruction of the city decided about the major changes in structure of this area and shifting the port and shipbuilding operations to other sites located to the north from the city centre. Therefore, starting from the year 1945, one could observe the on-going discussion regarding the future of this area, although only in 1990-ties it was possible to actually start implementation of these ideas. At the same time – along with appearance of the demand for the types of apartments, offi ce and commercial spaces that are located on the waterfront – the urban space of Gdańsk waterfront has become interesting for both municipal authorities and developers. In result, a large amount of projects have already been implemented or planned, which contributes towards creation of the new, waterfront urban district of Gdańsk. Within its structure one can distinguish a number of particular sites, including ones still awaiting for their development chances. In the text of this article there were presented the most important parts of these plans, as well as future development directions of urban waterfront structures.
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Measurement data obtained from Weigh-in-Motion systems support protection of road pavements from the adverse phenomenon of vehicle overloading. For this protection to be effective, WIM systems must be accurate and obtain a certificate of metrological legalization. Unfortunately there is no legal standard for accuracy assessment of Weigh-in-Motion (WIM) systems. Due to the international range of road transport, it is necessary to standardize methods and criteria applied for assessing such systems’ accuracy. In our paper we present two methods of determining accuracy of WIM systems. Both are based on the population of weighing errors determined experimentally during system testing. The first method is called a reliability characteristic and was developed by the authors. The second method is based on determining boundaries of the tolerance interval for weighing errors. Properties of both methods were assessed on the basis of simulation studies as well as experimental results obtained from a 16-sensor WIM system.
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The paper provides analysis of the influence of temperature on the error of weigh-in-motion (WIM) systems utilizing piezoelectric polymer load sensors. Results of tests of these sensors in a climatic chamber, as well as results of long-term tests at the WIM site, are presented. Different methods for correction of the influence of changes in temperature were assessed for their effectiveness and compared.
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W ostatnich latach KWK Budryk udostepniła poziom 1300 m, gdzie znajduje się około 160 mln ton węgla, w tym około 120 mln ton węgla koksowego typu 35. Podjęto zadanie kompleksowej modernizacji Zakładu Wzbogacania Węgla. W artykule przedstawiono modernizację układów przesiewania, klasyfikacji i odwadniania węgla w Zakładzie Wzbogacania Węgla KWK Budryk i wdrożenie przesiewaczy firmy PROGRESS ECO sp. z o.o. sp.k. W projekcie modernizacji określono następujące wymagania techniczne dotyczące wszystkich przesiewaczy w projekcie rozbudowy Zakładu Przeróbczego KWK Budryk: - przesiewacze wibracyjne o napędzie typu liniowego z jednostką napędową umieszczoną na belce napędowej przesiewacza w postaci generatorów drgań; - napędy przesiewaczy wyposażone w urządzenie rozruchowo-hamujące; - zastosowanie łożysk głównych napędu przesiewacza o nominalnym okresie eksploatacji wynoszącym co najmniej 40 000 roboczogodzin; - wszystkie powierzchnie robocze wykonane z materiałów o wytrzymałości dla nadawy o uziarnieniu do 80 mm i odporności na ścieranie; listwy boczne oraz sita umocowane w sposób zapewniający bezawaryjną pracę, a jednocześnie łatwą i szybką wymianę; - osłony z blachy nierdzewnej; - burty boczne, belki oraz inne elementy do nich montowane połączone śrubami z zastosowaniem systemu zabezpieczającego przed korozją szczelinową oraz rozłączaniem się elementów; - zastosowanie systemu monitorowania i wizualizacji parametrów pracy, tj.: - skoku rzeszota, - temperatury pracy łożysk i stanu ich zużycia. Dostarczono trzy rodzaje przesiewaczy: - przesiewacze PWP1-1Z-2,8x6,0 realizujące alternatywnie procesy odmulania lub odsiewania, - przesiewacze PWP1-2,4x6,0 realizujące procesy odmulania, - przesiewacze PWP1-2,0x6,0 realizujące proces klasyfikacji.
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Systems of road traffic parameters measurement play a key role in the process of road traffic control, its supervision as well as in gathering and processing information for statistical purposes. Expectations of users of such systems mainly concern automation and provision of measurement continuity, possibility of selection of the measured road traffic parameters and high accuracy along with reliability of obtained results. In order to meet the requirements set for such systems, at the Department of Instrumentation and Measurement of the AGH University of Science and Technology in Cracow a new prototype system of road traffic parameters measurement - Traffic-1 - has been constructed. The innovativeness of the solution is manifested in the structure of the system that can be modified by the user adequately to current measurement needs and in the used algorithms of signals processing. The work contains a brief description of the constructed system with particular focus on the used innovations that are the result of many years of research work of the designers.
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Introduction: Trauma is one of the leading causes of death in the European Union. The European Trauma Course (ETC) is a training course that focuses on administering aid to trauma patients in a Hospital’s Emergency Department by creating an effective and well-organized trauma team. The purpose of the study is to analyze how the ETC training is evaluated by its participants and whether it is tailored to local needs. Materials and Methodology: The study includes eight courses conducted between 2010 and 2015, involving 109 medical professionals. Participants were given questionnaires where they could evaluate the various aspects of the course and comment on each of them, using a four-level scale. Finally, 78 surveys were qualified for the study. Results: The exercises were very highly rated (average 3.79 points), mainly for their interesting scenarios and station preparation. Equally well-evaluated was the short and concise method of instruction. The lowest ranked aspect was the course fee (2.41 points). There were oft en negative comments about the use of English during the training (lectures and manuals). Discussion: The opinions of Polish students were similar to those of ETC participants in other European countries. There are many interesting advantages of workshop scenarios, while the downside is the time constraint. Nevertheless, the ETC has been very successful. High ratings and positive feedback affirm the high demand for such courses in Poland.
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Background and Aim: Patients with acute pulmonary embolism (APE) associated with hemodynamic instability, i.e. high-risk APE (HR-APE), are at risk for early mortality and require urgent reperfusion therapy with thrombolysis or embolectomy. However, a considerable proportion of HR-APE subjects is not reperfused but only anticoagulated due to high bleeding risk. The aim of the present study was to assess the management of HR-APE in a single large-volume referral center. Methods: A single-center retrospective study of 32 HR-APE subjects identified among 823 consecutive patients hospitalized for symptomatic APE. Results: Out of 32 subjects with HR-APE (19 women, age 69 ± 19 years), 20 patients were unstable at admission and 12 subsequently deteriorated despite on-going anticoagulation. Thrombolysis was applied in 20 (62.5%) of HR-APE subjects, limited mainly by classical contraindications in the remainder. Percutaneous pulmonary embolectomy was performed in 4 patients. In-hospital PE-related mortality tended to be higher, albeit insignifi cantly, in the patients who developed hemodynamic collapse during the hospital course compared to those unstable at admission (67% vs. 40%, p = 0.14). Also, survival was slightly better in 22 patients treated with thrombolysis or percutaneous embolectomy in comparison to 10 subjects who received only anticoagulation (54% vs. 40%, p = 0.2). Major non-fatal bleedings occurred in 7 of 20 patients receiving thrombolysis (35%) and in 2 (17%) of the remaining non-thrombolysed 12 HR-APE subjects. Conclusions: Hemodynamically instability, corresponding to the definition of HR-APE, affects about 4% of patients with APE, developing during the hospital course in approximately one-third of HR-APE subjects. As almost 40% of patients with HR-APE do not receive thrombolytic therapy for fear of bleeding, urgent percutaneous catheter-assisted embolectomy may increase the percentage of patients with HR-APE undergoing reperfusion therapy. Further studies are warranted for a proper identification of initially stable intermediate-risk APE subjects at risk of hemodynamic collapse despite appropriate anticoagulation.
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