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Abstrakt

Bilingualism has long been observed in Silesia, a part of Poland which lies on the border between three cultures and languages: Polish, Czech and German. Some lin-guists consider Silesian one of the Polish dialects, others think it should be treated as a separate language. During the communist times the inhabitants of Upper Silesia were discouraged from using the local dialect at school or in public institutions. The situation has changed a lot since 1989 with the promotion of regional studies. Short characteristics of Silesian will be presented in the fi rst part of the paper.The main part of the project presents the results of a questionnaire which focuses on young people’s attitudes towards Silesian. The respondents (100 Polish students of English philology) fall into two groups – half of them identify themselves with the region and the other half do not. How many respondents speak Silesian? Where do they use it and how do they evaluate it? What is the linguistic stereotype of a person living in Upper Silesia? These are just a few questions that suggest themselves in the context of the study.

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Autorzy i Afiliacje

Urszula Wieczorek

Abstrakt

The first record of an oriental, alien aphid species belonging to the genus Takecallis, associated with the cold hardy bamboo Fargesia rufa T.P.Yi, collected in Słupsk, Pomeranian Voivodeship, Poland, is provided. The increase in worldwide trade of new frost-resistant ornamental bamboo varieties as a source of introducing alien species of insects in Europe and the role of garden centers as potential dispersal sites for these species is discussed.
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Autorzy i Afiliacje

Karina Wieczorek
1

  1. Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, Katowice, Poland

Abstrakt

The paper presents a thermodynamic analysis of the removal of an inert gas from the tank using the vapor of liquefied petroleum gas cargo (called cargo tank gassing-up operation). For this purpose a thermodynamic model was created which considers two extreme cases of this process. The first is ‘piston pushing’ of inert gas using liquefied petroleum gas vapour. The second case is the complete mixing of both gases and removal the mixture from the tank to the atmosphere until desired concentration or amount of liquefied petroleum gas cargo in the tank is reached. On the example of nitrogen as inert gas and ethylene as a cargo, by thermodynamic analysis an attempt was made to determine the technical parameters of the process, i.e., pressure in the tank, temperature, time at which the operation would be carried out in an optimal way, minimizing the loss of cargo used for gassingup. Calculations made it possible to determine the amount of ethylene used to complete the operation and its loss incurred as a result of total mixing of both gases.
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Autorzy i Afiliacje

Agnieszka Wieczorek
1

  1. Gdynia Maritime University, Morska 81–87, 81-225 Gdynia, Poland

Abstrakt

The paper is a thermodynamics analysis of the removal of any inert gas from the tank using the vapors of any liquefied petroleum gas cargo (called cargo tank gassing-up operation). For this purpose, a thermodynamic model was created which considers two boundary cases of this process. The first is a ‘piston pushing’ of inert gas using liquefied petroleum gas vapour. The second case is complete mixing of both gases and removal the mixture from the tank to the atmosphere until desired concentration or amount of liquefied petroleum gas cargo in the tank is reached. Calculations make it possible to determine the amount of a gas used to complete the operation and its loss incurred as a result of total mixing of both gases.
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Autorzy i Afiliacje

Agnieszka Wieczorek
1

  1. Gdynia Maritime University, Morska 81–87, 81-225 Gdynia, Poland

Abstrakt

Zaprezentowano wyniki badań biofiltracji modelowych strumieni gazowych zawierających toluen i p-ksylen na kolumnach wypełnionych dwoma rodzajami niemodyfikowanych kompostów. W trakcie pomiarów określono szybkość i skuteczność biofiltracji w funkcji stężenia zanieczyszczeń i szybkości strumienia gazów. Maksymalne, średnie dla górnej sekcji kolumny, wartości szybkości rozkładu zanieczyszczeń wyniosły ok. 80 g/m3/h, a dla całej kolumny 40 g/m3/h. Stwierdzono znaczne fluktuacje skuteczności i szybkości biofiltracji, przy zbliżonych, dobrze kontrolowanych parametrach pomiarów. Najbardziej prawdopodobną ich przyczyną były zmiany trudno sterowalnej wilgotności złoża.
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Autorzy i Afiliacje

Andrzej Wieczorek

Abstrakt

W pracy zaprezentowano wyniki badań biofiltracji gazów odlotowych z emalierni drutów nawojowych. Gazy te zawierały ponad 50 zanieczyszczeń, w tym fenol i krezole. Biofiltrację prowadzono przy liniowej szybkości przepływu gazów 0,28 cm/s na złożu kompostowym. Uzyskano ponad 99%-ową skuteczność całego procesu. Zaobserwowano istotne zmniejszenie stężenia zanieczyszczeń już w nawilżaczu.
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Autorzy i Afiliacje

Andrzej Wieczorek

Abstrakt

Observing nature since time immemorial, mankind has always noticed the surprising regularities evidenced by many biological phenomena. Mathematical modeling is now helping explain them.
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Autorzy i Afiliacje

Ryszard Rudnicki
Radosław Wieczorek
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Abstrakt

This paper presents the influence of cooling water regulation on power plant net efficiency. It was examined whether, for the non-nominal low-pressure turbine load, it is justified to reduce the cooling water pump load, and how it would affect the unit net efficiency. Calculations for two types of power units were carried out: with condensing and extractioncondensing turbine. The tested condensing power plant consists of three surface condensers. The calculation included four condensers’ connections set up on the cooling water side to check how the cooling water system pressure drop affects the net unit performance. The result has confirmed that implementing serial connection decreases net efficiency when cooling water flow regulation is used, but the mixed connection should be applied when pump load is not controlled. It was proved that the cooling water flow control gives a profit for both units. Net efficiency for combined heat and power plant can be improved by 0.1–0.5 pp, the gain is remarkable below 60% of the low-pressure turbine part load. Flow control implementation in the unit with condensing turbine water control gives a similar profit just below 80% of the turbine load. Next, an influence of the additional limitations of a cooling water system (minimal total pump head, cooling tower) affecting the feasibility of implementing the water control has been considered. Applying a multi-cell forced draft cooling tower does not have a significant impact on results, but when a natural draft cooling tower is used, the flow control range is strongly reduced.
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Bibliografia

[1] Chmielniak T., Łukowicz H.: Modeling and optimization of coal power units with CO2 capture. WPS, Gliwice 2015 (in Polish).
[2] Chmielniak T., Łukowicz H.: Condensing power plant cycle assessing possibilities of improving its e?ciency. Arch. Thermodyn. 31(2010), 3, 105–113.
[3] Grzesiczek E., Mendecki J., Komarnicki Z.: Optimization of cooling water flow in 225 MW turbine condenser. Energetyka (2007), 8, 574–575.
[4] Rusak J.: Reduction of auxiliary energy consumption in TAURON Wytwarzanie S.A. on the example of cooling water systems modernization. Energetyka (2013), 1, 43–47.
[5] Laskowski R.: Wybrane zagadnienia modelowania i optymalizacji skraplaczy energetycznych i wymienników regeneracyjnych. Warszawa: Oficyna Wydawnicza Politechniki Warszawskiej, 2018.
[6] Laskowski R., Smyk A., Rusowicz A., Grzebielec A.: Optimization of the cooling water mass flow rate under variable load of a power unit. Appl. Therm. Eng. 191(2021), 116874.
[7] Gardzilewicz A., Błaszczyk A., Głuch J.: Operating and economic conditions of cooling water control for marine steam turbine condensers. Pol. Marit. Res. 18(2011), 3(70), 48–54.
[8] Harish R., Subhramanyan E.E., Madhavan R., Vidyanand S.: Theoretical model for evaluation of variable frequency drive for cooling water pumps in sea water based once through condenser cooling water systems. Appl. Therm. Eng. 30(2010), 2051–2057.
[9] Xia L., Liu D., Zhou L., Wang P., Chen Y.: Optimization of a seawater oncethrough cooling system with variable speed pumps in fossil fuel power plants. Int. J. Therm. Sci., 91(2015), 105–112.
[10] Dobkiewicz-Wieczorek E.: Cooling water mass flow optimization for low load of condensing turbine including CHP turbine. Rynek Energii (2020), 6, 15–20.
[11] Dobkiewicz-Wieczorek E.: Influence of surface condensers connection configuration on power plant unit performance. Arch. Thermodyn. 41(2020), 4, 115–145.
[12] Revised Release on the IAPWS Industrial Formulation 1997 for the Thermodynamic Properties of Water and Steam, The International Association for the Properties of Water and Steam. Lucerne 1997.
[13] Dobkiewicz-Wieczorek E.: Method for calculating the exhaust steam pressure of a condensing turbine. Energetyka (2019), 11, 725–730.
[14] KSB, Tips for the correct design of pumping stations equipped with submersible pumps. https://www.ksb.com/blob/173022/c7fe2d9f8e342c707efa5e0966136752/pumpenstation-download-data.pdf (accessed 6 Oct. 2021). [15] PN-76/M-34034 Pipelines – Principles of pressure loss calculations.
[16] EMBER, Average monthly wholesale electricity prices. https://ember-climate.org/european-electricity-transition/ (accessed 6 Oct. 2021).
[17] Market electrical energy price. https://wysokienapiecie.pl/40547-o-ile-wzrosna-cenypradu-w-2022-policzylismy/ (accessed 6 Oct. 2021).
[18] PSE, Daily market electrical energy price. https://www.pse.pl/dane-systemowe/funkcjonowanie-rb/raporty-dobowe-z-funkcjonowania-rb/podstawowe-wskazniki -cenowe-i-kosztowe/rynkowa-cena-energii-elektrycznej-rce (accessed 6 Oct. 2021).
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Autorzy i Afiliacje

Ewa Dobkiewicz-Wieczorek
1

  1. Silesian University of Technology Department of Power Engineering and Turbomachinery, Konarskiego 18, 44-100, Gliwice, Poland

Abstrakt

This paper presents a comparison of three surface condenser connection setups on the cooling water side. Four connections were considered, namely serial, mixed and two parallel ones. The analysis was conducted based on the calculated heat balances of proposed power unit for nominal and not nominal parameters for tested connections. Thermodynamic justification for the use of more complex configuration was verified. The exhaust steam pressure calculation was presented. Three methods of computing the heat transfer coefficient based on characteristic numbers, namely the Heat Exchange Institute (HEI) method, and the American Society of Mechanical Engineers (ASME) standard, were used. Calculation results were validated with the real data. The most accurate model was indicated and used in heat balance calculations. The assumptions and simplifications for the calculations are discussed. Examples of the calculation results are presented.

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Autorzy i Afiliacje

Ewa Dobkiewicz-Wieczorek

Abstrakt

The research aimed to use chemical, geochemical, and ecotoxicity indices to assess the heavy metals content in soils with different degrees of exposure to human pressure. The research was conducted in southern Poland, in the Malopolska (Little Poland) province. All metal contents exceeded geochemical background levels. The highest values of the Igeo index were found for cadmium and were 10.05 (grasslands), 9.31 (forest), and 5.54 (arable lands), indicating extreme soil pollution (class 6) with this metal. Mean integrated pollution index (IPI) values, depending on the kind of use, amounted to 3.4 for arable lands, 4.9 for forests, and 6.6 for grasslands. These values are indicative of a high level of soil pollution in arable lands and an extremely high level of soil pollution in grasslands and forests. Depending on the type of soil use, Vibrio fischeri luminescence inhibition was from -33 to 59% (arable lands), from -48 to 78% (grasslands), and from 0 to 88% (forest). Significantly the highest toxicity was found in soils collected from forest grounds.

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Autorzy i Afiliacje

Agnieszka Baran
Jerzy Wieczorek

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