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1

Influence of titanium dioxide modification on the antibacterial properties

Rokicka P., Markowska-Szczupak A., Kowalczyk Ł., Kowalska E., Morawski A. W.

Polish Journal of Chemical Technology

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2016

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Vol. 18, nr 4

56--64

EN

Antibacterial properties of 15 titania photocatalysts, mono- and dual-modified with nitrogen and carbon were examined. Amorphous TiO2 , supplied by Azoty Group Chemical Factory Police S.A., was used as titania source (Ar-TiO2 , C-TiO2 , N-TiO2 ;2 and N,C-Ti2 2 calcined at 300°C, 400°C, 500°C, 600°C, 700°C). The disinfection ability was examined against Escherichia coli K12 under irradiation with UV and artificial sunlight and in dark conditions. It has been found the development of new photocatalysts with enhanced interaction ability with microorganisms might be a useful strategy to improve disinfection method conducted under artificial sunlight irradiation. The efficiency of disinfection process conducted under artificial sunlight irradiation with carbon (C-TiO2 ) and carbon/nitrogen (N,C-TiO2 ) photocatalysts was similar as obtained under UV irradiation. Furthermore, during dark incubation, any toxicity of the photocatalyst was noted.

2

Thermodynamic analysis and profitability study of a power unit with an added CO2 capture plant

Kowalczyk Ł., Niegodajew P., Drobniak S., Elsner W.

Journal of Power Technologies

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2016

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Vol. 96, nr 4

276--284

EN

Concerns over greenhouse gas emissions are driving a requirement for newly built coal power units to satisfy the so-called “capture ready” conditions. This paper presents the a thermo-economic analysis supplemented by a cost evaluation of a power unit for ultra-supercritical parameters expanded by an amine-based CO2 capture plant. The analysis was performed with the use of an integrated package containing the IPSEpro, MATLAB and Revenue Requirement Method implemented in MOExcel. The 0D model of a post combustion capture installation was developed based on complex CFD calculations of the absorber and stripper. A number of CFD simulations were conducted to create a large database, which was then utilized to develop suitable correlations describing the process Thermodynamic and economic calculations were performed in respect of a power plant coupled with a CO2 separation unit for a varying ratio of amine solvent to the exhaust gas stream (L/G). A local minimum for reboiler heat duty was found for L/G≈3.5 revealing the optimal post combustion capture configuration. It was observed that complementing the power unit with a post-combustion capture (PCC) installation causes a slight increase in the investment costs due to the drop in efficiency, but more important is the rise in total cost due to the investment associated with the CO2 capture plant. It was found that about 14 years is required to compensate the investment cost of the PCC installation.

3

Evaluation of IPSEpro extended by MATLAB applied to steam turbine cycle analysis

Elsner W., Kowalczyk Ł., Marek M.

Journal of Power Technologies

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2015

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Vol. 95, nr 3

192--200

EN

This paper investigates thermodynamic optimization of a supercritical coal fired power plant. The main goal of the study was to assess IPSEpro software combined with MATLAB environment, aimed at multiobjective optimization of the thermal cycle in a relatively short timeframe. To verify the methodology, calculations were carried out using the IPSEpro (standalone) approach and IPSEpro-MATLAB with fmincon function. The decision functions were: thermal efficiency, gross power efficiency and total power load. It was shown that the results obtained with the IPSEpro standalone approach are similar to those obtained with the IPSEpro- MATLAB package. This means that the IPSEpro-MATLAB approach can be successfully used in future calculations. The evident benefit of the newly developed methodology is a significant reduction in computational time compared to the referenced method. It was shown that the computational time depends on both the methodology and the chosen objective function. The results show that the detected optimal point also depends on the shape of the objective function distribution. Optimization of the thermodynamic parameters of the sample ultra-supercritical power plant enables an increase in output power from 900 MW to 909.44 MW.

4

Thermoeconomic analysis of supercritical coal fired power plant using RRM method

Kowalczyk Ł., Elsner W., Drobniak S.

Energetyka

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2013

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nr 11

803--807

EN

The paper presents the thermoeconomic analysis for a novel concept of an ultra-supercritical coal-fired steam cycle. The main purpose of this paper was to show basic assumption of RRM method which was used for three different structural configurations of a power unit. The calculations were performed with IPSEpro and RRM methods. Our results confirm the literature data that RRM method is the most suitable one for the energy sector. Additionally this method is one of the most advanced procedures used in the financial analysis. It allows to estimate investment costs for which the revenues provide minimum acceptable cost return for investors. This method was implemented for IPSEpro and MO Excel software. For PEC calculation a new library, called APP_ECO_Lib, was created. Three cases with different structure configurations were analysed. From the viewpoint of thermodynamic the case nr 3 is the most effective system, as the increase of efficiency seems to be sufficient to compensate investment cost associated with structural change. It should be mentioned that some of calculation uncertainty is related with material factors. The analyses have shown that calculations for critical and under-critical steam cycles are sufficiently reliable. However, there is a lack of data for new materials which will be used for design of for ultra-supercritical steam cycle components, that is why calculations for these cases may be biased with some error which is difficult to estimate.

PL

Artykuł przedstawia analizę termoekonomiczną nowatorskiej koncepcji dla bloków realizujących cykl parowy o parametrach supernadkrytycznych i opalanych węglem kamiennym. Głównym celem tego artykułu jest pokazanie podstawowych założeń metody RRM, która została wykorzystana dla trzech różnych konfiguracji struktury bloku energetycznego. Obliczenia zostały wykonane przy pomocy metod IPSEpro i RRM. Osiągnięte przez nas wyniki potwierdzają publikowane dane, że metoda RRM jest najbardziej przydatną metodą dla sektora energetycznego. Metoda ta została zaimplementowana dla oprogramowania IPSEpro i MO Excel. Na użytek obliczeń PEC została opracowana nowa biblioteka o nazwie APP_ECO_Lib. Przeanalizowano trzy przypadki różnych konfiguracji strukturalnych. Z punktu widzenia termodynamiki, przypadek nr 3 jest systemem najbardziej efektywnym, jako że wzrost wydajności wydaje się być wystarczający dla kompensacji kosztów poniesionych w związku ze zmianą strukturalną. Analizy wykazują, że obliczenia przeprowadzane dla krytycznego i podkrytycznego cyklu parowego są wystarczająco wiarygodne. Brakuje jednakże danych dotyczących nowych materiałów, które będą wkrótce wykorzystywane przy projektowaniu elementów instalacji na potrzeby supernadkrytycznych cykli parowych. Dlatego też obliczenia dla takich przypadków mogą być obciążone pewnymi błędami, których wartości są trudne do oszacowania.

5

Comparative analysis of optimisation methods applied to thermal cycle of a coal fired power plant

Kowalczyk Ł., Elsner W.

Archives of Thermodynamics

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2013

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Vol. 34, no. 4

175--186

EN

The paper presents a thermodynamic optimization of 900 MW power unit for ultra-supercritical parameters, modified according to AD700 concept. The aim of the study was to verify two optimisation methods, i.e., the finding the minimum of a constrained nonlinear multivariable function (fmincon) and the Nelder-Mead method with their own constrain functions. The analysis was carried out using IPSEpro software combined with MAT-LAB, where gross power generation efficiency was chosen as the objective function. In comparison with the Nelder-Mead method it was shown that using fmincon function gives reasonable results and a significant reduction of computational time. Unfortunately, with the increased number of decision parameters, the benefit measured by the increase in efficiency is becoming smaller. An important drawback of fmincon method is also a lack of repeatability by using different starting points. The obtained results led to the conclusion, that the Nelder-Mead method is a better tool for optimisation of thermal cycles with a high degree of complexity like the coal-fired power unit.

6

Utlenianie odorowego amoniaku na katalizatorach tytanowych modyfikowanych metalami szlachetnymi

Kowalczyk Ł., Szynkowska M. I.

Przemysł Chemiczny

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2012

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T. 91, nr 5

801-804

PL

Badano katalityczne i fotokatalityczne (UV i Vis) utlenianie amoniaku w fazie gazowej w reaktorze przepływowym. Stosowano katalizatory tytanowe: niemodyfikowany oraz po modyfikacji metalami szlachetnymi (Pt, Pd, Au) w których jako nośnik zastosowano krzemionkę. Katalizatory zostały przygotowane metodą mokrej impregnacji. Dzięki zastosowaniu domieszkowania metalami szlachetnymi możliwe było znaczne poprawienie aktywności katalizatorów, co widoczne jest zwłaszcza w przypadku platyny i palladu. Stwierdzono również wyraźny wpływ naświetlania próbek niemodyfikowanych światłem z zakresu UV oraz Vis na konwersję amoniaku w badanym zakresie temperatur. W przypadku próbek modyfikowanych metalami szlachetnymi ten wpływ nie był już tak wyraźny.

EN

NH₃ was chem. and photochem. oxidized with O₂ in He on Pt, Pd or Au-modified TiO₂/SiO₂ catalysts (sp. surface 306–380 m²/g) under UV or visible light irradn. at 100–700°C. The modification with Pt resulted in the highest increase of NH₃ conversion under UV irradn.

7

Analiza możliwości modyfikacji struktury obiegu bloków węglowych pracujących na parametry ultranadkrytyczne

Elsner W., Kowalczyk Ł.

Modelowanie Inżynierskie

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2012

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T. 13, nr 44

57-64

PL

W artykule przedstawiono analizę wpływu modyfikacji obiegu cieplnego (wprowadzenie układ krzyżowego i turbiny pomocniczej) na parametry ultranadkrytyczne bloku węglowego (700/720 C) dla przypadku z pojedynczym i podwójnym przegrzewem międzystopniowym. Wprowadzenie tak wysokich parametrów pary powoduje konieczność zastosowania wysokostopowych materiałów na regenerację wysokoprężną oraz wzrost spiętrzenia temperatur i w konsekwencji duże straty egzergii. Problem ten można rozwiązać, wprowadzając do obiegu turbinę pomocniczą zasilaną z wylotu części HP. Jak wykazano, dołożenie do obiegu cieplnego schładzacza pary nie daje istotnych zysków, jeżeli chodzi o sprawność, jednak pozwala na zmniejszenie parametrów pary upustowej podawanej na związany z nim wymiennik oraz na zmniejszenie powierzchni wymiany ciepła.

EN

This paper presents an analysis of the impact of thermal cycle modification (introduction of desuperheater and auxiliary turbine) on the parameters of ultra-supercritical coal unit (700/720 C) for the case with single and double steam reheat system. Application of such high steam parameters result in the need for expensive high alloys and cause an increase of bleed steam temperature and so the exergy loss. This problem can be solved by the introduction of the auxiliary turbine (T-T) supplied from the outlet of the HP. As it was shown, application of desuperheater to the thermal cycle do not give significant gains in terms of efficiency. However, it allows for reduction of bleeding steam parameters directed to the associated heat exchanger and for reduction of its heat exchange surface.

8

Calculation of a 900 MW conceptual 700/720ºC coal-fired power unit with an auxiliary extraction-backpressure turbine

Stępczyńska K., Kowalczyk Ł., Dykas S., Elsner W.

Journal of Power Technologies

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2012

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Vol. 92, nr 4

266--273

EN

This paper presents the calculations for different configurations of a 900 MW power unit for advanced 700/720°C ultra-supercritical steam parameters with a single and double steam reheat. The use of such high parameters, especially the reheated steam temperature, involves thermodynamic and material problems related to high temperature differences in the feed water heaters. In relation to this, a concept of the modification of the feed water heaters system by using an auxiliary extraction-backpressure turbine fed with steam from the cold reheat steam line is presented. The steam from the bleeds and the turbine outlet is directed to regenerative heaters fed in the classical system from the intermediate pressure turbine, which reduces the temperature differences in these exchangers and simplifies the main turbine IP part structure.

9

Numerical thermodynamic optimization of supercritical coal fired power plant with support of IPSEpro software

Elsner W., Kowalczyk Ł., Marek M.

Archives of Thermodynamics

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2012

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Vol. 33, no. 3

101-110

EN

The paper presents a thermodynamic optimization of supercritical coal fired power plant. The aim of the study was to optimize part of the thermal cycle consisted of high-pressure turbine and two chosen high-pressure feed water heaters. Calculations were carried out using IPSEpro software combined with MATLAB, where thermal efficiency and gross power generation efficiency were chosen as objective functions. It was shown that the optimization with newly developed framework is sufficiently precise and its main advantage is the reduction of computation time on comparison to the classical method. The calculations have shown the tendency of the increase in efficiency, with the rise of a number of function variables.

10

Thermodynamic analysis of a thermal cycle of supercritical power plant

Elsner W., Kowalczyk Ł., Niegodajew P., Drobniak S.

Mechanics and Mechanical Engineering

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2011

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Vol. 15, nr 3

217-225

EN

The study presented in this paper deals with the analysis of operating conditions of a modern supercritical power plant. The 460 MW reference thermal cycle, which is based on the Łagisza supercritical, coal fired power plant was selected for this study. The thermodynamic analysis was performed with the use of the industrial software package IPSEpro, designed for power plant engineering. The main objective was to demonstrate the role of supercritical parameters in enhancing the efficiency of the thermodynamic process. It was done among the others by the comparative analysis of two thermal cycles, one working with standard and the other with supercritical parameters. Apart from nominal operating conditions part load operation was analyzed.

11

Właściwości fizykochemiczne oraz aktywność TiO2/SiO2 w reakcji utleniania amoniaku

Kowalczyk Ł., Szynkowska M, I., Góralski J., Paryjczak T.

Przemysł Chemiczny

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2010

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T. 89, nr 4

426-429

12

Oxidation of Thiophene over Copper and Manganesem Based Oxides Modified with Pt and Pd

Szynkowska M. I., Węglińska A., Kowalczyk Ł., Paryjczak T.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 6

1163-1172

EN

Copper and manganese-based catalysts (5 per cent Cu/Al2O3, 5 per cent Mn/Al2O3) modified with different amount of Pt or Pd (0.2 or 1 wt. per cent) have been studied in oxidation of thiophene. The activity experiments reveal that samples containing Cu display higher activity for thiophene oxidation in relation to manganese-based catalysts. It is shown that lower activity of Mn catalyst is accompanied by pronounced non-homogenous distribution of Mn phase on the catalyst surface and lower reducibility. Further more, catalytic and reduction be haviour of monometallic catalysts is in fluenced by the presence of small amounts of Pt or Pd, suggesting synergism of the components of bimetallic catalysts.

13

Fotokatalityczne unieszkodliwianie odorów - amoniak

Kuśmierek E., Chrześcijańska E., Szynkowska M., I., Kowalczyk Ł., Góralski J., Paryjczak T.

Chemik

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2009

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Vol. 62, nr 11

407-413

PL

Opisano możliwość zastosowania fotokatalitycznego utleniania, jako alternatywy powszechnie stosowanych metod unieszkodliwiania odorów. Scharakteryzowano zasadę działania fotokatalizatorów na przykładzie TiO2. Znaczący wpływ na efektywność procesu fotokatalitycznego ma temperatura, wilgotność i zawartość tlenu w unieszkodliwianej mieszaninie gazowej. W czasie procesu może następować dezaktywacja fotokatalizatora, ale można go regenerować. Opisano parametry charakteryzujące wydajność procesu fotokatalitycznego. W celu wykorzystania światła słonecznego do aktywacji fotokatalitycznej TiO2, stosuje się modyfikację tego fotokatalizatora różnymi metodami. Przedstawiono fotokatalityczne utlenianie amoniaku, jednego z najczęściej występujących odorów.

EN

Chemical properties, practical applications, advantages and risk for environment and for human (animal) health of oxygen allotrope - ozone, were briefly presented. The toxicity of ozone as well as possible use of this gas to water ozonization, room disinfection (neutralization of ammonia and other odorous compounds), preservation of food etc. were described. The methods of ozone detection both in air and water and moreover the equipment to ozonization were presented. Finally, short review of results of author's investigation concerning the use of ozone in the livestock building was made.