Wyniki wyszukiwania - BazTech

1

Influence of mineral matter on NO formation during air-staged combustion of pulverised lignite

Zacharczuk W., Hardy T.

Archivum Combustionis

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2011

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Vol. 31 nr 1-2

5-15

EN

The evolution of NO during air-staged combustion of pulverized lignite has been studied with an electrically-heated drop-tube reactor, in wide temperature and stoichiometric ratio range. In order to investigate the effect of mineral matter in lignite on NO formation, raw, demineralized and Ca-loaded lignite samples have been used. The obtained results showed that some active components in mineral matter promote NO reduction during air staging under certain combustion conditions. The maximum benefits of the catalysts presence were observed at low stoichiometric ratio region and combustion temperatures where the emission level of NO from raw lignite was apparently lower in comparison with HCl washed lignite. A similar effect has been also found for individual calcium catalyst introduced into demineralized lignite by impregnation.

2

Study of NO emission during combustion of CA-loaded pulverized lignite

Zacharczuk W., Hardy T.

Chemical and Process Engineering

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2010

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Vol. 31, z. 3

451-460

EN

The catalytic effect of calcium in lignite on NO emission during one-stage combustion process has been studied with a drop-tube reactor. It was found that Ca, added to demineralized lignite, increases NO emission level, although its catalytic effect is strongly dependent on O2 concentration and temperature while independent of type of calcium compounds used in this study.

PL

Przedstawiono wyniki badań wpływu obecności wapnia w węglu brunatnym na emisję NO podczas procesu jednostopniowego spalania w reaktorze przepływowym. Wykazano, że wapń wprowadzony do węgla demineralizowanego zwiększa emisję tlenków azotu, jednak jego katalityczna aktywność zależy od koncentracji tlenu oraz temperatury spalania, nie zależy natomiast od rodzaju związku wapnia użytego do impregnacji.

3

The Investigation of the Air Pollutants Emission During Energetic Biomass Combustion in Pulverized Chambers

Blanc O., Hardy T., Zacharczuk W.

Archivum Combustionis

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2010

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Vol. 30 nr 3

95-101

EN

In Poland, among all renewable energy sources (RES) used, biomass seems to be the most popular because of the lowest investment cost compare to the other RES. The most profitable method for biomass utilization in power engineering is its direct combustion or co-combustion with coal in steam boilers installations. One of the biomass sources might be the fast growing plants plantation. The results of the investigations on the air pollutants emission during pulverized biomass combustion are presented in this paper. The experiments were carried out in the drop-tube flow reactor in wide temperature and stoichiometric ratio range. Three kinds of energetic biomass from Polish experimental plantations have been used (willow, miscanthus, sida hermaphrodita). The obtained results show different profiles of air pollutant emission during combustion of biomass studied.

4

The use of nuclear power plant PC simulators for students and engineering staff training

Zacharczuk W., Tatarek A.

Systems : journal of transdisciplinary systems science

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2008

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Vol. 13, spec. iss. 1/2

89--95

EN

The computer simulators of nuclear power plants (NPP) with Pressurized Water Reactor (PWR), Boiling Water Reactor (BWR) and Heavy Water Reactor (HWR) has been described in this paper. The possibility of tic use of NPP simulators for educational purpose and engineering staff training has been presented, as well.

5

Development of porosity in calcium doped lignites during devolatilization and steam gasification

Kaczmarczyk J., Kordylewski W., Zacharczuk W., Hardy T.

Chemical and Process Engineering

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2008

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Vol. 29, z. 2

425-436

EN

The effect of the presence of calcium in lignites on the reactivity of chars during their steam gasification and the development of porosity, were studied. It has been confirmed that the demineralization of lignites leads to microporous structures of the products, while the presence of calcium enhances the development of mesoporosity.

PL

Przedstawiono wyniki badań wpływu obecności wapnia w węglu brunatnym na reaktywność karbonizatów zgazowanych parą wodną oraz na ich strukturę porowatą. Stwierdzono, że demineralizacja węgli brunatnych powoduje rozwój struktury mikroporowatej w produktach karbonizacji, podczas gdy obecność wapnia przyczynia się do wzrostu struktury mezoporowatej, co wpływa na zwiększenie reaktywności.

6

Katalityczna rola wapnia w reburningu węglem brunatnym

Zacharczuk W., Hardy T

Archiwum Spalania

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2006

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Vol. 6, nr 1-4

120-130

PL

W pracy przedstawiono wyniki badań wpływu obecności wapnia w węglu brunatnym na jego efektywność redukcji emisji NO metodą reburningu. Wykazano, że wprowadzony do węgli brunatnych wapń, przy użyciu wybranych jego związków, poprawia ich efektywność jako paliw reburningowych, ale tylko w zakresie niższych temperatur. Wyniki badań wskazują, że przyczyną zaniku katalitycznej aktywności wapnia w wyższych temperaturach spalania może być spiekanie cząstek CaO do większych struktur, prowadzące do pogorszenia stopnia jego dyspersji.

EN

The effect of the calcium present in lignite on the effectiveness of NO reduction in the reburning method has been presented in this paper. It was shown that Ca loaded to lignite using selected calcium compounds improved its effectiveness as a reburn fuel. This effect has been observed in the low temperature range. It was likely that loss of the catalytic activity of calcium above 1000 °C was due to the agglomeration of CaO in low rank coals.

7

The effect of calcium compounds on the reactivity of lignite chars

Kaczmarczyk J., Kordylewski W., Zacharczuk W., Hardy T.

Archivum Combustionis

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2006

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Vol. 26 nr 1-2

5-18

EN

The effect of calcium compounds present in lignite on the effectiveness of steam gasification of lignite chars has been studied at the temperature of 750° C. lignites from three Polish mines were used. Samples were demineralized with 2M HCl to remove alkali and alkaline earth metals. The demineralized lignites were loaded with Ca using: calcium acetate Ca(CH3COO)2, calcium hydroxite Ca(OH)2 and calcium carbonate CaCO3. The lignite samples were carbonized at the temperature of 900 °C in order to obtain lignite chars. The gasification process, applying steam as the oxidizing agent, was studied using thermogravimetric analysis at the temperature of 750 °C. For the process of gasification, the catalytic effect caused by the presence of calcium in lignite was found to be very important (2-7 times reaction rate acceleration). Even more important appeared to be the fact, that the effect of calcium was practically independent of the kind of calcium compound used. The inherent minerals present in raw lignite exert a similar catalytic effect to that caused by the added calcium.

8

Modyfikacja popiołu i żużla metodą witryfikacji

Kordylewski W., Zacharczuk W., Kasprzyk K.

Ochrona Powietrza i Problemy Odpadów

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2003

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Vol. 37 nr 3

84-88

PL

W artykule przedstawiono wyniki badań nad możliwością modyfikacji właściwości lotnych popiołów metodą witryfikacji. Do badań użyto popioły lotne pochodzące z polskich elektrowni. Zbadano właściwości szkieł otrzymanych w procesie witryfikacji. Badania doświadczalne przeprowadzono w reaktorze typu złoże stałe. W eksperymencie zastosowano elektryczną metodę witryfikacji. Otrzymane wyniki pokazały, że witryfikacja jest skuteczną metodą umożliwiającą modyfikację właściwości lotnych popiołów. Uzyskany w wyniku przetopu materiał miał amorficzną strukturę, a ponadto charakteryzował się dobrymi właściwościami chemicznymi i fizycznymi. Wymywalność metali ciężkich z produktów witryfikacji była bardzo mała, ponieważ zostały one wbudowane w strukturę szkła.

EN

The article presents results of research on the potential of vitrification as a method for modifying fly-ash properties. Fly-ash originating from Polish hard coal-fired power plants was used for experiments. Properties of the glasses obtained in the vitrification process were analysed. The experiments were conducted in a fixed bed reactor using electrical vitrification. The experimental data proved vitrification an effective method enabling modification of fly-ash properties. Glasses produced from fly-ash had amorphous texture and showed good chemical and physical properties including high physical durability. Leachability of heavy metals from vitrification products was very low, since the metals have been successfully immobilised in the glass structure.

9

The Influence of calcium Presence in Lignite on Conversion of Fuel Nitrogen during Pyrolysis

Zacharczuk W., Hardy T.

Archivum Combustionis

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2003

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Vol. 23 nr 1-2

63-68

EN

The effect of calcium presence in lignite on conversion of fuel nitrogen (Nf) to char-N during pyrolysis has been investigated. The experiment was carried out in the fixed bed reactor at the temperature in the range of 700 - 1000 C. At first, the lignite was demineralized with HCl, in order to exclude mineral matter in the coal used. Next, Ca2+ ions were introduced into the lignite samples by using aqueous solution of calcium acetate Ca(CH3COO)2. The influence of calcium addition in lignite on the Nf conversion was studied using raw, demineralized and impregnated coal samples. The obtained results show that calcium Ca presence in lignite decreases yield of char-N during pyrolysis (decreases the coal-N conversion to char-N). Demineralization of lignite with HCl washing increases yields of char-N during pyrolysis. The addition of 3% Ca to the demineralized coal shows almost the reverse effect. It is likely that fine particles of CaO derived from Ca2+ ions present in raw and impregnated coal promote Nf conversion to N2 instead to char-N during pyrolysis.

10

Modification of Fly-Ash by Vitrification

Kasprzyk K., Kordylewski W., Zacharczuk W.

Archivum Combustionis

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2003

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Vol. 23 nr 1-2

21-30

EN

The results of preliminary experimental studies concerning the prevention of the leaching of heavy metals from fly ash by vitrification are presented in the paper. The problem considered relates to the potential utilisation of fly ash in water treatment. The laboratory studies were performed using the plasma method of vitrification. The fly ash used was collected from thermal power plants: firing lignite and hard coal. Soluble salts of four heavy metals (cadmium, chromium, lead and zinc) were used for doping the fly ash. Leachability of the heavy metals used from fly-ash samples and from the products of vitrification was examined according to Polish regulations. The possibility of improvement of mechanical properties of vitrification products by heat treatment was considered. Crystallisation of minerals in the vitrification glass was investigated using the XRD method. The effect of heat treatment was examined by hardness measurement on the glass and glass-ceramic.