PL
 |
EN
Ograniczanie wyników
Czasopisma help
  1. 9 Combustion Engines
  2. 2 Polish Journal of Chemical Technology
  3. 1 Bulletin of the Polish Academy of Sciences. Chemistry
  4. 1 Chemia i Inżynieria Ekologiczna
  5. 1 Chemical and Process Engineering
Więcej...
Autorzy help
  1. 4 Jastrząb K.
  2. 2 Czerwiński J.
  3. 2 Kaczmarczyk K.
  4. 2 Kapusta Łukasz Jan
  5. 2 Motak Monika
Więcej...
Lata help
  1. 2 2023
  2. 2 2022
  3. 1 2021
  4. 1 2020
  5. 2 2019
Więcej...
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 23

Liczba wyników na stronie
first rewind previous Strona / 2 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  selective catalytic reduction
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 2 next fast forward last
1
Content available Numerical evaluation of urea-mixing devices for close-coupled selective catalytic reduction systems
Kaźmierski Bartosz Grzegorz, Kapusta Łukasz Jan
Combustion Engines
|
2023
|
R. 62, nr 2
84--93
EN
The following research presents a numerical evaluation of existing and conceptual urea-mixing devices used in close-coupled (to the engine) selective catalytic reduction (SCR) systems. The analysis was aimed at the assessment of urea-mixing devices that could considerably enhance the reduction of nitrogen oxides from the diesel-engine combustion process under a wide range of operating conditions, including cold starts. The analysis showed that replacing blade-equipped static mixers with perforated stationary mixing devices may provide a more uniform spatial distribution of ammonia at the inlet to the SCR catalyst and reduce pressure drops generated by mixing devices. Moreover, the conceptual mixing devices, based on combinations of the blade and perforated mixers to develop intensive turbulence, enabled the increase of the mixing length leading to effective decomposition of the urea-water solution (UWS), and provided uniform spatial distribution of ammonia, even for the small-sized mixing systems. However, the intensive mixing was often associated with a significant rise in the pressure drop.
2
Content available Comparative analysis of the heat balance results of the selected Tier III-compliant gas-fuelled two-stroke main engines
Korlak Kamil
Combustion Engines
|
2023
|
R. 62, nr 2
24--28
EN
Two-stroke engines are distinguished by the highest overall efficiency among all main engines. This is not only due to the low speed, and large piston stroke, but also to the high combustion temperature, which results in an increase in nitrogen oxides (NOx) emission. Technical solutions applied to bring main engines into compliance with current NOx emission standards set by the Tier III limits include the use of SCR and EGR systems, the implementation of the Otto cycle, and the application of liquified natural gas (LNG) as the low-emission fuel. Impact of the available Tier III-compliant technologies on the heat balance results is analysed using the example of the currently most popular dual-fuel main engines, i.e. WinGD X92DF and MAN G95ME-C10.5-GI. The possibilities of waste heat recovery in the electricity generation process and thereby improving the ship energy efficiency are discussed.
3
Content available Assessment of retrofit devices for the Horizon 2020 Cleanest Engine and Vehicle Retrofit Prizes
Giechaskiel Barouch, Suarez-Bertoa Ricardo, Melas Anastasios, Selleri Tommaso, Maggiore Maurizio
Combustion Engines
|
2022
|
R. 61, nr 3
7--34
EN
The Horizon 2020 prizes aimed at the development of retrofit and engines that would reduce pollution. The Retrofit prize had a winner, while the Engine prize not. In this paper we present the innovations that were tested at the Joint Research Centre (JRC) of the European Commission, and not awarded. One was a “condensation” aftertreatment device, two were devices inserted in the fuel supply system, and one a selective catalytic reduction (SCR) for NOx system. The testing of the “condensation” aftertreatment device showed that it could not with-stand the high exhaust gas temperatures. The results of the two fuel systems showed that they could not control efficiently the NOx emissions. The reductions of the pollutants were negligble for the levels that the prizes were aiming. The SCR system did not achieve any significant reduction of NOx, probably due to a malfunction of the device.
4
Content available Ammonia CI engine aftertreatment systems design and flow simulation
Kuta Kacper, Nadimi Ebrahim, Przybyła Grzegorz, Żmudka Zbigniew, Adamczyk Wojciech
Combustion Engines
|
2022
|
R. 61, nr 3
3--10
EN
Investigation of exhaust emissions and ammonia flow behavior in the exhaust system incorporating with Selective Catalytic Reduction (SCR) unit is discussed. An aftertreatment system is designed to work without additional urea injection. This study is focused on obtaining optimal parameters for catalysis. Its effectiveness is considered as a function of basic parameters of exhaust gases mixture and SCR material characteristics. A 3D geometry of SCR with porous volume has been simulated using Ansys Fluent. Moreover, a 1D model of ammonia dual-fuel CI engine has been obtained. Results were focused on obtaining local temperature, velocity, and exhaust gases composition to predict optimal probes placement, pipes insulation parameters, and characteristic dimensions.
5
Content available A conceptual design and numerical analysis of the mixerless urea-SCR system
Kaźmierski Bartosz, Górka Krzysztof, Kapusta Łukasz Jan
Combustion Engines
|
2021
|
R. 60, nr 4
12--20
EN
In the present study, an innovative design of a urea-selective catalytic reduction (SCR) system without conventional mixing elements was developed. The aim was to obtain a high degree of urea decomposition, and uniform ammonia distribution at the inlet to the catalyst, while minimising the liquid film deposition and keeping the compact design. The concept of the design was based on creating high turbulence and elongating the flow paths of the droplets. The design was verified through a series of numerical simulations based on the Reynolds-averaged Navier-Stokes (RANS) approach and a discrete droplet model (DDM) spray representation. The analysis included various operating conditions as well as subcooled and superheated sprays. A uniform ammonia distribution was achieved regardless of the operating points and spray properties. Additionally, in the case of a flash-boiling injection, a further reduction of the wall film was observed.
6
Content available Modified bentonite-derived materials as catalystsfor selective catalytic reduction of nitrogen oxides
Szymaszek Agnieszka, Kubeł Maciej, Samojeden Bogdan, Motak Monika
Chemical and Process Engineering
|
2020
|
Vol. 41, nr 1
13–-24
EN
In the last few years, cationic layered clays, including bentonites have been investigated as potentialcatalysts for SCR DeNOxsystems. In this work, bentonite as the representative of layered clays wasmodified in order to obtain an alternative, low-cost NH3–SCR catalyst. Samples of raw clay wereactivated with HCl or HNO3, treated with C2H2O4and subsequently pillared with alumina by the ion-exchange. Afterwards, the modified materials were impregnated with iron and copper. The obtainedcatalysts were characterized by XRD and FT-IR. SCR catalytic tests carried out over analyzed samplesindicated the conversion of NO of approximately 90% for the most active sample. The type of acidused for modification and the type of active phase strongly influenced the catalytic properties of theanalyzed materials.
7
Content available The influence of holmium on catalytic properties of Fe or Cu-modified vermiculites
Samojeden Bogdan, Grzybek Teresa, Kowal Joanna, Szymaszek Agnieszka, Jabłońska Magdalena, Gläser Roger, Motak Monika
Physicochemical Problems of Mineral Processing
|
2019
|
Vol. 55, iss. 6
1484--1495
EN
Natural layered clay, vermiculite, was modified and tested as catalyst for the selective catalytic reduction of NOx with ammonia (NH3-SCR). Its modification included the application of the blowing agent (azodicarbonamide), acid treatment and pillaring with Al2O3. Active phase (transition metals: Cu or Fe) was introduced via impregnation. The obtained materials were characterized by N2 sorption (texture), XRD (structure), DR-UV-Vis (oxidation state and aggregation of the active phase), H2-TPR (reducibility of the active phase), in situ DRIFTS (types of adsorbed species due to contact of the sample NH3) and NH3-TPD (type/strength of the acidic sites). The initial modification procedures (treatment with azodicarboamide) resulted in the increase of specific surface area of vermiculite. The introduction of transition metal ions provided a significant amount of acidic sites. The promoting impact of holmium was confirmed by the increased strength of the sites. The highest catalytic activity was exhibited by the sample Fe-containing vermiculite and doped with Ho.
8
Content available Experimental research and CFD analysis of flow parameters in a SCR system for the original part and WALKER’s replacement
Kurzydym Damian, Klimanek Adam, Żmudka Zbigniew
Combustion Engines
|
2019
|
R. 58, nr 4
13--20
EN
The article presents the results of experimental research and their comparison with CFD simulations for the original selective catalytic reduction system and WALKER replacement. The research was performed to develop the WALKER universal mixer. The SCR prototype without mixer and with the proposed mixer were tested and compared with the original VW part. The next step was reverse engineering, which consisted in scanning the tested parts with a laser and processing their point cloud in Leios2 program. Reverse engineering has allowed the reconstruction of 3D geometry of the tested parts in the Catia v5 program and then preparation their models for computational fluid dynamics. Numerical simulations were carried out in the Ansys Fluent program, thanks to which several quantities were determined e.g. uniformity index of gas flow through the monolith and coefficient of variation as a measure of mixing degree, which have a significant impact on the design of the mixer and the SCR system.
9
Content available The influence of the injection frequency on the urea selective catalytic reduction systems performance
Rogóż R., Jaworski P., Kapusta Ł. J., Teodorczyk A.
Combustion Engines
|
2017
|
R. 56, nr 3
73--77
EN
This study presents the influence of the UWS injection frequency on a close coupled SCR systems performance. The investigation was performed with the CFD tool AVL Fire. In the paper the analysis of four different UWS injection frequencies in the three different operating points of diesel engine was shown. The assessments of the system performance was referred to the ammonia distribution at catalyst intake and wall film formation inside the investigated geometry, as these are considered as crucial in such a configuration. The results showed that injection frequency affects both factors on different level depending from the flow conditions. In addition, the wall film crystallization risk was discussed basing on the obtained wall film characteristics.
10
Content available Directions in vehicle efficiency and emissions
Johnson T. V., Joshi A.
Combustion Engines
|
2016
|
R. 55, nr 3
3--8
EN
This paper provides a general review of light-duty (LD) and heavy-duty (HD) regulations, engine technology, and key emission control strategies. The US is placing a stronger emphasis on laboratory emissions, and the LD regulations are about an order of magnitude tighter than Euro 6, but Europe is focusing on real-world reductions. The California HD low-NOx regulation is advancing and may be proposed in 2017/18 for implementation in 2023+. The second phase of US HD greenhouse gas regulations propose another 25-30% tightening beyond Phase 1, beginning in 2021. LD and HD engine technology continues showing marked improvements in engine efficiency. LD gasoline concepts are closing the gap with diesel. HD engines are demonstrating more than 50% BTE using methods that can reasonably be commercialized. LD and HD diesel NOx technology trends are also summarized. NOx storage catalysts and SCR combinations are the lead approach to meeting the LD regulations. Numerous advanced NOx technologies are being evaluated and some promise for meeting the California HD low NOx targets. Oxidation catalysts are improved for both diesel and methane oxidation applications. Gasoline particulate filters (GPF) are the lead approach to reducing particles from gasoline direct injection (GDI) engines. They reduce PAH emissions, and catalyzed versions can be designed for low back pressure. Regeneration largely occurs during hot decelerations.
11
Content available Koncepcja systemu redukcji tlenków azotu z ognioszczelnego napędu spalinowego
Kaczmarczyk K.
Maszyny Górnicze
|
2015
|
R. 33, nr 1
23--28
PL
W artykule omówiono koncepcję systemu redukcji tlenków azotu powstałych w wyniku pracy silnika spalinowego z zapłonem samoczynnym, stanowiących szczególne zagrożenie w podziemnych wyrobiskach kopalnianych. Przedstawiono metody konwersji tlenków azotu stosowane z powodzeniem w aplikacjach powierzchniowych. Sformułowano wymagania stawiane napędom pracującym w wyrobiskach zagrożonych wybuchem metanu i pyłu węglowego, uwzględniając potencjalne problemy związane z zastosowaniem metody selektywnej redukcji katalitycznej.
EN
The concept of reduction of nitrogen oxides emitted from diesel engine, which are especially hazardous in underground mine workings, are discussed. Methods of conversion of nitrogen oxides, successfully used in the surface application, are presented. The requirements put to the driving systems operating in mine workings threatened by methane and/or coal dust explosion hazard are formulated considering the method of selective catalytic reduction.
12
Content available Impact of flameproof exhaust system on efficiency of selective catalytic reduction
Kaczmarczyk K., Brzeżański M.
Combustion Engines
|
2015
|
R. 54, nr 4
26--33
EN
Ecological problems associated with operation of diesel engine in underground excavation areas are discussed. Characteristic features of diesel drives operating in excavation zones threatened by explosion hazard, including technical problems with use of selective catalytic reduction, are presented. The results of stationary tests of flameproof diesel drive, in which selective catalytic reduction of nitrogen oxides (NOx) was used, are given.
PL
W artykule omówiono problemy ekologiczne związanie z pracą silnika z zapłonem samoczynnym w wyrobiskach podziemnych. Przedstawiono cechy charakterystyczne spalinowych układów napędowych pracujących w wyrobiskach zagrożonych wybuchem, uwzględniając problemy techniczne związane z zastosowaniem metody selektywnej redukcji katalitycznej. Zaprezentowano wyniki przeprowadzonych badań stanowiskowych ognioszczelnego, spalinowego układu napędowego, w którym zastosowano metodę selektywnej redukcji katalitycznej tlenków azotu.
13
Modelowanie procesów redukcji tlenków azotu w spalinach bloków węglowych
Chmielniak T., Pilarz P.
Rynek Energii
|
2014
|
Nr 5
63--69
PL
W pracy przedstawiono główne metody wtórne odazotowania spalin – selektywną redukcję niekatalityczną (SNCR) oraz selektywną redukcję katalityczną (SCR). W części badawczej przedstawiono wyniki modelowania reaktora SCR z zastosowaniem kodu Ebsilon Professional®. W szczególności przeanalizowano wpływ umiejscowienia reaktora SCR w ciągu technologicznym oczyszczania spalin na proces redukcji tlenków azotu. Obliczeniom poddano trzy lokalizacje instalacji: High-dust SCR, czyli lokowanie katalizatora między podgrzewaczem wody a podgrzewaczem powietrza, spaliny w tym przypadku nie są jeszcze odpylone; Low-dust SCR, polega na odazotowaniu spalin oczyszczonych w elektrofiltrze; Low-dust Tail-end SCR – to instalacja redukująca stężenie NOx ze spalin odpylonych i odsiarczonych. Zbadano również wpływ składu spalin na proces redukcji NOx – wpływ O2 i H2O na efektywność reaktora oraz wpływ stężenia NOx na temperaturę procesu.
EN
This paper presents the main methods of NOx reduction – a selective non-catalytic reduction (SNCR) and a selective catalytic reduction (SCR). The research part include the SCR reactor modeling using the code of Ebsilon Professional®. In particular, analyzed the effect of the location: High-dust SCR means that a catalyst is placed between the feedwater heater and the air preheater, exhaust gases are dusty; Low-dust SCR – flue gases are dust-free; Low-dust Tail-end SCR – this system reduces NOx after the electrostatic precipitation and desulphurization. Examined also the impact of the O2 and H2O on the efficiency SCR and the effect of NOx concentration in flue gases in the process temperature.
14
Selektywna katalityczna redukcja tlenków azotu jako sposób ograniczenia emisji zanieczyszczeń do środowiska
Witowski A., Jasek K.
Elektronika : konstrukcje, technologie, zastosowania
|
2014
|
Vol. 55, nr 7
131-133
PL
W komunikacie przedstawiono zagadnienia związane z problematyką ograniczania emisji tlenków azotu do atmosfery. Przedstawiono argumenty uzasadniające wybór selektywnej redukcji katalitycznej NOx za pomocą amoniaku jako najlepszej dostępnej technologii. Omówiono najnowsze osiągnięcia światowe w stosowaniu tej technologii.
EN
In the communication, the issues connected with limitation of nitrogen oxides emission to the atmosphere are presented. Arguments justifying the choice of selective catalytic NOx reduction by means of an ammonia as the best accessible technology are shown. The latest world achievements in the application of this technology are listed.
15
Content available A comparative analysis of platinum and oxide-based catalytic converters in terms of NOx reduction with ammonia
Kamela W., Kruczyński S.
Silniki Spalinowe
|
2012
|
R. 51, nr 3
55-62
EN
The paper presents a comparison of the catalytic properties of two types of catalytic converters (containing platinum and oxide active coatings) in the aspect of a reduction of nitric oxides with ammonia. The tests were performed for three concentrations of ammonia in the exhaust gases of a diesel engine. The work contains images of the topography of the active surface of the catalytic converters and the results of its physical and chemical analysis. The changes of the conversion rates of the nitric oxides have also been presented in the converter temperature range from 150 to 550 °C along with the results of calculations of the shares of NO2 in NOx for all analyzed concentrations of ammonia in the exhaust gases.
PL
W artykule przedstawiono porównanie właściwości katalitycznych dwóch rodzajów reaktorów katalitycznych z warstwami aktywnymi: platynową i tlenkową w aspekcie redukcji tlenków azotu za pośrednictwem amoniaku. Badania przeprowadzono przy trzech wartościach stężeń amoniaku w gazach spalinowych silnika o zapłonie samoczynnym. Praca zawiera obrazy topografii powierzchni aktywnej reaktorów oraz wyniki jej analizy fizyko-chemicznej. Przedstawiono także zmiany konwersji tlenków azotu w zakresie temperatur pracy reaktorów od 150 do 550 °C oraz wyniki obliczeń udziałów NO2 w NOx dla wszystkich analizowanych wartości stężeń amoniaku w gazach spalinowych.
16
Content available Degrading mechanisms of selective catalytic reduction systems
Herdzik J.
Zeszyty Naukowe / Akademia Morska w Szczecinie
|
2011
|
nr 28 (100) z. 1
27-33
EN
It was presented problems of fulfillment the IMO tier 3 requirements. The proposition of using selective catalytic reduction was very interesting, but provided to many maintenance problems due to the degrading mechanisms of that systems. Some of those mechanisms were presented. It provided to degradation of those systems and worsening their emission reduction possibilities. The certificate of EIAPP may not tell the truth. It needs periodical surveys (minimum one per year) for checking the validity of issued EIAPP certificate. A SCR system would be activated only on restricted areas of environmental emission control due to maintenance costs.
PL
W referacie przedstawiono problemy spełnienia wymagań Międzynarodowej Organizacji Morskiej (IMO) odnośnie wymagań ograniczenia emisji toksycznych składników spalin z silników okrętowych. Propozycja użycia metod selektywnej katalitycznej redukcji (SCR) jest bardzo interesująca, ale prowadzi do wielu problemów w eksploatacji z powodu mechanizmów, które degradują systemy SCR. Niektóre z nich zaprezentowano w referacie. Degradacja systemów SCR powoduje pogorszenie parametrów ich pracy oraz spadek zdolności do zmniejszania emisji szkodliwych substancji w spalinach. Certyfikat EIAPP może nie potwierdzać rzeczywistych osiągów systemów SCR. Wymagać to będzie okresowych przeglądów potwierdzających spełnianie wymagań. Z powodu dużych kosztów eksploatacji systemów SCR będą one wykorzystywane jedynie na obszarach, na których zachodzi konieczność ich użycia, natomiast poza tymi obszarami będą one wyłączane. Pracować będą na systemach omijających systemy SCR.
17
Content available remote Influences of biocomponents (RME) on emissions of a Diesel engine with SCR
Czerwiński J., Stępień Z., Oleksiak S., Otto A.
Nafta-Gaz
|
2011
|
R. 67, nr 3
198-207
EN
SCR (selective catalytic reduction) is regarded as the most efficient deNO[x] - system. In combination with a Diesel particle filter (DPF) it represents a very important step towards zero emission Diesel fleet. The present paper informs about the results obtained with SCR and with blend fuels containing different share of RME (B7, B20, B30 and B100). The investigations were performed according to the procedures of the international network project VERTdePN. Also a combined system (DPF + SCR) was included in the investigations. Beside the legally limited exhaust emission components some non-legislated like NO2, N2O, NH3 and nanoparticles were measured at stationary and dynamic engine operation.
PL
SCR (selective catalytic reduction - selektywna redukcja katalityczna) uznana jest za najskuteczniejszy system ograniczania emisji NO[x]. W połączeniu z filtrem cząstek stałych (DPF), układ stanowi istotny krok w kierunku osiągnięcia zerowej emisji pojazdów z silnikami Diesla. Artykuł prezentuje wyniki badań uzyskane przy zastosowaniu układu SCR i paliw zawierających różny udział RME (B7, B20, B30 i B100). Badania prowadzone były zgodnie z międzynarodowymi procedurami VERTdePN, przy czym obejmowały również system stanowiący połączenie DPF + SCR. W ustalonych i nieustalonych warunkach pracy silnika brano po uwagę zarówno limitowane składniki spalin, jak również niektóre nienormowane, jak NO2, N2O, NH3 i nanocząstki.
18
The life-cycle-assessment of combined bio- and fossil fuel blends with exhaust after-treatment in heavy-duty diesel engines
Gilpin G., Andersen O., Czerwiński J.
Prace Naukowe Instytutu Nafty i Gazu
|
2010
|
nr 172
123-131
EN
The implementation of various international directives for the promotion of biofuels, and new exhaust after-treatment systems aim to reduce the environmental burden of the transport sector. Though what are the real environmental benefits associated with combining blended bio-and fossil diesels with modern exhaust after-treatment systems in heavy transport? This paper disseminates selected parts of a larger EEA funded project known under the acronym BIODEG, and seeks to assess the green-house-gas (GHG) emissions from the inclusion of bio-components into fuel in diesel engines with selective catalytic reduction (SCR) - and diesel particle filter (DPF). Based on existing data, and new step-test exhaust emissions data collected by the Laboratory for Exhaust Emission Control (AFHB) at the University College of Biel Switzerland, life-cycle-assessment (LCA) methodology is applied to calculate the changes in greenhouse gas emissions for heavy-duty diesel engines using rape-methyl-ester (RME) biodiesel and low-sulphur-diesel (LSD) with blending ratios; B0, B7, B20, B30, and B100, and various configurations of SCR and DPF. Preliminary results indicate decreases in life-cycle GHG emissions associated with the inclusion of biodiesel; B100 representing the largest decrease. Though, relative to the individual bio- and fossil diesel blending ratios, the inclusion of SCR and DPF systems lead to increases in life-cycle GHG emissions. This is explained in that, SCR reduces the emission of nitrogen oxides (NOx) and DPF reduces the emission of particles, both compounds without strong green-house effect. There is however GHG emissions in the production and operation phases of SCR and DPF systems. It is concluded that continued research is necessary to substantiate those "hot-spots", or areas of interest identified in this initial scanning LCA.
19
Content available remote Badania katalitycznej redukcji tlenku azotu amoniakiem na karbonizacie z osadów ściekowych
Stelmach S., Figa J., Jastrząb K.
Inżynieria i Ochrona Środowiska
|
2004
|
T. 7, nr 2
185-199
PL
Zaprezentowano rezultaty badań katalitycznej redukcji tlenku azotu amoniakiem na złożu karbonizatu wytworzonego z osadów ściekowych. Mechanicznie odwodniony, przefermentowany osad ściekowy, pochodzący z oczyszczalni ścieków komunalnych, poddano suszeniu na powietrzu do wilgotności ∼ 50%, a następnie wytłoczono z niego cylindryczne granulki. Granulki te, po dosuszeniu na powietrzu do zawartości wilgoci ok. 7%, zostały poddane pirolizie w złożu stałym. Próbkę suchego granulatu o wielkości 600 g umieszczono w retorcie stalowej, a retortę wprowadzono do zimnego pieca, który po włączeniu nagrzewano z szybkością ok. 15°C/min do temperatury 700°C. Piroliza prowadzona była w atmosferze azotu, a próbkę w temperaturze końcowej przetrzymano przez 30 minut. W uzyskanym karbonizacie oznaczono zawartość popiołu i wytrzymałość mechaniczna, a ponadto wykonano dla niego charakterystykę struktury mikroporowatej na podstawie izotermy adsorpcji-desorpcji azotu. Karbonizat ten poddano następnie testowi katalitycznej redukcji tlenku azotu według procedury opracowanej w Katedrze Chemii i Technologii Nieorganicznej Wydziału Chemicznego Politechniki Śląskiej w Gliwicach. Syntetycznie wytworzony gaz o składzie: 82,8% obj. N2, 6,0% obj. O2, 11,0% obj. H2O, 0,1% obj. NO oraz 0,1% obj. NH3 przepuszczano w temperaturze 120°C przez złoże karbonizatu z osadów ściekowych o objętości 300 cm³ z natężeniem przepływu 0,450 Analiza zawartości NO w spalinach opuszczających kolumnę prowadzona była za pomocą automatycznego analizatora URAS 10E. Wyznaczony dla badanego karbonizatu z osadów ściekowych średni stopień redukcji NO, po ustaleniu stanu stacjonarnego, wyniósł 0,114. Uzyskany rezultat porównano z wynikami takich samych badań wykonanych dla komercyjnych koksów aktywnych. Przeprowadzony test wykazał, iż karbonizat z osadów ściekowych charakteryzuje się zdolnością katalitycznej redukcji tlenku azotu tylko nieznacznie niższą od komercyjnych koksów aktywnych. Na tej podstawie można rozważać możliwość wykorzystania karbonizatów z osadów ściekowych w charakterze substytutu komercyjnych koksów aktywnych wykorzystywanych w procesie katalitycznej redukcji NOx za pomocą amoniaku.
EN
Publication presents the testing results of nitrogen oxide (NO) catalytic reduction with ammonia on sewage sludge char bed. The char used at this study has been produced from mechanically dewatered, digested municipal sewage sludge. The sewage sludge has been firstly dried with ambient air up to moisture contents about 50%. Initially dried sewage sludge has been directed to extrusion, to produce cylindrical granules. Raw cylindrical granules of sewage sludge have been further dried with ambient air up to moisture contents about 7%. The 600 g sample of dried, granulated sewage sludge has been used for char production. The sample was placed at the retort made of steel, which was inserted into cold furnace. Then the furnace was turned on and heated with heating rate about 15°C/min, up to final temperature 700°C. Pyrolysis was performed at nitrogen atmosphere and the sample of sewage sludge has been pyrolysed at final temperature by 30 minutes. Obtained char has been analyzed to establish its ash contents and mechanical strength and also its microporous structure has been determined on the basis of nitrogen adsorption-desorption isotherm. The char has been used for testing its catalytic properties in relation to NO reduction with ammonia, according to procedure elaborated at Chemistry and Inorganic Technology Chair of Silesian Technical University. Artificially prepared flue gas with composition: 82.8% N2, 6.0% O2, 11.0% H2O, 0.1% NO and 0.1% NH3 (by volume), has been passed through the 300 cm³ char bed, at temperature 120°C and with flow rate 0.450. The NO contents at the outlet of the column was controlled with automatic analyzer URAS 10E. Average NO catalytic rate determined for tested sewage sludge char was equal 0.114. This result was compared with other results obtained for commercial active cokes. It should be stated that results of NO catalytic reduction with ammonia obtained for sewage sludge char is only a little lower than the same results found for commercial active cokes. Thus, it is possible to assume that sewage sludge chars could be used as a catalyst at industrial catalytic reduction of NOx from flue gases with ammonia.
20
Content available remote Determination of the rate regime of the catalytic process of reducing of nitrogen oxide by means of ammonia on the active coke
Jastrząb K., Szarawara J.
Polish Journal of Chemical Technology
|
2002
|
Vol. 4, nr 3
13-17
EN
The paper presents the results of investigation concerning the determination of the rate of controlling the stage of the process reduction of nitrogen oxide by means of gaseous ammonia on the Polish active coke AKP-5. The influence of the scale factor, the grain diameter and temperature on the degree of the reduction of nitrogen oxide have been investigated. From the obtained results it is clear that the process takes place in the kinetic region and the optimum temperature of this process is 120°C. Apparent activation energy of reduction of nitrogen oxide on active coke has been calculated
first rewind previous Strona / 2 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.