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Potencjał materiałów pochodzenia naturalnego zawierających mangan w katalitycznym oczyszczaniu gazów odlotowych z instalacji kwasu azotowego

Inger Marek, Rajewski Jakub, Kowalik Wojciech, Hubicki Zbigniew, Bąk Justyna, Wójcik Dominika

Przemysł Chemiczny

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2023

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T. 102, nr 12

1334--1341

PL

W pracy zbadano możliwość zastosowania dwóch naturalnych materiałów zawierających tlenek manganu, Pyrolox® iPurolite MZ-10® , jako układu wyjściowego przy opracowaniu nowego katalizatora wtechnologii oczyszczania z N₂O lub NOₓ strumienia gazów resztkowych z instalacji kwasu azotowego. Obie badane próbki poddano charakterystyce fizyczno-chemicznej. Wykonane pomiary wykazały, że jedynie Pyrolox® wykazuje aktywność w reakcji rozkładu N₂O. Uzyskano konwersję N₂O wynoszącą 31 i 70% wtemp. odpowiednio 480 i 495°C. Po dodaniu do strumienia gazów resztkowych amoniaku stwierdzono aktywność obu badanych materiałów w reakcji redukcji NOₓ. Wtym przypadku stwierdzono również znaczące zwiększenie stężenia N₂O w strumieniu gazów poreakcyjnych, co powoduje znikomą przydatność tych materiałów jako katalizatorów selektywnej redukcji NOₓ.

EN

A lab. flow reactor with a fixed bed of catalyst (Pyrolox® or Purolite MZ-10®) was fed with a stream of tail gases from the HNO₃ plant. The process of N₂O decompn. and NOₓ redn. was studied at temp. of 249-458°C. Only Pyrolox® was active in the N₂O decompn. reaction with conversions of 31 and 70% at 480 and 495°C, resp. After adding NH₃ to the tail gas stream, both tested materials were found to be active in the NOₓ redn. reaction. However, in this process, a significant increase in the N₂O concn. was found in the post-reaction gas stream, which makes these materials of little use as a catalyst for selective NOₓ redn. Pyrolox® and Purolite MZ-10® were analyzed for the sp. surface area, pore size as well as chem. compn.

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Application of Laboratory Tests in Numerical Analysis for Exhaust Emissions in Business Jet Engines

Kozakiewicz Adam, Kołodziejska Aleksandra, Kieszek Rafał

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 4

21--35

EN

This article deals with the exhaust emissions from aircraft turbine engines, which is related to the rapidly growing market for this type of aircraft and its contribution to toxic emissions. The test carried out was done on a business jet turbine engine exhaust pollutants. The test object was the DGEN 380 engine. In order to determine the toxic composition of the exhaust gas as a function of the engine's operating range, an experiment related to the actual engine was conducted in the first stage. The test performed on the static thrust stand of the DGEN 380 turbine engine provided the necessary data on the parameters of the working medium for further research. The actual rotational characteristics of the engine were obtained. It was also determined numerically using GasTurb software. A high correspondence between experimental and calculated parameters was obtained, which gave the possibility of using them in further analyses of the exhaust gas pollutants of the studied engine. The correspondence of the results showed the correctness of the computational model built, thus predestining it for use in further analysis. This paper presents a model of the reverse-flow combustor made for numerical thermal-fluid studies. The thermal-fluid analysis of the model was performed in the ANSYS Fluent environment. The calculations were performed for three shaft speed. The numerical analysis provided information on changes in pollutant components of the exhaust gas of the DGEN 380 aircraft turbine engine as a function of changes in the shaft speed range. The results showed that the levels of nitrogen oxides depend greatly on shaft speed. The model built and the numerical analyses conducted also provided information about the zones inside of liner casing that affect significantly the amount of pollutant compounds obtained, which can then be used in the work on improving the design in terms of reducing the engine exhaust pollutants.

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The comparative analysis of catalytic properties of Group 11 elements in NOx reduction by hydrocarbons in the presence of oxygen

Kruczyński Stanisław W., Orliński Piotr, Ślęzak Marcin

Eksploatacja i Niezawodność

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2022

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Vol. 24, no. 1

170--176

EN

NOx emission reduction in diesel engines can be achieved by using catalytic reactors reducing nitrogen oxides, including NH3-SCR and possibly also HC-SCR reactors. Reactors using ammonia achieve large conversion rates but cause a lot of operational problems. For this reason, the interest in reactors using hydrocarbons and their derivatives to reduce NOx has increased. Such reactors are the ones using metals from Group 11 (coinage metals) such as Cu, Ag and Au placed on an Al2O3-SiO2 carrier as active materials. The article characterizes the porosity and acidity of the carrier surface. Conversion of NO2, NO and propene as well as the formation of CO and N2O depending on the temperature at constant dosing of propene on a carrier covered with Cu, Ag and Au with a metal content of 4 g/dm3 were evaluated. The results of the tests showed that the tested Group 11 elements can be the basis for further experiments related to the development of this exhaust fumes cleaning technology for diesel engines.

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Experimental results and minimizing NOX emissions’ analysis from the fluidized bed boiler of type OE700

Ziaja Jolanta, Lichota Janusz

Rynek Energii

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2021

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Nr 6

76--89

EN

The article shows a solution to the problem of reducing nitrogen oxide (NOx) emissions to a concentration of 150 mg/m3, on an example of 261 MWe fluidized bed boiler. It is a lignite-fired boiler. To reduce emissions a selective noncatalytic reduction (SNCR) method was used. Among the others optimization of urea injection nozzles’ position through a series of on-site experiments after previous 3D simulations were carried out. The result of the experiments was to reduce the number of injection nozzles, determine their optimal position and determine urea streams and injection angles. Major and interesting findings and actual contribution of this manuscript to the field is: dependence of nitrogen oxide NOx emissions on about 100 different variables determined by the correlation with nitrogen oxide emissions’ analysis. Individual variables such as temperature, O2 in exhaust gases, air-to-coal ratio, mass flow and pressure of urea are not sufficient to describe mathematically the NOx capture process. Technical novelty of the SNCR system consists of the urea stream control systems, which can maintain either a constant urea concentration or a constant urea pressure. The NOx reduction systems used so far do not use pressure control. It is experimentally shown that reaction between NOx and reagent can be achieved at lower temperature equal to 700°C in some parts of boiler, which is lower temperature than reported in the literature.

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The new meaning of solid fuels from lignocellulosic biomass used in low-emission automatic pellet boilers

Mirowski Tomasz, Jach-Nocoń Marta, Jelonek Iwona, Nocoń Adam

Polityka Energetyczna

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2020

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T. 23, z. 1

75--86

EN

The energy obtained from biomass in the global balance of energy carriers is the largest source among all RES. It should be borne in mind that the share of biomass as an energy carrier in the total balance is as much as 14%. The basic sources of renewable energy used in Poland are the wind power industry and biomass. Organic chemical compounds are the source of chemical energy for biomass. The biomass can be used in a solid form (wood, straw) or after being converted to liquid (alcohol, bio-oil) or gas (biogas) form. Pellets, meaning, the type of fuel of natural origin created from biomass compressed under high pressure without the participation of any chemical adhesive substances are recognized as the most common and available grades of biomass. Wood pellets manufactured from sawdust, shaving, or woodchips are the most popular type of pellets on the market. Fuel created in the form of granules is very dense and can be manufactured with low humidity content, which translates into an exceptionally high burn efficiency. The authors of this article burned agro pellets from Miscanthus giganteus without additives and with solid catalyst and conducted a series of tests that determine the impact of boiler settings (blast power, time of feeding, chimney draft) on the process of burning fuel in real conditions. A solid catalyst was used to improve combustion conditions in one of the fuels. The catalyst burns carbon monoxide and reduces nitrogen oxides. The results in the form of observation of selected parameters are summarized in the table.

PL

Energia uzyskiwana z biomasy w globalnym bilansie nośników energii jest największym źródłem spośród wszystkich OZE. Należy pamiętać, że udział biomasy jako nośnika energii w całkowitym bilansie wynosi aż 14%. Podstawowymi źródłami energii odnawialnej wykorzystywanymi w Polsce są energetyka wiatrowa i biomasa. Organiczne związki chemiczne są źródłem energii chemicznej dla biomasy. Tę z kolei można wykorzystać w postaci stałej (drewno, słoma) lub po przekształceniu w płynną (bioetanol, bioolej) lub gazową (biogaz). Pellety, czyli rodzaj paliwa pochodzenia naturalnego wytworzonego z biomasy sprasowanej pod wysokim ciśnieniem bez udziału jakichkolwiek chemicznych substancji klejących, są uznawane za najbardziej powszechne i dostępne rodzaje paliwa z biomasy. Pelety drzewne wytwarzane z trocin, wiórów lub zrębki są najpopularniejszym rodzajem peletów na rynku. Paliwo wytwarzane w postaci granulatu (granulek) jest bardzo gęste i może być wytwarzane przy niskiej wilgotności, co przekłada się na wyjątkowo wysoką efektywność spalania. Autorzy tego artykułu wykonali serię testów spalania peletów agro z trawy Miscanthus giganteus bez dodatków uszlachetniających oraz z katalizatorem stałym. Badania miały na celu określenie wpływu ustawień kotła (moc dmuchawy, czas podawania, ciąg kominowy) na proces spalania paliwa w rzeczywistych warunkach. Stały katalizator zastosowano do poprawy warunków spalania w jednym z paliw. Katalizator pozwala dopalić tlenek węgla i redukuje tlenki azotu. Wyniki w postaci obserwacji wybranych parametrów zestawiono w tabeli.

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Numerical investigation of heat transfer in fuel-water emulsion droplet

Rodzewicz R., Gieras M.

Archivum Combustionis

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2018

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Vol. 38 nr 1

1--10

EN

This paper aims to iiwestigate heat flow in fuel/water emulsion droplet using ANSYS Fluent code. A model was tested under different boundary conditions including various flow temperatures, velocities, droplet sizes, water contents, etc. The rate of a temperaturę increment was monitored inside dispersed phase droplets. The obtained results were compared to find out in which case boiling point was reached in all water droplets simultaneously. Such a temperaturę distribution is suspected to be the main condition for microexplosion occurrence. However, this should be confirmed experimentally. Simulations show that a higher temperaturę and a smaller droplet diameter may promote microexplosion. Also it appears that there exists an optimal flow velocity, when the difference of time of reaching boiling point for every water droplet is the smallest. The minor, but a very interesting observation concerns a negligible impact of water presence on heat distribution. It has been shown that treating an emulsion droplet as a continuum with an averaged specific heat of water and oil may result in an error less than 1%. It is an useful conclusion that enables the analytical approach to the problem. The obtained results provide a solid basis for further experimental research.

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Effect of dE-NOx techniques employed in thermal power plants on fly ash properties

Łaskawiec K., Gębarowski P., Kramek-Romanowska K.

Acta Energetica

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2016

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nr 4

58--63

EN

Coal fly ash, a by-product of coal combustion in thermal power plants, is one of the most complex and abundant of anthropogenic materials. For several years, fly ash has predominantly been used as a substitute for material in the construction industry, especially either as a raw material or as an additive in the cement industry all over the world. The wide implementation of low-NOx combustion technologies in pulverized coal combustion can lead to changes in fly ash properties, which may negatively affect its applicability to the production of building materials. In the study, brief characterization of current deNOx techniques, applied in power plants for efficient NOx reduction, is presented and possible alterations in fly ash utilization in concrete production are discussed.

PL

Popiół lotny z węgla, uboczny produkt spalania węgla w elektrowniach cieplnych, jest jednym z najbardziej złożonych i obfitych materiałów antropogenicznych. Od kilku lat popiół lotny jest stosowany głównie jako substytut materiału w przemyśle budowlanym, zwłaszcza jako surowiec lub domieszka w przemyśle cementowym na całym świecie. Powszechne wdrożenie technologii spalania pyłu węglowego przy niskiej emisji NOx może prowadzić do zmian właściwości popiołów lotnych, co może zaszkodzić ich przydatności do produkcji materiałów budowlanych. W pracy tej przedstawiono krótką charakterystykę współczesnych technik stosowanych w elektrowniach do skutecznej redukcji NOx oraz omówiono możliwe zmiany w wykorzystaniu lotnego popiołu w produkcji betonu.

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Porównanie właściwości koksów aktywnych stosowanych w przemysłowych instalacjach oczyszczania gazów spalinowych

Jastrząb K., Zin M.

Inżynieria i Ochrona Środowiska

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2000

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T. 3, nr 3/4

377-388

PL

Przedstawiono porównanie właściwości fizykochemicznych kilku koksów aktywnych różnych producentów, stosowanych w przemysłowych instalacjach oczyszczania gazów spalinowych. Opracowano metodykę testowania pojemności sorpcyjnej SO2 i aktywności katalitycznej redukcji NOx. Wykazano, że właściwości polskich koksów aktywnych są porównywalne z analogicznymi produktami zagranicznymi.

EN

The comparison of some properties of several active cokes used in industrial plants for the purification of combustion gases has been presented in the paper. The method of testing of SO2 sorption capacity and NOx catalytical reduction activity has been developed. It was indicated that the properties of Polish active cokes are comparable with analogous foreign products.