scholarly journals Air pollution by nitrogen oxides in Sarajevo from 2005 to 2010

2013 ◽  
Vol 3 (3) ◽  
pp. 250-254
Author(s):  
Suad Habeš ◽  
Zarema Obradović ◽  
Aida Ridžal ◽  
Asmir Aldžić
Keyword(s):  
Air Pollution ◽  
Nitrogen Oxides ◽  
Positive Result ◽  
Nitrogen Dioxide ◽  
Total Concentration ◽  
Nitrogen Monoxide ◽  
Atmospheric Conditions ◽  
Measuring Point ◽  
Limit Values ◽  
Research Show

Introduction: Air pollution occurs when the concentration of certain substances (pollutants) reaches a size which causes its toxicity, or in other words, begins to cause harm to human health, fl ora and wildlife.Methods: Measurements were performed in the period from 2005 to 2010, at the measuring point Bjelave-Sarajevo by the method of Griess-Saltzmann. It encompasses the following parameters: NO, NO2, NOx, measured concentrations of pollutants in the atmosphere reduced to normal atmospheric conditions of 293 K (Kelvin) and pressure of 101.3 kPa (kilopascal).Results: NO concentration in the period from 2005 to 2008 was above the permitted value, but the results of research in the period between 2009 and 2010, have shown that there was a decrease in NO concentration in the atmosphere. Measurements show that the concentration of this pollutant is currently declining, which is a positive result compared to the pollution of the atmosphere by nitrogen monoxide. Furthermore, the results of the research showed that the concentration of NO2 for the period of 2005 to 2010, is in the limited values, and that has a decreasing trend, which is also a positive result compared to the pollution of the atmosphere by nitrogen dioxide. Related to the total concentration of NOx in the atmosphere, the results of the research show that their representation corresponds to the limit values existing in the Rulebook on limit values for air quality.Conclusion: The results of the research for the pollution of the atmosphere by nitrogen oxides in the investigated area show that the amount of nitrogen oxides in the atmosphere is in constant decline.

scholarly journals Low-Speed Marine Diesel Engine Modeling for NOx Prediction in Exhaust Gases

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4442
Author(s):  
Branko Lalić ◽  
Andrijana Poljak ◽  
Gojmir Radica ◽  
Antonija Mišura
Keyword(s):  
Diesel Engine ◽  
Nitrogen Oxides ◽  
Nitrogen Dioxide ◽  
Nitrogen Oxide ◽  
Fuel Consumption ◽  
Compression Ratio ◽  
Fuel Injection ◽  
Nitrogen Monoxide ◽  
Exhaust Emissions ◽  
Injection Timing

Knowing the process of generating exhaust emissions and the determination of influential parameters are important factors in improving two-stroke slow-speed marine engines, particularly for further reductions in fuel consumption and stringent regulations on the limitation of nitrogen oxide emissions. In this article, a model of a marine low-speed two-stroke diesel engine has been developed. Experimental and numerical analyses of the nitrogen monoxide formations were carried out. When measuring the concentration of nitrogen oxides in the exhaust emissions, the amount of nitrogen dioxide (NO2) is usually measured, because nitrogen monoxide is very unstable, and due to the large amount of oxygen in the exhaust gases, it is rapidly converted into nitrogen dioxide and its amount is included in the total emission of nitrogen oxides. In this paper, the most significant parameters for the formation of nitrogen monoxide have been determined. Model validation was performed based on measured combustion pressures, engine power, and concentrations of nitrogen oxides at 50% and 75% of maximum continuous engine load. The possibilities of fuel consumption optimization and reduction in nitrogen monoxide emissions by correcting the injection timing and changing the compression ratio were examined. An engine model was developed, based on measured combustion pressures and scavenging air flow, to be used on board by marine engineers for rapid analyses and determining changes in the concentration of nitrogen oxides in exhaust emissions. The amount of nitrogen oxide in exhaust emissions is influenced by the relevant features described in this paper: fuel injection timing and engine compression ratio. The presented methodology provides a basis for further research about the simultaneous impact of changing the injection timing and compression ratio, exhaust valve opening and closing times, as well as the impact of multiple fuel injection to reduce consumption and maintain exhaust emissions within the permissible limits.

scholarly journals Mechanism of the oxidation of nitric oxide with oxygen

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Józef Głowiński ◽  
Józef Hoffmann ◽  
Marcin Wilk
Keyword(s):  
Nitric Oxide ◽  
Nitrogen Oxides ◽  
Nitrogen Dioxide ◽  
Gas Phase ◽  
Oxidation Reaction ◽  
Nitrogen Monoxide ◽  
Fast Reactions

Abstract Very fast reactions of forming higher nitrogen oxides set out an equilibrium framework for the course of the reaction of nitrogen monoxide oxidation. The slow course of reaction of nitrogen monoxide with oxygen permanently violates the created equilibria. In particular, the equilibrium of the oxidation reaction of nitrogen monoxide with nitrogen dioxide. The contribution of this reaction to the transformation of nitrogen monoxide in the conditions of nitrogen trioxide removal from the gas phase was estimated.

Intercomparison of nitrogen monoxide and nitrogen dioxide measurements in the atmosphere simulation chamber SAPHIR during the MetNO2 campaign

2020 ◽  
Author(s):  
Robert Wegener ◽  
Keyword(s):  
Nitrogen Oxides ◽  
Nitrogen Dioxide ◽  
Gas Phase ◽  
Nitrogen Monoxide ◽  
Ambient Air ◽  
Alkyl Nitrates ◽  
Dinitrogen Pentoxide ◽  
Laser Absorption ◽  
Calibration Techniques ◽  
Atmosphere Simulation Chamber

<p>Nitrogen dioxide (NO<sub>2</sub>) and nitrogen monoxide (NO) govern the photochemical processes in the troposphere. Although nitrogen oxides have been measured for decades, their quantification remains challenging. The MetNO2 (Metrology for Nitrogen Dioxide) project of the European Metrology Programme for Innovation and Research (EMPIR) aims to improve the accuracy of NO<sub>2</sub> measurements.</p><p>In total 15 instruments were intercompared at the World Calibration Centre for nitrogen oxides (WCC-NOx) in Jülich in autumn 2019 within the project. In addition to chemiluminescence detectors (CLD), the instruments encompassed Quantum Cascade Laser Absorption Spectrometers (QCLAS), Iterative CAvity-enhanced Differential optical absorption spectrometers (ICAD) and Cavity Attenuated Phase Shift (CAPS) spectrometers.</p><p>During the campaign, air from a gas phase titration unit, air from the environmental chamber SAPHIR or outside air was provided to the instruments via a common inlet line. The participants calibrated their instruments prior and after the campaign with their own calibration procedures. During the campaign, the common inlet line was used for daily calibration to compare standards, calibration techniques and sensitivity drifts of the instruments. NO<sub>2</sub> for calibration was provided either by gas phase titration from NO, from permeation tubes or from gas mixtures produced within the MetNO2 project.</p><p>It was observed that measurements by chemiluminescence or CAPS instruments are prone to interferences from humidity and ozone. However, in most cases data can be corrected. Alkyl nitrates and reactive alkenes were also observed to cause interferences in some instruments, while isobutyl nitrite was found to be photolyzed by photolytic converters.</p><p>Finally, measurements in ambient air were compared. The nitrogen oxide observations were accompanied with measurements of hydroxyl radical (OH) reactivity and reactive nitrogen species as nitrous acid (HONO), dinitrogen pentoxide (N<sub>2</sub>O<sub>5</sub>), and chloryl nitrate (ClNO<sub>2</sub>). Detailed results of the intercomparison will be presented.</p>

Reactivity of Nitrogen Oxides Towards Sodium Carbonate and Hydrogencarbonate Based Solid Sorbents

1996 ◽  
Vol 61 (12) ◽  
pp. 1709-1714
Author(s):  
Erich Lippert ◽  
Pavel Bach ◽  
Květoslava Stejskalová ◽  
Emerich Erdös ◽  
Karel Mocek
Keyword(s):  
Carbon Dioxide ◽  
Water Vapor ◽  
Nitrogen Oxides ◽  
Nitrogen Dioxide ◽  
Sodium Carbonate ◽  
Nitrogen Monoxide ◽  
Reaction Products ◽  
Solid Sorbents ◽  
Lower Reactivity ◽  
Technological Interest

The reactivity of nitrogen oxides towards sodium carbonate and hydrogencarbonate based solids was measured within a range of variables which is of technological interest. The reactivity is significant at lower temperatures only and is not affected by the presence of carbon dioxide or oxygen. Water vapor acts as a catalyst. Nitrogen dioxide is more reactive than nitrogen monoxide. The reactivity of the solid depends substantially on its origin and way of preparation. As compared with SO2 or HCl, nitrogen oxides exhibit a lower reactivity, presumably because the solid is blocked by the reaction products.

Equilibria of the Reactions Between Nitrogen Oxides and the Sodium Carbonate

1994 ◽  
Vol 59 (3) ◽  
pp. 517-527
Author(s):  
Emerich Erdös ◽  
Karel Mocek
Keyword(s):  
Carbon Dioxide ◽  
Nitrogen Oxides ◽  
Nitrogen Dioxide ◽  
Sodium Carbonate ◽  
Nitrogen Monoxide ◽  
Point Of View ◽  
General Analysis ◽  
Gaseous Nitrogen ◽  
Chemical Equilibria ◽  
Partial Pressures

A general analysis of chemical equilibria in a system consisting of the gaseous nitrogen monoxide, nitrogen dioxide, carbon dioxide, oxygen and of the solid sodium carbonate is carried out with respect to the equilibrium partial pressures of nitrogen oxides. The pertaining equations are derived for three regions of existence of the above system. The results are represented graphically and discussed from the point of view of removing the nitrogen oxides from the waste gases.

VALORIZATION OF THE URBAN ENVIRONMENT OF SOUTH SERBIA FROM THE AIR QUALITY ASPECT

2018 ◽  
Vol 28 (4) ◽  
pp. 1329-1333
Author(s):  
Miodrag Šmelcerović
Keyword(s):  
Air Pollution ◽  
Air Quality ◽  
Urban Environment ◽  
Pollution Sources ◽  
Anthropogenic Sources ◽  
Anthropogenic Factors ◽  
Limit Values ◽  
Cause And Effect ◽  
Sources Of Pollution

The protection of the environment and people’s health from negative influences of the pollution of air as a medium of the environment requires constant observing of the air quality in accordance with international standards, the analysis of emission and imission of polluting matters in the air, and their connection with the sources of pollution. Having in mind the series of laws and delegated legislations which define the field of air pollution, it is necessary to closely observe these long-term processes, discovering cause-and-effect relationships between the activities of anthropogenic sources of emission of polluting matters and the level of air degradation. The relevant evaluation of the air quality of a certain area can be conducted if the level of concentration of polluting matters characteristic for the pollution sources of this area is observed in a longer period of time. The data obtained by the observation of the air pollution are the basis for creation of the recovery program of a certain area. Vranje is a town in South Serbia where there is a bigger number of anthropogenic pollution sources that can significantly diminish the air quality. The cause-and-effect relationship of the anthropogenic sources of pollution is conducted related to the analysis of systematized data which are in the relevant data base of the authorized institution The Institute of Public Health Vranje, for the time period between the year of 2012. and 2017. By the analysis of data of imission concentrations of typical polluting matters, the dominant polluting matters were determined on the territory of the town of Vranje, the ones that are the causers of the biggest air pollution and the risk for people’s health. Analysis of the concentration of soot, sulfur dioxide and nitrogen oxides indicates their presence in the air of Vranje town area in concentrations that do not exceed the permitted limit values annually. The greatest pollution is caused by the soot content in the air, especially in the winter period when the highest number of days with the values above the limit was registered. By perceiving the influence of natural and anthropogenic factors, it is clear that the concentration of polluting matters can be decreased only by establishing control over anthropogenic sources of pollution, and thus it can be contributed to the improvement of the air quality of this urban environment.

Environmental and Hygienic Assessment of Ambient Air Pollution in Oil-Producing and Oil-Refining Areas of the Republic of Bashkortostan and Population Health Status

2020 ◽  
pp. 26-32
Author(s):  
Z.B. Baktybaeva ◽  
R.A. Suleymanov ◽  
T.K. Valeev ◽  
N.R. Rahmatullin ◽  
E.G. Stepanov ◽  
...  
Keyword(s):  
Air Pollution ◽  
Carbon Monoxide ◽  
Health Status ◽  
Nitrogen Dioxide ◽  
Population Health ◽  
Respiratory Diseases ◽  
Ambient Air ◽  
Oil Refining ◽  
Disease Rates ◽  
Total Suspended Particles

Introduction. High density of oil-producing and refining facilities in certain areas of Bashkortostan significantly affects the environment including ambient air quality in residential areas. Materials and methods. We analyzed concentrations of airborne toxicants (sulfur and nitrogen oxides, nitrogen and carbon oxides, hydrogen sulfide, ammonia, xylenes, toluene, phenol and total suspended particles) and population health status in the cities of Ufa, Sterlitamak, Salavat, Blagoveshchensk, and the Tuymazinsky District in 2007–2016. Pearson's correlation coefficients (r) were used to establish possible relationships between medico-demographic indicators and air pollution. Results. Republican fuel and energy enterprises contributed the most to local air pollution levels. Gross emissions from such enterprises as Bashneft-Ufaneftekhim and Bashneft-Navoil reached 43.69–49.77 thousand tons of pollutants per year. The levels of some air pollutants exceeded their maximum permissible concentrations. Elevated concentrations of ammonia, total suspended particles, nitrogen dioxide, and carbon monoxide were registered most frequently. High rates of congenital abnormalities, respiratory diseases in infants (aged 0-1), general mortality and morbidity of the population were observed in some oil-producing and refining areas. The correlation analysis proved the relationship between the concentration of carbon monoxide and general disease rates in adults based on hospital admissions (r = 0.898), general incidence rates in children (r = 0.957), and blood disease rates in infants (r = 0.821). Respiratory diseases in children correlated with nitrogen dioxide emission levels (r = 0.899). Conclusions. Further development of oil-producing, petrochemical and oil-refining industries should be carried out taking into account socio-economic living conditions of the population.

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