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Saving Energy and Reducing Polycyclic Aromatic Hydrocarbons Emissions from a Heavy-Duty Diesel Engine by H2/O2 Addition to the Combustion ChamberHuang, Yi-Sheng 23 June 2011 (has links)
The emission of polycyclic aromatic hydrocarbons (PAHs) from the diesel engine on a dynamometer by mixing ratio of the fuel (H2/O2 /diesel) was investigated. The engine was operated at a one load steady-state condition of 1,600 rpm with torque and power outputs of 145 Nm and 24.5 kW. In this condition, the measurement of the mixing ratio of the
fuel (H2/O2 /diesel) was first recorded without any induction of H2/O2 mixture (Base) into the engine. Then, seven flow rate levels of H2/O2 mixture were used by 10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min, and 70 L/min, respectively.
The concentrations of total PAHs were 106.58, 101.89, 95.30, 90.70, 85.98, 82.35, 72.38, and 67.30 £gg/m3, respectively for Base (0 L/min), 10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min, and 70 L/min of H2/O2 mixture. The emission factor of total PAHs were 6.00, 5.73, 5.36, 4.99, 4.84, 4.50, 4.07, and 3.78 mg/bhp-hr, respectively for Base (0 L/min), 10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min, and 70 L/min of H2/O2 mixture. The removal rate of total PAHs were 4.4%, 10.6%, 14.9%, 19.3%, 22.7%, 32.1%, and 36.9%, respectively for 10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min, and 70 L/min of H2/O2 mixture. This result showed using H2/O2 mixture significantly reduced emissions of PAHs.
As the regulated harmful matters, using H2/O2 mixture, CO¡BCO2¡BTHC and PM decreased, whereas the NOx emission increased.
The energy saving of the fuels (H2/O2 /diesel), the total oil equivalents combined by fuel consumption of diesel engine and electricity consumption of H2/O2 generator, were 2.42, 2.49, 2.50, 2.48, 2.51, 2.35, 2.18, and 2.17 for Base (0 L/min), 10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min, and 70 L/min of H2/O2 mixture. The result showed that reduced saving energy of the fuel (H2/O2 /diesel) by 3.2% for 50 L/min, 9.8% for 60 L/min, and 10.4% for 70 L/min,
respectively.
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Saving Energy and Reducing Carbonyl Compounds Emissions using H2/O2 Alternative Fuel on a Heavy-Duty Diesel EngineWang, Ying-Lan 23 June 2011 (has links)
This research carries out all tests in diesel engine takes neat diesel and hydrogen+oxygen (H2/O2) which is used as an additive (H2/O2 mixture: 10 to 70 L/min, interval 10 L/min) in a stable state condition (engine was operated at one load steady-state condition of 1600 rpm with torque and power outputs of 145 Nm and 24.5 kW, respectively). Characteristics of carbonyls emissions from H2/O2 as an additive were investigated in a HDDE (heavy-duty diesel engine) and compared with those from neat diesel, contains the concentration, emission factor and elimination efficiency, whole of change tendency in order to help the understanding of diesel engine pollutant emissions, and appraises energy conservation of benefit which add to H2/O2.
The regulated pollutants emission, using H2/O2 mixture (10 to 70 L/min), THC, CO, CO2 and PM emission all increased while H2/O2 showed signs of decrease; on the contrary, NOx emission increased while H2/O2 increased.
Regarding Carbonyls emissions, the total carbonyls concentration of diesel engine take neat diesel was 3218.02 £gg/m3 and the emission factors for diesel engine take neat diesel were 180.882 mg/bhp-hr and 788.061 mg/L-fuel, respectively. When H2/O2 mixture was added, total carbonyls concentration of 3068.28, 3006.42, 2823.10, 2707.06, 2500.54, 2216.87 and 2178.27 mg/m3 were 10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min and 70 L/min, respectively. The emission factor may be divided into mg/bhp-hr and mg/L-fuel; the emission factor of total carbonyls were 231.36¡B226.18¡B211.41¡B203.14¡B186.98¡B167.17 and 164.23 mg/bhp-hr, respectively; the emission factor of total carbonyls were 764.95¡B755.15¡B719.97¡B707.36¡B704.40¡B694.27 and 690.47 mg/L-fuel, respectively. Increases in H2/O2 can reduce total carbonyls emissions with an eliminating efficiency rate of 4.7, 6.6, 12.3, 15.9, 22.3, 31.1 and 32.3%, respectively.
Energy conservation of appraisal increase H2/O2, diesel equivalent sun of fuel consumption of diesel engine and electricity consumption of H2/O2 generator, namely can distinguish that its energy consumption, whole consumes were 2.51, 2.58, 2.59, 2.57, 2.60, 2.43, 2.26 and 2.25, respectively. When compared with neat diesel, result showed in H2/O2 from 10 L/min to 40 L/min, diesel equivalent increased while H2/O2 showed increase; but in H2/O2 from 50 L/min to 70 L/min reflected in a gradual decrease in diesel equivalent, indicating that increases in H2/O2 can effectively achieve energy conservation. The result showed that energy conservation was 3.4%, 10.0% and 10.6% for 50 L/min, 60 L/min and 70 L/min, respectively. The result indicated H2/O2 was 60 L/min when energy conservation benefit was most remarkable, therefore this had the best energy conservation.
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SO2 and O2 separation by using ionic liquid absorption / S.L. RabieRabie, Samuel Liversage January 2012 (has links)
In order to reduce the amount of pollution that is generated by burning fossil fuels alternative
energy sources should be explored. Hydrogen has been identified as the most promising
replacement for fossil fuels and can be produced by using the Hybrid Sulphur (HyS) cycle.
Currently the SO2/O2 separation step in the HyS process has a large amount of knock out
drums. The aim of this study was to investigate new technology to separate the SO2 and O2.
The technology that was identified and investigated was to separate the SO2 and O2 by
absorbing the SO2 into an ionic liquid.
In this study the maximum absorption, absorption rate and desorption rate of SO2 from the
ionic liquid [BMIm][MeSO4] with purities of 95% and 98% was investigated. These ionic liquid
properties were investigated for pure O2 at pressures ranging from 1.5 to 9 bar(a) and for
pure SO2 at pressures from 1.5 to 3 bar(a) at ambient temperature. Experiments were also
carried out where the composition of the feed-stream to the ionic liquid was varied with
compositions of 0, 25, 50, 75 and 100 mol% SO2 with O2 as the balance. For each of these
compositions the temperature of the ionic liquid was changed from 30oC to 60oC, in
increments of 10oC.
The absorption rate of SO2 in the ionic liquid increased when the mole percentage SO2 in the
feed stream was increased. When the temperature of the ionic liquid was decreased the
maximum amount of SO2 that the ionic liquid absorbed increased dramatically. However, the
absorption rate was not influenced by a change in the absorption temperature.
The experimental results for the maximum SO2 absorption were modelled with the Langmuir
absorption model. The model fitted the data well, with an average standard deviation of
17.07% over all the experiments. In order to determine if the absorption reaction was
endothermic or exothermic the Clausius-Clapeyron equation was used to calculate the heat
of desorption for the desorption step. The heat of desorption data indicated that the
desorption of SO2 from this ionic liquid was an endothermic reaction because the heat of
desorption values was positive. Therefore the absorption reaction was exothermic.
From the pressure-change experiments the results showed that the mole percentage of O2
gas that was absorbed into the ionic liquid was independent of the pressure of the O2 feed.On the other hand, there was a clear correlation between the mole percentage SO2 that was
absorbed into the ionic liquid and the feed pressure of the SO2. When the feed pressure of
the SO2 was increased the amount of SO2 absorbed also increased, this trend was
explained with Fick’s law.
In the study the effect of the ionic liquid purity on the SO2 absorption capacity was
investigated. The experimental results for the pressure experiments showed that the 95%
and 98% pure ionic liquid absorbed about the same amount of SO2. During the temperature
experiments the 95% pure ionic liquid absorbed more SO2 than the 98% pure ionic liquid for
all but two of the experiments. However the 95% pure ionic liquid also absorbed small
amounts of O2 at 30 and 40oC which indicated that the 95% pure ionic liquid had a lower
selectivity than the 98% pure ionic liquid. Therefore, the 95% pure ionic liquid had better SO2
absorption capabilities than the 98% pure ionic liquid.
These result showed that the 98% pure ionic liquid did not absorb more SO2 than the 95%
pure ionic liquid, but it did, however, show that the 98% pure ionic liquid had a better
selectivity towards the SO2. Hence, it can be concluded that even with the O2 that is
absorbed it would be economically more advantageous to use the less expensive 95% pure
ionic liquid rather than the expensive 98% pure ionic liquid, because the O2 would not
influence the performance of the process negatively in such low quantities. / Thesis (MIng (Chemical Engineering))--North-West University, Potchefstroom Campus, 2013
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SO2 and O2 separation by using ionic liquid absorption / S.L. RabieRabie, Samuel Liversage January 2012 (has links)
In order to reduce the amount of pollution that is generated by burning fossil fuels alternative
energy sources should be explored. Hydrogen has been identified as the most promising
replacement for fossil fuels and can be produced by using the Hybrid Sulphur (HyS) cycle.
Currently the SO2/O2 separation step in the HyS process has a large amount of knock out
drums. The aim of this study was to investigate new technology to separate the SO2 and O2.
The technology that was identified and investigated was to separate the SO2 and O2 by
absorbing the SO2 into an ionic liquid.
In this study the maximum absorption, absorption rate and desorption rate of SO2 from the
ionic liquid [BMIm][MeSO4] with purities of 95% and 98% was investigated. These ionic liquid
properties were investigated for pure O2 at pressures ranging from 1.5 to 9 bar(a) and for
pure SO2 at pressures from 1.5 to 3 bar(a) at ambient temperature. Experiments were also
carried out where the composition of the feed-stream to the ionic liquid was varied with
compositions of 0, 25, 50, 75 and 100 mol% SO2 with O2 as the balance. For each of these
compositions the temperature of the ionic liquid was changed from 30oC to 60oC, in
increments of 10oC.
The absorption rate of SO2 in the ionic liquid increased when the mole percentage SO2 in the
feed stream was increased. When the temperature of the ionic liquid was decreased the
maximum amount of SO2 that the ionic liquid absorbed increased dramatically. However, the
absorption rate was not influenced by a change in the absorption temperature.
The experimental results for the maximum SO2 absorption were modelled with the Langmuir
absorption model. The model fitted the data well, with an average standard deviation of
17.07% over all the experiments. In order to determine if the absorption reaction was
endothermic or exothermic the Clausius-Clapeyron equation was used to calculate the heat
of desorption for the desorption step. The heat of desorption data indicated that the
desorption of SO2 from this ionic liquid was an endothermic reaction because the heat of
desorption values was positive. Therefore the absorption reaction was exothermic.
From the pressure-change experiments the results showed that the mole percentage of O2
gas that was absorbed into the ionic liquid was independent of the pressure of the O2 feed.On the other hand, there was a clear correlation between the mole percentage SO2 that was
absorbed into the ionic liquid and the feed pressure of the SO2. When the feed pressure of
the SO2 was increased the amount of SO2 absorbed also increased, this trend was
explained with Fick’s law.
In the study the effect of the ionic liquid purity on the SO2 absorption capacity was
investigated. The experimental results for the pressure experiments showed that the 95%
and 98% pure ionic liquid absorbed about the same amount of SO2. During the temperature
experiments the 95% pure ionic liquid absorbed more SO2 than the 98% pure ionic liquid for
all but two of the experiments. However the 95% pure ionic liquid also absorbed small
amounts of O2 at 30 and 40oC which indicated that the 95% pure ionic liquid had a lower
selectivity than the 98% pure ionic liquid. Therefore, the 95% pure ionic liquid had better SO2
absorption capabilities than the 98% pure ionic liquid.
These result showed that the 98% pure ionic liquid did not absorb more SO2 than the 95%
pure ionic liquid, but it did, however, show that the 98% pure ionic liquid had a better
selectivity towards the SO2. Hence, it can be concluded that even with the O2 that is
absorbed it would be economically more advantageous to use the less expensive 95% pure
ionic liquid rather than the expensive 98% pure ionic liquid, because the O2 would not
influence the performance of the process negatively in such low quantities. / Thesis (MIng (Chemical Engineering))--North-West University, Potchefstroom Campus, 2013
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Dynamique des plasmas radio-fréquence à couplage inductif en gaz halogénés simples / Dynamic of radio-frequency inductively-coupled plasmas in simple halogen gasesFoucher, Mickaël 24 October 2016 (has links)
Les plasmas radio-fréquences à couplage inductif en gaz halogénés simples (cl2/hbr/o2) sont fortement utilisés dans l'industrie des semi-conducteurs. Cependant, notre connaissance des processus réactionnels de ces plasmas est encore très partielle. De nombreux travaux de simulations (fluides, particulaires...), visant à améliorer celle-ci, ont été produits ces dernières décennies. Toutefois, trop peu de résultats expérimentaux sont disponibles dans la littérature afin de valider ou améliorer ces simulations. L'objectif de cette thèse est alors de produire un ensemble complet de résultats experimentaux. Nous nous focalisons essentiellement sur le cas des plasmas de cl2 et de o2 purs. Dans cette thèse, nous étendons les résultats expérimentaux déjà présents dans la littérature : densités de charges et de neutres, températures translationnelles. En particulier, les tendances en fonction de la pression, essentielles pour la simulation, sont soigneusement étudiées. Les vibrations moléculaires sont également étudiées à l'aide d'un montage innovant de spectroscopie d'absorption. Nous montrons que les simulations sont encore loin de représenter fidèlement les processus réactionnels des plasmas étudiés. Nous tentons de fournir à cet effet quelques pistes d'améliorations. Ce travail est la base nécessaire à l'amélioration continue des plasmas industriels utilisés pour la gravure de semi-conducteurs. / Radio-frequency inductively-coupled plasmas in simple halogen gases (cl2/hbr/o2) are widely used in the semi-conductor industry. However, our knowledge of these plasmas is still incomplete. To improve it, numerous simulation studies have been performed in the last decades. Unfortunately, experimental results to compare these studies are still scarce. The objectives of this thesis is to provide a comprehensive set of experimental results. We focused on the plasmas of pure o2 and cl2. In this thesis, we extend the already available experimental results : neutral nd charges densities, translational temperatures. In particular, the tendancies of these parameters as a function of the pressure are carefully studied. Molecular vibrations are studied as well using a new kind of absorption spectroscopy setup. We show that the recent simulations are still far from representing the reactional processes in the studied plasmas. We then try to provide some ideas of improvement. This work is the needed start to improve etching plasma industrial processes.
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Strategické podnikatelské aktivity vybraného podniku / Strategic Business Activities of a chosen FirmJoštová, Alice January 2009 (has links)
The aim of this thesis is to choose two products of the telecommunication company Telefónica O2 Czech Republic, a.s. - internet ADSL/IPTV, through the sales analysis describe their development,competition, trends on the market etc. and in the end evaluate if it's efficient for the company to continue providing these services or not, choose a the best suitable strategy and simulate probable sales and revenues in 2009, 2010 and 2011. For this running average method will be used.
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Oxygen and Carbon Dioxide Levels During Qualitative Respirator Fit TestingLaferty, Edward Alan 07 October 2004 (has links)
No description available.
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Processus élémentaires associés à la réaction d’oxydation de CO à basses températures sur des catalyseurs à base de Palladium et d’Or supportés sur Al2O3 et SiO2 / Elementary processes associated to the reaction of CO oxidation at low temperatures on Palladium and Gold catalysts supported on Al2O3 and SiO2Rozé, Emmanuel 30 November 2010 (has links)
Dans cette thèse, une approche microcinétique expérimentale est utilisée pour caractériser des étapes élémentaires impliquées dans l’oxydation de CO par O2 sur des catalyseurs à base de Pd et d’Au supportés sur oxydes métalliques et identifier celles qui contrôlent la vitesse de réaction. Sur un catalyseur 1,4%Pd/Al2O3, l’évolution de la production de CO2 (RCO2(t)) par oxydation des espèces CO adsorbées (2 linéaires L et 2 pontées P) a été suivie lors de cycles successifs formation - oxydation des espèces. Une période d’induction est observée, donnant un pic de CO2 caractérisé partm et RCO2m. L’étude de l’impact de différents paramètres expérimentaux sur tm et RCO2m: le tempsde désorption avant oxydation, la pression partielle de O2, la température et le prétraitement ducatalyseur a permis de caractériser les étapes superficielles impliquées. Un modèle cinétique basé surl’oxydation des espèces CO P par une espèce oxygène faiblement adsorbée formée sur des sites libéréspar la désorption et/ou l’oxydation des espèces CO L a permis d’interpréter ces impacts. Ce modèle aégalement permis d’interpréter les différences d’activités du catalyseur vis-à-vis de la réaction CO/O2en fonction de son prétraitement après réduction sous H2 à 713 K : un refroidissement sous hydrogènepermet d’obtenir des conversions de CO proches de 100% à 300 K en excès de O2 alors qu’unedésorption préalable à 713 K donne de faibles conversions (< 4%). Ces différences sont attribuées àune reconstruction de la surface des particules de Pd par désorption de l’hydrogène à 713 K.Sur Au supporté sur Al2O3 et SiO2, l’étude a porté sur la première étape de l’oxydation du CO:l’adsorption du CO. Sous certaines conditions (température et pressions) l’adsorption de CO à 300 Kentraîne une reconstruction progressive des particules d’or modifiant significativement les propriétésdes espèces adsorbées. La cinétique de cette reconstruction à 300 K est étudiée et interprétée / The aim of this thesis is to use an experimental microkinetic approach to characterize elementary steps involved in the oxidation of CO by O2 over Pd and Au catalysts supported on Al2O3 and SiO2 and to identify those controlling the rate of the reaction. On 1.4% Pd/Al2O3, the evolution of the production of CO2 (RCO2(t)) by oxidation of the adsorbed CO species (2 linear L and 2 bridged B) was followed during successive formationoxidation cycles. An induction period is observed leading to a CO2 peak characterized by tm and RCO2m. The study of the impacts of different experimental parameters on tm and RCO2m such as the duration of a desorption before oxidation, the partial pressure of O2, the temperature and thepretreatment of the catalyst allows us to characterize the different surface elementary steps of thereaction. A kinetic model is proposed which is based on the oxidation of the B CO species by a weaklyadsorbed O species formed on Pd sites liberated by the desorption and the oxidation of the L COspecies. This model allows us to interpret the differences in the catalytic activity of the catalyst for theCO/O2 reaction according to the pretreatment procedure after reduction with H2 at 713 K: cooling thesolid in hydrogen permits obtaining a CO conversion of ��100% in excess O2 whereas a desorption at713 K provides CO conversions < 4%. These differences are ascribed to the reconstruction of thesurface of the Pd particles during the hydrogen desorption at 713 K. On Au/Al2O3 and Au/SiO2, the study concerns the first step of CO oxidation: the adsorption of CO. For a set of experimental conditions (Temperature and partial pressures), the adsorption of CO at 300 K leads to a progressive reconstruction of the Au particles modifying significantly the propertiesof the adsorbed species. The kinetic of this reconstruction is studied.
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Impacts géochimiques de la présence d’oxygène sur les saumures en conditions de stockage géologique de CO2 : caractérisation de solubilités. / Geological impacts of the presence of oxygen on brine in CO2 storage conditions : characterization of solubilityLanglais, Carole 10 December 2013 (has links)
TOTAL a choisi la voie du stockage géologique de CO2 en Béarn pour les fumées issues du pilote d’oxycombustion qui sont injectées dans un réservoir déplété de gaz naturel. Cependant, la mise en œuvre de cette technologie nécessite une connaissance des processus physiques, physico-chimiques et des interactions entre les phases depuis le captage jusqu’au stockage, d’autant plus que le CO2 injecté n’est pas pur. Il peut contenir par exemple quelques pourcents d’oxygène. Nous étudions plus précisément l’impact de l’injection d’un mélange de gaz (CO2 + O2) sur les roches de réservoir et de couverture en présence de saumure. A cette fin, un pilote expérimental a été développé et instrumenté pour acquérir des données thermodynamiques (solubilités et masses volumiques) et cinétiques de dégradation des roches indispensables aux modélisations et simulations thermodynamiques et réactives du système triphasique (gaz-saumure-roches) dans les conditions de stockage (T < 150°C et P < 200 bar). / TOTAL has chosen the path of geological storage of CO2 in Béarn flue gases from driver oxycombustion which are injected into a depleted natural gas reservoir. However, the implementation of this technology requires knowledge of physical processes and physico-chemical interactions between the phases from capture to storage, especially as the injected CO2 flow is not pure. It may contain a few percent of oxygen. The impact of the injection of a gas mixture (CO2 + O2) on reservoir rock and in the presence of coverage of brine is studied. An experimental pilot was developed and instrumented to acquire thermodynamic data (solubility and density) and kinetics of degradation of solids essential for modeling and simulations of thermodynamic and reactive three-phase system (gas-brine-rock) in storage conditions (T <150°C and P <200 bar).
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Etude de nouvelles voies de passivation non polymérisante pour la gravure profonde du siliciumDuluard, Corinne 27 May 2009 (has links) (PDF)
La gravure plasma de structures à fort rapport d'aspect dans le silicium est une étape clé dans la fabrication de microsystèmes et de composants de microélectronique de puissance. L'objectif de ce travail est de développer un procédé de gravure profonde du silicium, qui fonctionne à plus haute température de substrat que le procédé cryogénique en chimie plasma SF6/O2 et qui présente une meilleure stabilité en température et en concentration de gaz passivant(s). Dans ce but, de nouvelles voies de passivation non polymérisante ont été explorées. Nous avons évalué les possibilités de passivation par l'apport de SO2 en remplacement de O2. A température cryogénique, les propriétés de gravure sont semblables en plasma SF6/SO2 et SF6/O2 ; elles sont corrélées aux densités de neutres mesurées par spectrométrie de masse et actinométrie. La majeure partie des recherches a été consacrée à l'étude de la molécule SiCl4 comme précurseur de passivation. Nous avons au préalable analysé les interactions entre espèces générées en plasma SF6/SiCl4. Les expériences de caractérisation du plasma montrent que les réactions aux parois entre atomes F et espèces SiClx contrôlent la chimie du plasma et donc les propriétés de gravure du silicium. En mélange SF6/O2/SiCl4, ces réactions influent également sur la vitesse de gravure du substrat, mais l'ajout de SiCl4 à SF6/O2 a surtout pour effet de favoriser l'attaque chimique latérale. Nous avons finalement étudié la possibilité de former une couche de passivation par plasma SiCl4/O2 à température de substrat de -20 °C. Les résultats de cette étude permettent de proposer un nouveau procédé, basé sur l'alternance d'étapes de gravure par plasma SF6 et d'étapes de passivation par plasma SiCl4/O2.
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