Academic literature on the topic 'Sulphur dioxide – Analysis'
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Journal articles on the topic "Sulphur dioxide – Analysis"
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Palmer, Anne S., Vin I. Morgan, Mark A. J. Curran, Tas D. van Ommen, and Paul A. Mayewski. "Antarctic volcanic flux ratios from Law Dome ice cores." Annals of Glaciology 35 (2002): 329–32. http://dx.doi.org/10.3189/172756402781816771.
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AbstractExplosive volcanic eruptions can inject large quantities of sulphur dioxide into the stratosphere. the aerosols that result from oxidation of the sulphur dioxide can produce significant cooling of the troposphere by reflecting or absorbing solar radiation. It is possible to obtain an estimate of the relative stratospheric sulphur aerosol concentration produced by different volcanoes by comparing sulphuric acid fluxes determined by analysis of polar ice cores. Here,we use a non-sea-salt sulphate time series derived from three well-dated Law Dome ice cores to investigate sulphuric acid flux ratios for major eruptions over the period AD 1301–1995. We use additional data from other cores to investigate systematic spatial variability in the ratios. Only for the Kuwae eruption (Law Dome ice date AD 1459.5) was the H2SO4 flux larger than that deposited by Tambora (Law Dome ice date AD 1816.7).
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Rakitskaya, Tatyana L., Tatyana A. Kiose, E. V. Kameneva, and V. Ya Volkova. "Natural Clinoptilolite Based Solid-State Compositions for Low-Temperature Air Purification from Sulphur Dioxide." Solid State Phenomena 230 (June 2015): 291–96. http://dx.doi.org/10.4028/www.scientific.net/ssp.230.291.
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Natural clinoptilolite (N-CLI) and N-CLI based solid-state compositions containing copper(II) chloride and halide ions (X- = Cl-, Br- or I-) were investigated by X‑ray diffraction phase analysis, IR spectroscopy, thermogravimetry, water vapour adsorption, and pH‑metry. After that, they were tested in the reaction of low-temperature sulphur dioxide oxidation with air oxygen. It has been found that N-CLI has no protective properties in respect of sulphur dioxide whereas CuCl2‑KX/N-CLI compositions have the significant protective activity in the process of air purification from sulphur dioxide increasing in the order Cl- < Br- < I-.
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Shanthi, K., and N. Balasubramanian. "Method for the sampling and analysis of sulphur dioxide." Fresenius' Journal of Analytical Chemistry 351, no. 7 (1995): 685–86. http://dx.doi.org/10.1007/bf00323348.
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Liu, S., Han-xi Shen, Jian-xing Feng, and Matthieu Tubino. "Gas-permeation continuous flow coulometric analysis: determination of sulphur dioxide." Fresenius' Journal of Analytical Chemistry 357, no. 8 (April 28, 1997): 1045–49. http://dx.doi.org/10.1007/s002160050302.
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Byanju, R. M., M. B. Gewali, and K. Manandhar. "Low cost Passive Monitoring of Nitrogen dioxide and Sulphur dioxide in ambient air." Journal of Nepal Chemical Society 27 (July 16, 2012): 34–45. http://dx.doi.org/10.3126/jncs.v27i1.6439.
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Standard nitrogen dioxide (NO2) and sulphur dioxide (SO2) monitoring techniques require expensive instrumentation which is not easily adapted for large scale monitoring by resource limited countries. This paper presents the use of locally available relatively cheaper polyethylene tubes to be developed as passive diffusive sampler and use for monitoring of ambient nitrogen dioxide and sulphur dioxide using Triethanolamine (TEA) as absorbent. After extraction with double distilled water, modified Griese-Saltzmann method and West-Gaeke method were used for analysis of nitrite and sulphate adduct formed due to reaction of NO2 and SO2 respectively with TEA using spectrophotometer. The results are successfully compared with other standard methods. The detection limits and precision of the method as expressed as Coefficient of variation are good enough for monitoring of NO2 and SO2 in ambient air.DOI: http://dx.doi.org/10.3126/jncs.v27i1.6439 J. Nepal Chem. Soc., Vol. 27, 2011 34-45Uploaded date: 16 July, 2012
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Kumar, Anil. "Spectral and Statistical Analysis of Nitrogen Dioxide and Sulphur Dioxide Air Pollutants using Wavelet Transforms." Invertis Journal of Science & Technology 14, no. 2 (2021): 97–103. http://dx.doi.org/10.5958/2454-762x.2021.00010.x.
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Masneuf-Pomarède, Isabelle, and Denis Dubourdieu. "Yeast strains role on the sulphur dioxyde combinations of wines obtained from noble rot and raisining grapes." OENO One 34, no. 1 (March 31, 2000): 27. http://dx.doi.org/10.20870/oeno-one.2000.34.1.1013.
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<p style="text-align: justify;">The influence of four industrial and indigenous yeast strains on the sulphur dioxide combinations of wines obtained from noble rot and raisining grapes is studied in different growth of the Sauternes area and one growth in the Jurançon area. The analysis of ketonic compounds (pyruvic acid and 2-oxo-glutaric acid), acetaldehyde and PC50 on the wines clearly showed significant statistical difference between the yeast strains for the sulphur dioxide combination. By adding the same dosage of sulphiting, the free SO<sub>2</sub> levels are variable depending on the yeast strain used. One strain (Zymaflore ST), isolated from a spontaneous fermentation of a botrytised must, giving wines with low PC50 values, is well adapted for the noble rot must vinification. The choice of the yeast strain is a parameter of importance to limit the sulphur dioxide amount in the wines.</p>
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Granados, M., S. Maspoch, and M. Blanco. "Determination of sulphur dioxide by flow injection analysis with amperometric detection." Analytica Chimica Acta 179 (1986): 445–51. http://dx.doi.org/10.1016/s0003-2670(00)84490-6.
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Grekas, Nikos, and Antony C. Calokerinos. "Continuous flow molecular emission cavity analysis of sulphite and sulphur dioxide." Analyst 110, no. 4 (1985): 335. http://dx.doi.org/10.1039/an9851000335.
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Mondal, M. K. "Mathematical Modeling of Wet Magnesia Flue Gas Desulphurization Process." Modelling and Simulation in Engineering 2008 (2008): 1–6. http://dx.doi.org/10.1155/2008/871479.
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Desulphurization of flue gases from various chemical industries in a techno-econo-enviro manner is a demanding technology. The concentrations of sulphur dioxide in and around these plants overshoot the danger point. In recent years, the process analysis of chemical absorption in a slurry has become important in rational design and development of wet scrubbing processes for the removal ofSO2from flue gases. The elementary steps encountered in wet scrubbing by slurries are diffusion and reaction of gaseous species and solid dissolution in liquid film. In the present work, the process of the absorption of sulphur dioxide into wet magnesia slurry was theoretically analyzed according to the two-reaction plane model incorporating the solid dissolution promoted by the reactions with absorbed sulphur dioxide in the liquid film. A model based on Fick's second law has been developed to calculate enhancement factor for absorption of Sulphur dioxide intoMg(OH)2slurry. The concentration of accumulated species in the bulk of the liquid phase (sulphite ions for this case) which substantially control the absorption rates was included in the model for the prediction of theoretical enhancement factor. The values of theoretical enhancement factors obtained from model were compared with experimental enhancement factors available in literature. The model values of enhancement factors agreed well with the values of experimental enhancement factor available in literature.
Dissertations / Theses on the topic "Sulphur dioxide – Analysis"
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Thornton, David Phillip. "The New Zealand National Environmental Standards for ambient air quality: analysis and modelling case study." Thesis, University of Canterbury. Geography, 2007. http://hdl.handle.net/10092/1501.
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Historically, the New Zealand rationale behind air quality management has been to adopt an effects-based approach based on environmental impacts. Generally, this method has been efficient in that it permitted emitters to decide how to minimise and mitigate impacts. However, to address the inconsistencies in air quality management across New Zealand born of this approach, and to permit measures designed to improve the working of the Resource Management Act (RMA), National Environmental Standards for Ambient Air Quality have been developed and implemented to establish consistent regulation and protection for all New Zealanders. The standards were gazetted in September 2004, for full implementation by 2013. This thesis explores the implementation of the National Environmental Standards for Ambient Air Quality, examining the philosophy behind the standards and associated strategies for dealing with air pollution management in New Zealand, and the international context for the development of appropriate tools to address air quality concerns. The research also provides an independent dispersion modelling assessment of the application of the Ministry for the Environment's initiative regarding sulphur dioxide in the Marsden Point airshed, Northland, utilising The Air Pollution Model (TAPM) for a period when heightened concentration values had been recorded. The key outcomes of the thesis are: (i) 99.9th percentile and maximum values for the simulated two-day modelling case study are within those stipulated by the air quality standards for sulphur dioxide; (ii) modelled concentrations associated with shipping within the airshed of interest contribute significantly to total modelled values; (iii) the chief obstruction to increased use of the prognostic modelling approach is that of the unsatisfactory availability and integrity of emission inventories; (iv) performing long-term high-resolution simulations with multiple point sources is prohibitive due to computational demands; (v) good quality monitoring will always be required; (vi) the standards have broad and far-reaching implications for resource managers, resource users and possibly the economy of individual regions and the country as a whole; (vii) the successful implementation of the National Environmental Standards for Ambient Air Quality in New Zealand will integrate a thorough understanding of modelling, measurements, meteorology and emissions.
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Ngeleka, Tholakele Prisca. "Sulphur dioxide capture under fluidized bed combustion conditions / Tholakele Prisca Ngeleka." Thesis, North-West University, 2005. http://hdl.handle.net/10394/1416.
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An investigation was undertaken to determine the feasibility of increasing the hydrogen
production rate by coupling the water gas shift (WGS) process to the hybrid sulphur process
(HyS). This investigation also involved the technical and economical analysis of the water gas
shift and the H2 separation by means of Pressure swing adsorption (PSA) process. A technical
analysis of the water gas shift reaction was determined under the operating conditions selected
on the basis of some information available in the literature. The high temperature system (HTS)
and low temperature system (LTS) reactors were assumed to be operated at temperatures of
350ºC and 200ºC, respectively. The operating pressure for both reactors was assumed to be 30
atmospheres. The H2 production rate of the partial oxidation (POX) and the WGS processes was
242T/D, which is approximately two times the amount produced by the HyS process alone. The
PSA was used for the purification process leading to a hydrogen product with a purity of
99.99%. From the total H2 produced by the POX and the WGS processes only 90 percent of H2
is recovered in the PSA. The unrecovered H2 leaves the PSA as a purge gas together with CO2
and traces of CH4, CO, and saturated H2O. The estimated capital cost of the WGS plant with
PSA is about US$50 million. The production cost is highly dependent on the cost of all of the
required raw materials and utilities involved. The production cost obtained was US $1.41/kg H2
based on the input cost of synthesis gas as produced by the POX process. In this case the
production cost of synthesis gas based on US $6/GJ for natural gas and US $0/Ton for oxygen
was estimated to be US $0.154/kg. By increasing the oxygen and natural gas cost, the
corresponding increase in synthesis gas has resulted in an increase in H2 production cost of US $1.84/kg.Thesis (M.Sc. (Chemical Engineering))--North-West University, Potchefstroom Campus, 2006.
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Wang, Xiao-Yu. "Spatial analysis of long-term exposure to air pollution and cardiorespiratory mortality in Brisbane, Australia." Queensland University of Technology, 2008. http://eprints.qut.edu.au/16627/.
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Air pollution is ranked by the World Health Organisation as one of the top ten contributors to the global burden of disease and injury. Epidemiological studies have shown that exposure to air pollution is associated with cardiorespiratory diseases. However, most of the previous studies have looked at this issue using air pollution data from a single monitoring site or average values from a few monitoring sites in a city. There is increasing concern that the relationships between air pollution and mortality may vary with geographical area, particularly for a big city. This thesis consisted of three interlinked studies that aimed to examine the spatial variation in the relationship between long-term exposure to air pollution and cardiorespiratory mortality in Brisbane, Australia. The first study evaluated the long-term air pollution trends in Brisbane, Australia. Air pollution data used in this study were provided by the Queensland Environmental Protection Agency (QEPA). The data comprised the daily average concentrations of particulate matter less then 10 µm in aerodynamic diameter (PM10), nitrogen dioxide (NO2), ozone (O3) and sulphur dioxide (SO2) between 1 January 1980 and 31 December 2004 in two monitoring sites (i.e. Eagle farm and Rocklea), and in other available monitoring sites between 1 January 1996 and 31 December 2004. Computerised data files of daily mortality between 1 January 1996 and 31 December 2004 in Brisbane city were provided by the Office of Economic and Statistical Research of the Queensland Treasury. Population data and the Socio-Economic Indexes for Areas (SEIFA) data in 2001 were obtained from the Australian Bureau of Statistics (ABS) for each statistical local area (SLA) of the Brisbane city. The long-term air pollution (the daily maximum 1-hour average or daily 24-hour average concentrations of NO2, O3 and PM10) trends were evaluated using a polynomial regression model in two monitoring sites (Eagle Farm and Rocklea) in Brisbane, Australia, between 1980 and 2003. The study found that there were significant up-and-down features for air pollution concentrations in both monitoring sites in Brisbane. Rocklea recorded a substantially higher number of days with concentrations above the relevant daily maximum 1-hour or 24-hour standards than that in Eagle Farm. Additionally, there was a significant spatial variation in air pollution concentrations between these areas. Therefore, the results indicated a need to examine the spatial variation in the relationship between long-term exposure to air pollution and cardiorespiratory mortality in Brisbane. The second study examined the spatial variation of SO2 concentrations and cardiorespiratory mortality in Brisbane between 1999 and 2001. Air pollutant concentrations were estimated using geographical information systems (GIS) techniques at a SLA level. Spatial distribution analysis and a multivariable logistic regression model were employed to investigate the impact of gaseous air pollution on cardiorespiratory mortality after adjusting for potential confounding effects of age, sex, calendar year and SEIFA. The results of this study indicate that for every 1 ppb increase in annual average SO2 concentration, there was an estimated increase of 4.4 % (95 % confidence interval (CI): 1.4 - 7.6 %) and 4.8 % (95 % CI: 2.0 - 7.7 %) in cardiovascular and cardiorespiratory mortality, respectively. We estimated that the excess number of cardiorespiratory deaths attributable to SO2 was 312 (3.4% of total cardiorespiratory deaths) in Brisbane during the study period. Our results suggest that long-term exposure to SO2, even at low levels, is a significant hazard to population health. The final study examined the association of long-term exposure to gaseous air pollution (including NO2, O3 and SO2) with cardiorespiratory mortality in Brisbane, Australia, 1996 - 2004. The pollutant concentrations were estimated using GIS techniques at a SLA level. Logistic regression was used to investigate the impact of NO2, O3 and SO2 on cardiorespiratory mortality after adjusting for potential confounding effects of age, sex, calendar year and SEIFA. The study found that there was an estimated 3.1% (95% CI: 0.4 - 5.8%) and 0.5% (95% CI: -0.03 - 1.3 %) increase in cardiorespiratory mortality for 1 ppb increment in annual average concentration of SO2 and O3, respectively. However there was no significant relationship between NO2 and cardiorespiratory mortality observed in the multiple gaseous pollutants model. The results also indicated that long-term exposure to gaseous air pollutants in Brisbane, even at the levels lower than most cities in the world (especially SO2), were associated with cardiorespiratory mortality. Therefore, spatial patterns of gaseous air pollutants and their impact on health outcomes need to be assessed for an evaluation of long-term effects of air pollution on population health in metropolitan areas. This study examined the relationship between air pollution and health outcomes. GIS and relevant mapping technologies were used to display the spatial patterns of air pollution and cardiorespiratory mortality at a SLA level. The results of this study show that long-term exposure to gaseous air pollution was associated with cardiorespiratory mortality in Brisbane and this association appeared to vary with geographic area. These findings may have important public health implications in the control and prevention of air pollution-related health effects, since now many countries and governments have paid more attention to control wide spread air pollution and to protect our environment and human health.
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"Flow injection analysis of bismuth, ammonia and sulphur dioxide." Chinese University of Hong Kong, 1986. http://library.cuhk.edu.hk/record=b5885675.
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Kinsela, Andrew Stephen School of Biological Earth & Environmental Sciences UNSW. "Volatile sulfur compounds in coastal acid sulfate soils, northern N.S.W." 2007. http://handle.unsw.edu.au/1959.4/40889.
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The cycling of biogenic volatile sulfur compounds (VSCs) within marine and terrestrial ecosystems has been shown to play an integral role in atmospheric chemistry; by influencing global climate change through the creation of cloud condensation nuclei and controlling acid-base chemistry; as well as influencing sediment chemistry including the interactions with trace metals, particularly regarding iron sulfide formation. Despite this, the examination of VSCs within Australian coastal acid sulfate soils (ASS) is an unexplored area of research. As ASS in Australia occupy an area in excess of 9 M ha, there is a clear need for a greater understanding of the cycling of these compounds within such systems. This thesis looks at the concentrations of several VSCs within agricultural and undisturbed ASS on the east coast of Australia. Initial measurements of sulfur dioxide (SO2) were made using passive diffusion samplers, which were followed by two detailed field-based studies looking at the concentrations and fluxes of both SO2 and hydrogen sulfide (H2S) using flux-gradient micrometeorological techniques. These novel results indicated that this agricultural ASS was a substantial source of atmospheric H2S (0.036-0.056 gSm-2yr-1), and SO2 (0.095-0.31 gSm-2yr-1), with flux values equating to many other salt- and freshwater marshes and swamps. The flux data also suggested that the ASS could be a continual source of H2S which is photo-oxidised during the daytime to SO2. Measurements of both compounds showed separate, inverse correlations to temperature and moisture meteorological parameters indicating possible contributing and / or causal release factors. Further identification of these and other VSCs within ASS samplers was undertaken in the laboratory using gas chromatography in combination with solid-phase microextraction. Although SO2 and H2S were not discovered within the headspace samples, two other VSCs important in atmospheric sulfur cycling and trace metal geochemistry were quantified; dimethylsulfide (DMS; > 300??g/L) and ethanethiol (ESH > 4??g/L). The measurements of H2S, DMS and ESH are the first quantifications with Australian ASS, and they may be important for refining regional or local atmospheric sulfur budgets, as well as interpreting previous SO2 emissions from ASS. Ultimately this thesis further enhances our understanding of the cycling of VSCs within acid sulfate systems.
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Longo, Bernadette Mae. "The Kilauea Volcano adult health study, Hawai'i, U.S.A." Thesis, 2005. http://hdl.handle.net/1957/29845.
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Young, Adri. "'n Vergelykende studie tussen Pt en Pd vir die elektro-oksidasie van waterige SO₂ asook ander model elektrochemiese reaksies / Adri Young." Thesis, 2014. http://hdl.handle.net/10394/12104.
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The pressure on clean and sustainable energy supplies is increasing. In this regard energy conversion by electrochemical processes plays a major role, for both fuel cell reactions and electrolysis reactions. The sulphur dioxide oxidation reaction (SOR) is a common reaction found in the Hybrid Sulphur Cycle (HyS) and the HyS is a way to produce large-scale hydrogen (H2). The problem with the use of the HyS and fuel cells is the cost involved as large amounts of Pt are required for effective operation. The aim of the study was to determine whether there was an alternative catalyst which was more efficient and cost-effective than Pt. The oxygen reduction reaction (ORR), the ethanol oxidation reaction (EOR) and SOR were studied by means of different electrochemical techniques (cyclovoltammetry (CV), linear polarization (LP) and rotating disk electrode (RDE)) on polycrystalline platinum (Pt) and palladium (Pd). The SRR and EOR are common reactions occurring at the cathode and anode, respectively, in fuel cells and these reactions have been investigated extensively. The reason for studying the reactions was as a preparation for the SOR.
This study compared polycrystalline Pt and Pd for the different reactions, with the main focus on the SOR as Pd is considerably cheaper than Pt, and for the SOR polycrystalline Pd has by no means been investigated intensively. Polycrystalline Pt and Pd were compared by different electrochemical techniques and analyses. The Koutecky-Levich and Levich analyses were used to (i) calculate the number of e- involved in the relevant reaction, (ii) to determine whether the reaction was mass transfer controlled at high overpotentials and (iii) whether the reaction mechanism changed with potential. Next the kinetic current density ( k) was calculated from Koutecky-Levich analyses, which was further used for Tafel slope analyses. If it was not possible to carry out the analyses, the activation energy (Ea) was used to determine the electrocatalytic activity of the catalyst. The electrocatalytic activity was also determined by comparing onset potentials (Es), peak potentials (Ep) and limited/maximum current density ( b/ p) of each catalyst. This study was only a preliminary study for the SOR and therefore, further studies are certainly required. It seemed Pd shows better electrocatalytic activity than Pt for the SRR in an alkaline electrolyte because of similar Es, but Pd produced a higher cathodic current density. Pt showed a lower Es than Pd for the SRR in an acid electrolyte, but Pd delivered a higher cathodic current density. This, therefore, means that the SRR in an acid electrolyte is kinetically more favourable on Pd than on Pt. For the EOR better electrocatalytic activity was obtained with Pd than with Pt in an alkaline electrolyte due to higher current densities at lower potentials and Pd showed lower Ea values than Pt in the potential range normally used for fuel cells. Pd was inactive for EOR in an acid electrolyte, while a reaction occurred on Pt. A possible reason for this observation may be due to the H2 absorbing strongly on Pd thus blocking the active positions on the electrode surfaces, preventing further reaction. Pd showed higher electrocatalytic activity for the SOR due to lower Es and higher current densities at low potentials.
From the RDE studies it was established that the SRR in an alkaline electrolyte on polycrystalline Pt and Pd was mass transfer controlled at low potentials (high overpotentials), but the SRR in an acid electrolyte was only mass transfer controlled on Pt. The SOR was not mass transfer controlled on polycrystalline Pt and Pd at high potentials (high overpotentials). These assumptions were confirmed by Levich analysis.
Using Koutecky-Levich analysis, it was determined that the reaction mechanism on polycrystalline Pt and Pd changed with potential for SRR in an alkaline electrolyte and the SOR. For the SRR in an acid electrolyte the reaction mechanism remained constant with changes in potential on polycrystalline Pd, but the reaction mechanism on polycrystalline Pt changed with potential. These assumptions were confirmed by the number of e-, calculated using Koutecky-Levich analyses. Levich and Koutecky-Levich analyses were not performed for EOR as an increase in rotation speed did not produce an increase in current density.
Tafel slope analyses were conducted by making use of overpotentials and k, where possible. As in the case of ethanol, it was not possible to execute Koutecky-Levich analyses and, therefore, it was not possible to perform Tafel slope analyses using k. Tafel slope analyses for the EOR was therefore performed with normal current densities at 0 rotations per minute (rpm). The reaction mechanisms on Pt and Pd for the SRR in alkaline and acidic electrolytes differed due to different Tafel slopes. Pt and Pd displayed similar Tafel slopes for the EOR in alkaline electrolyte, thus suggesting that the reaction mechanisms on Pt and Pd were the same. For the SOR it seemed that the reaction mechanism on Pt and Pd were similar because of similar Tafel slopes. This was only a preliminary and comparative study for polycrystalline Pt and Pd, and the reaction mechanism was not further studied by means of spectroscopic techniques.MSc (Chemistry), North-West University, Potchefstroom Campus, 2014
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Eliades, John Alexander. "A Radio Frequency Quadrupole Instrument for use with Accelerator Mass Spectrometry: Application to Low Kinetic Energy Reactive Isobar Suppression and Gas–phase Anion Reaction Studies." Thesis, 2012. http://hdl.handle.net/1807/32706.
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A radio frequency (rf) quadrupole instrument, currently known as an Isobar Separator for Anions (ISA), has been integrated into an Accelerator Mass Spectrometry (AMS) system to facilitate anion–gas reactions before the tandem accelerator. An AMS Cs+ sputter source provided > 15 keV ions that were decelerated in the prototype ISA to < 20 eV for reaction in a single collision cell and re-accelerated for AMS analysis. Reaction based isobar suppression capabilities were assessed for smaller AMS systems and a new technique for gas–phase reaction studies was developed.
Isobar suppression of 36S– and 12C3– for 36Cl analysis, and YF3– and ZrF3– for 90Sr analysis were studied in NO2 with deceleration to < 12 eV. Observed attenuation cross sections, σ [x 10^–15 cm^2], were σ(S– + NO2) = 6.6, σ(C3– + NO2) = 4.2, σ(YF3– + NO2) = 7.6, σ(ZrF3– + NO2) = 19. With 8 mTorr NO2, relative attenuations of S–/Cl– ~ 10^–6, C3–/Cl– ~ 10^–7, YF3–/SrF3– ~ 5 x 10^–5 and ZrF3–/SrF3– ~ 4 x 10^–6 were observed with Cl– ~ 30% and SrF3– > 90% transmission. Current isobar attenuation limits with < 1.75 MV accelerator terminal voltage and ppm impurity levels were calculated to be 36S–/Cl– ~ 4 x 10^–16, 12C3–/Cl– ~ 1.2 x 10^–16, 90YF3–/SrF3– ~ 10^–15 and 90ZrF3–/SrF3– ~ 10^–16.
Using 1.75 MV, four 36Cl reference standards in the range 4 x 10^–13 < 36Cl/Cl < 4 x 10^–11 were analyzed with 8 mTorr NO2. The measured 36Cl/Cl ratios plotted very well against the accepted values. A sample impurity content S/Cl < 6 x 10^–5 was measured and a background level of 36S–/Cl < 9 x 10^–15 was determined.
Useful currents of a wide variety of anions are produced in AMS sputter sources and molecules can be identified relatively unambiguously by stripping fragments from tandem accelerators. Reactions involving YF3–, ZrF3–, S– and SO– + NO2 in the ISA analyzed by AMS are described, and some interesting reactants are identified.
Books on the topic "Sulphur dioxide – Analysis"
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Ontario. Ministry of the Environment. Countdown acid rain: Summary and analysis of the ... progress reports by Ontario's four major sources of sulphur dioxide. [Toronto]: Ontario, Ministry of the Environment, 1986.
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Department of the Environment. Determination of Sulphite, Sulphur Dioxide, Thiosulphate and Thiocyanate, with Notes on the Determination of Total Sulphur and Other Sulphur Compounds 1985. Stationery Office Books, 1987.
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Department of the Environment. Determination of Sulphite, Sulphur Dioxide, Thiosulphate and Thiocyanate, with Notes on the Determination of Total Sulphur and Other Sulphur Compounds 1985. Stationery Office Books, 1987.
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Countdown acid rain: Summary and analysis of the second progress reports by Ontario's four major emission sources of sulphur dioxide. [Toronto]: Environment Ontario, 1987.
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Great Britain. Standing Committee of Analysts., ed. Determination of sulphite, sulfur dioxide, thiosulphate, and thiocyanate: With notes on the determination of total sulphur and other sulfur compounds, 1985 : methods for the examination of waters and associated materials. London: H.M.S.O., 1987.
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Brieda, F., K. Bull, K. W. Buhne, and M. Callais. Methods of Sampling and Analysis for Sulphur Dioxide, Oxides of Nitrogen and Particulate Matter in the Exhaust Gases of Large Combustion Plant (Envir). European Communities, 1986.
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Frew, Anthony. Air pollution. Edited by Patrick Davey and David Sprigings. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780199568741.003.0341.
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Any public debate about air pollution starts with the premise that air pollution cannot be good for you, so we should have less of it. However, it is much more difficult to determine how much is dangerous, and even more difficult to decide how much we are willing to pay for improvements in measured air pollution. Recent UK estimates suggest that fine particulate pollution causes about 6500 deaths per year, although it is not clear how many years of life are lost as a result. Some deaths may just be brought forward by a few days or weeks, while others may be truly premature. Globally, household pollution from cooking fuels may cause up to two million premature deaths per year in the developing world. The hazards of black smoke air pollution have been known since antiquity. The first descriptions of deaths caused by air pollution are those recorded after the eruption of Vesuvius in ad 79. In modern times, the infamous smogs of the early twentieth century in Belgium and London were clearly shown to trigger deaths in people with chronic bronchitis and heart disease. In mechanistic terms, black smoke and sulphur dioxide generated from industrial processes and domestic coal burning cause airway inflammation, exacerbation of chronic bronchitis, and consequent heart failure. Epidemiological analysis has confirmed that the deaths included both those who were likely to have died soon anyway and those who might well have survived for months or years if the pollution event had not occurred. Clean air legislation has dramatically reduced the levels of these traditional pollutants in the West, although these pollutants are still important in China, and smoke from solid cooking fuel continues to take a heavy toll amongst women in less developed parts of the world. New forms of air pollution have emerged, principally due to the increase in motor vehicle traffic since the 1950s. The combination of fine particulates and ground-level ozone causes ‘summer smogs’ which intensify over cities during summer periods of high barometric pressure. In Los Angeles and Mexico City, ozone concentrations commonly reach levels which are associated with adverse respiratory effects in normal and asthmatic subjects. Ozone directly affects the airways, causing reduced inspiratory capacity. This effect is more marked in patients with asthma and is clinically important, since epidemiological studies have found linear associations between ozone concentrations and admission rates for asthma and related respiratory diseases. Ozone induces an acute neutrophilic inflammatory response in both human and animal airways, together with release of chemokines (e.g. interleukin 8 and growth-related oncogene-alpha). Nitrogen oxides have less direct effect on human airways, but they increase the response to allergen challenge in patients with atopic asthma. Nitrogen oxide exposure also increases the risk of becoming ill after exposure to influenza. Alveolar macrophages are less able to inactivate influenza viruses and this leads to an increased probability of infection after experimental exposure to influenza. In the last two decades, major concerns have been raised about the effects of fine particulates. An association between fine particulate levels and cardiovascular and respiratory mortality and morbidity was first reported in 1993 and has since been confirmed in several other countries. Globally, about 90% of airborne particles are formed naturally, from sea spray, dust storms, volcanoes, and burning grass and forests. Human activity accounts for about 10% of aerosols (in terms of mass). This comes from transport, power stations, and various industrial processes. Diesel exhaust is the principal source of fine particulate pollution in Europe, while sea spray is the principal source in California, and agricultural activity is a major contributor in inland areas of the US. Dust storms are important sources in the Sahara, the Middle East, and parts of China. The mechanism of adverse health effects remains unclear but, unlike the case for ozone and nitrogen oxides, there is no safe threshold for the health effects of particulates. Since the 1990s, tax measures aimed at reducing greenhouse gas emissions have led to a rapid rise in the proportion of new cars with diesel engines. In the UK, this rose from 4% in 1990 to one-third of new cars in 2004 while, in France, over half of new vehicles have diesel engines. Diesel exhaust particles may increase the risk of sensitization to airborne allergens and cause airways inflammation both in vitro and in vivo. Extensive epidemiological work has confirmed that there is an association between increased exposure to environmental fine particulates and death from cardiovascular causes. Various mechanisms have been proposed: cardiac rhythm disturbance seems the most likely at present. It has also been proposed that high numbers of ultrafine particles may cause alveolar inflammation which then exacerbates preexisting cardiac and pulmonary disease. In support of this hypothesis, the metal content of ultrafine particles induces oxidative stress when alveolar macrophages are exposed to particles in vitro. While this is a plausible mechanism, in epidemiological studies it is difficult to separate the effects of ultrafine particles from those of other traffic-related pollutants.
Book chapters on the topic "Sulphur dioxide – Analysis"
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Giannitrapani, Marco, Adrian Bowman, E. Marian Scott, and Ron Smith. "Additive Models for Sulphur Dioxide Pollution in Europe." In Statistical Methods for Trend Detection and Analysis in the Environmental Sciences, 265–82. Chichester, UK: John Wiley & Sons, Ltd, 2011. http://dx.doi.org/10.1002/9781119991571.ch7.
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Kuroki, Akihiro. "Analysis of the effects of environmental regulation: A case study on countermeasures against sulphur dioxide in Japan." In Energy and Environment Regulation, 25–37. London: Palgrave Macmillan UK, 1996. http://dx.doi.org/10.1007/978-1-349-25057-8_2.
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Kavouras, Ioannis, Eftychios Protopapadakis, Maria Kaselimi, Emmanuel Sardis, and Nikolaos Doulamis. "Assessing the Lockdown Effects on Air Quality During COVID-19 Era." In Frontiers in Artificial Intelligence and Applications. IOS Press, 2021. http://dx.doi.org/10.3233/faia210095.
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In this work we investigate the short-term variations in air quality emissions, attributed to the prevention measures, applied in different cities, to mitigate the COVID-19 spread. In particular, we emphasize on the concentration effects regarding specific pollutant gases, such as carbon monoxide (CO), ozone (O3), nitrogen dioxide (NO2) and sulphur dioxide (SO2). The assessment of the impact of lockdown on air quality focused on four European Cities (Athens, Gladsaxe, Lodz and Rome). Available data on pollutant factors were obtained using global satellite observations. The level of the employed prevention measures is employed using the Oxford COVID-19 Government Response Tracker. The second part of the analysis employed a variety of machine learning tools, utilized for estimating the concentration of each pollutant, two days ahead. The results showed that a weak to moderate correlation exists between the corresponding measures and the pollutant factors and that it is possible to create models which can predict the behaviour of the pollutant gases under daily human activities.
Conference papers on the topic "Sulphur dioxide – Analysis"
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Zhou, Hesheng. "Primary analysis of sulphur dioxide pollution and its sources in Chengdu." In Asia-Pacific Symposium on Remote Sensing of the Atmosphere, Environment, and Space, edited by Upendra N. Singh, Huanling Hu, and Gengchen Wang. SPIE, 1998. http://dx.doi.org/10.1117/12.319515.
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Allan, W. D., D. Gardiner, L. Bennett, M. LaViolette, G. Pucher, and M. Turingia. "Emissions Testing From the Use of Various Biodiesel Blends in Representative Canadian Army Equipment." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-43511.
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A comprehensive series of emissions measurements were taken from two pieces of equipment used by the Canadian Forces. A field kitchen burner unit and the engine from the Light Armoured Vehicle III (LAVIII) were operated using two base fuels: low and ultra low sulphur diesel fuel blended with three different biofuels. Methylesters from canola, tallow and yellow grease were mixed in a range of volumetric proportions from 0 to 20%. Additionally, both very low sulphur diesel and aviation turbine fuel (JP-8) were tested against neat low sulphur diesel fuel. The complete chemical analysis conducted on all test fuels will not be presented here. A full range of gaseous emission measurements were obtained including oxides of nitrogen, unburnt hydrocarbons, carbon monoxide and dioxide and limited sulphur dioxide measurements. Two means of monitoring particulate matter were used with one proving to be more effective than the other. Novel techniques were used to obtain the burner unit emissions results and the AVL 8-mode test sequence was applied to the Caterpillar engine from the LAVIII. Although emission trends were detected, levels were often on the margins of perceptibility of the gas analysis system, and atmospheric conditions were challenging. Nevertheless, a methodology was developed and refined. Some correlations were made between the chemical analysis and emissions results. The testing will allow the Canadian Army to estimate its emissions footprint.
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Selby, K., M. Urbanak, D. Colbourne, H. Leonhardt, P. Burnett, F. Machatschek, and S. Beviere. "Meeting the Lubrication Challenges of Heavy Duty Low Emission Diesel Engines." In World Tribology Congress III. ASMEDC, 2005. http://dx.doi.org/10.1115/wtc2005-63983.
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In recent years, legislative authorities in the US, Europe and Japan have steadily reduced engine exhaust emissions, i.e., carbon monoxide (CO), hydrocarbons (HC), sulphur, particulate matter (PM) and nitrogen oxides (NOx) to improve air quality. To meet these requirements engine manufacturers have had to make significant design changes and as a consequence new engine lubricant specifications from Industry bodies (ACEA, EMA, JAMA) and individual OEMs have had to be introduced to ensure adequate lubrication of these new engines. This has led to significant changes to heavy-duty diesel engine oil (HDDEO) oil formulation composition. Engine design modifications to increase fuel combustion efficiency such as increased peak cylinder pressure and increased fuel injection pressures have placed higher stress on piston rings and liners, bearings and valve train components [1], and improved oil consumption has meant longer oil residence time in the piston ring belt area. The practice of retarded fuel injection timing and exhaust gas recirculation (EGR) as measures to reduce NOx levels by reducing peak combustion temperature has had a considerable impact on lubricant performance. Retarded injection leads to higher soot levels which can cause valve train wear and piston ring liner wear and soot-induced thickening, whilst EGR leads to increased corrosive acids and wear in the combustion chamber. Currently in Europe, Euro 3 heavy-duty engines predominantly use retarded fuel injection as the primary NOx emission control strategy although there are cases where EGR is used. In the US, cooled EGR is used by most engine manufacturers to meet US 2002 emissions. HDDEO’s contain a combination of performance additives such as overbased metal detergents, dispersants, antiwear agents and antioxidants designed to provide wear protection, engine cleanliness, and control of soot contaminants and oxidation. Other additive components include selected viscosity index (VI) improvers and pour point depressants to provide necessary viscosity characteristics and shear stability, and also anti-foam agents for oil aeration control. To meet the increased demands from low emission engines, the chemical composition of the performance additives has been modified and levels increased. Current HDDEOs optimized to meet US and European specifications contain typically between 1.3 and 1.9%wt sulphated ash, 0.1–0.14%wt phosphorus and 0.3–1.1.wt sulphur. To meet the next generation emission standards, engines will require the use of exhaust after-treatment devices. In Europe, Euro 4 emission reductions for NOx and PM, scheduled for introduction in 2005, will require the use of either selective catalytic reduction, or the use of EGR in combination with a diesel particulate filter (DPF). To meet the US 2007 requirements, higher levels of EGR than currently used, in combination with DPFs, is envisaged by most engine builders. Exhaust after-treatment devices are already used extensively in some applications such as DPFs on city buses in Europe and the US. Further NOx restrictions are scheduled for Euro 5 in 2008 and USA in 2010. NOx absorber systems, although used in gasoline engines, are still under development for heavy-duty diesel engines and may be available for 2010. Some lubricant base oil and additive components from oil consumed in the combustion chamber are believed to adversely affect the performance of after-treatment devices. Ash material from metal detergents and zinc dithiophosphates (ZDTP) can build up in the channels within particulate filters causing blockage and potentially loss of engine power, leading to a need for frequent cleaning maintenance. The role of sulphur and phosphorus in additive components is less clear. Sulphur from fuel can either oxidize to sulphur dioxide and react through to sulphuric acid, which manifests itself as particulate, or can have a poisoning effect on the catalyst itself. However, the role of sulphur containing additives is yet to be established. Phosphorus from ZDTP antiwear components can lead to a phosphate layer being deposited on catalyst surfaces, which may impair efficiency. Concerns from OEMs regarding the possible effects of ash, sulphur and phosphorus has led to chemical limits being introduced in some new and upcoming engine oil specifications. The ACEA E6 sequence restricts sulphated ash to 1.0%wt max, phosphorus to 0.08%wt max and sulphur to 0.3%wt max, while the PC-10 category scheduled for 2007 will have maximum limits of 1.0%wt sulphated ash, 0.12%wt phosphorus and 0.4%wt sulphur. The resulting constraints on the use of conventional overbased metal detergent cleanliness additives and zinc dithiophosphate antiwear additives will necessitate alternative engine oil formulation technologies to be developed in order to maintain current performance levels. Indeed, performance requirements of engine oils are expected to become more demanding for the next generation engines where emissions are further restricted. If absorbers become a major route for NOx reduction, limits on sulphur and phosphorus are likely to be more restrictive. Oil formulations meeting ACEA E6 and PC-10 chemical limits have been assessed in several key critical lubricant specification tests, looking at valve train and piston ring/cylinder liner wear, corrosive wear in bearings, piston cleanliness and soot-induced viscosity control. It is demonstrated that it is possible to achieve MB 228.5 extended oil drain performance and API CI-4 wear, corrosion and piston cleanliness requirements for current US engines equipped with EGR [2], at a sulphated ash level of 1.0%wt, and phosphorus and sulphur levels, (0.05 and 0.17%wt, respectively), considerably lower than these chemical limits. This is achievable by the use of selected low sulphur detergents, optimized primary and secondary antioxidant systems and non-phosphorus containing, ashless supplementary antiwear additives blended in synthetic basestocks. Field trials in several city bus fleets have been conducted to assess engine oil performance and durability using one of these low sulphated ash, phosphorus and sulphur (SAPS) oil formulations and to examine lubricant effects on particulate filter performance. Engine oil durability testing was conducted in bus fleets in Germany and Switzerland. These trials, involving over 100 vehicles, cover a range of engine types, e.g., Daimler Chrysler and MAN Euro 1, 2 and 3 and different fuel types (low sulphur diesel, biodiesel, and compressed natural gas) in some MAN engines. The fleets are fitted with continuously regenerating particulate filters either from new or retrofitted. Oils were tested at standard and extended drain intervals (up to 60 000km). Used oil analysis for iron, copper, lead and aluminium with the low SAPS oil in these vehicles have shown low wear rates in all engine types and comparable with a higher 1.8% ash ACEA E4, E5 quality oil. Soot levels can vary considerably, but oil viscosity is maintained within viscosity grade, even at 8% soot loading. TBN depletion and TAN accumulation rates are low showing significant residual basicity reserve and control of acidic combustion and oxidation products. Buses in Stuttgart and Berlin have been used to investigate lubricant ash effects of engine oil on particulate filter durability. Exhaust back-pressure is routinely measured and DPF filters removed and cleaned when back pressure exceeds 100 mbar. Comparison of rate of back pressure build up as a function of vehicle distance shows reduced back pressure gradients for the low SAPS oil relative to the 1.8%wt ash oil in both engine types looked at. An average reduction in back pressure gradient of 40% was found in buses equipped with OM 906LA engines in Berlin and 25% with OM 457hLA engines at both locations. Examination of the ash content in DPFs has shown a 40% reduction in the quantity of ash with the low SAPS oil. This investigation shows that it is possible to meet current long oil drain requirements whilst meeting chemical limits for future lubricants and provide benefits in DPF durability.
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Palit, Samiddha, Bijan Kumar Mandal, Sudip Ghosh, and Arup Jyoti Bhowal. "Performance and Emission Characteristics of Bio-Diesel as an Alternative Diesel Engine Fuel." In ASME 2008 2nd International Conference on Energy Sustainability collocated with the Heat Transfer, Fluids Engineering, and 3rd Energy Nanotechnology Conferences. ASMEDC, 2008. http://dx.doi.org/10.1115/es2008-54283.
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Fast depletion of the conventional petroleum-based fossil fuel reserves and the detrimental effects of the pollutant emissions associated with the combustion of these fuels in internal combustion (IC) engines propelled the exploration and development of alternative fuels for internal combustion engines. Biodiesel has been identified as one of the most promising alternative fuels for IC engines. This paper discusses about the advantages and disadvantages of biodiesel vis-a-vis the conventional petro-diesel and presents the energetic performances and emission characteristics of CI engine using biodiesel and biodiesel-petrodiesel blends as fuels. An overview of the current research works carried out by several researchers has been presented in brief. A review of the performance analysis suggests that biodiesel and its blends with conventional diesel have comparable brake thermal efficiencies. The energy balance studies show that biodiesel returns more than 3 units of energy for each unit used in its production. However, the brake specific fuel consumption increases by about 9–14% compared to diesel fuel. But, considerable improvement in environmental performance is obtained using biodiesel. There is significant reduction in the emissions of unburned hydrocarbons, polyaromatic hydrocarbons (PAHs), soot, particulates, carbon monoxide, carbon dioxide and sulphur dioxide with biodiesel. But the NOx emission is more with biodiesel compared to diesel. A case study with Jatropha biodiesel as fuel and the current development status, both global and Indian, of biodiesel as a CI engine fuel have been included in the paper.
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Desideri, U., P. Lunghi, and R. Burzacca. "State of the Art About the Effects of Impurities on MCFCs and Pointing Out of Additional Research for Alternative Fuel Utilization." In ASME 2003 1st International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2003. http://dx.doi.org/10.1115/fuelcell2003-1739.
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Fuel cells are very flexible energy conversion devices and in particular MCFC power generating system are among the most promising for stationary power generation. Potentially, MCFCs can be fed by a great variety of gaseous fuels comprising low calorific values gases like landfill gas. Thanks to fuel processing technologies, like gasification, suitable anode input gases can also be obtained from solid matters. Coal, but also RDF (Refuse Derived Fuel), industrial waste and biomasses are potential fuels for the fuel cell technology after a specific treatment aimed to yield a proper gas for the cell requirements. The gases mentioned above are characterized by low calorific values, presence of inert gases, presence of carbon monoxide and dioxide, presence of various contaminants such as chlorine, sulphur and nitrogen compounds or metals and they can be utilized for power production in high temperature fuel cell units only after a proper clean-up treatment (tars, particulate and sulphur removal). Although interest in alternative fuels for fuel cells has spread in the recent years, most research activity related to fuel treatment has been performed on methane. The biggest drawback deriving from this situation is a general lack of information. When present, moreover, the information is often contradictory. An example of this is given by the acceptable contaminants levels for molten carbonate fuel cells about which there are not values that are based on sufficient experimental evidence. Unfortunately the design of a clean-up system, the choice of the best technology, the optimization of the BOP relies just on these values. In this work a literature research and an analysis of the present knowledge about the effect of impurities in fuel for fuel cells has been preformed. The goal is the definition of concentration levels that can be tolerated by MCFCs and the degradation in performance or the reduction of cell life related to the presence of different pollutants. A second step of the work is the comparison of the levels of impurities tolerated by the cells with those present in the different low calorific value gases in order to define the clean-up requirements. The research priorities in this field have been pointed out. Finally, the project of the fuel cell team of University of Perugia about this topic is briefly described.
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Tourlidakis, A., A. Malkogianni, and E. Karlopoulos. "Combined Heat and Power Generation for a Small Municipality for District Heating Purposes, Using Different Fuels." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95840.
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Environmental concerns related to climate change are forcing many countries to consider implementing cogeneration of heat and power with centralized heating systems (i.e. district heating networks) which are becoming increasingly widespread in many countries. Combined heat and power (CHP) or cogeneration is the simultaneous production of electricity and useful thermal energy. The big interest this technology is receiving, both globally and locally, has its reason in the chance of reducing fuel consumption by enhancing energy production processes. The considerable amount of waste heat associated to traditional power stations is transformed into useful heat, which can be sent through the district network to houses and buildings for heating or cooling. Considering the pollution district heating reduce local pollutants such as dust, sulphur dioxide and nitrogen oxides by replacing exhausts from individual boilers. In addition to the reduced use of fuels, far more effective pollution prevention and control measures can be taken in central production facilities. The purpose of this paper is to present the results of the investigation for the installation of a small-scale CHP plant for District Heating purposes in a small municipality in Northern Greece. Initially the heat and electricity demands were estimated based on a combination of historical consumption data, the construction features of the buildings and the weather conditions in the region. A pipe network was designed and sized appropriately and the utilization of a CHP plant was studied. Additionally, a number of various fuel options were considered such as natural gas, oil, pulverised coal and biomass from crop and forest residues, and also animal waste. The availability in biomass in the local region was estimated and it was found that it could cover a small percentage of approximately 5% of the required heating power. Finally, a techno-economic analysis was carried out and the CO2 reduction benefits were estimated.
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Allen, J. W., K. R. Parker, and A. Sanyal. "Coal Quality and Its Impact on Power Stations Emissions Control." In ASME 2005 Power Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/pwr2005-50196.
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Although coal fired power generation plant was originally designed to operate on a particular coal, increasingly stringent emissions regulations have led to modifications to both the coal type and firing mode. Low sulphur (S) coals minimize the requirement for sulphur dioxide (SO2) scrubbing plant combustion modifications are used as the primary measure to reduce the emission of nitrogen oxides (NOx) and these changes in the firing regime and/or the coal type can also impact on the in boiler ash deposition, particulate collection and the overall efficiency of the boiler operation. Emission regulations requiring maximum NOx levels of 0.15lbs./MM.Btu. are at, or just below, the limit of NOx reduction achievable by primary measures and at this limit significant increases in unburnt carbon (UBC) in ash levels can be expected, which affect boiler efficiency and also the operation of any SO2 and particulate collection plant. Coals are usually purchased, in addition to price, on quality based on the well established proximate and ultimate analyses, whereas parameters derived from these basic analyses may be more effective in defining the behaviour of a coal, substituted for the original design coal, in order to meet current emissions regulations whilst still maintaining an acceptable operating efficiency.