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02309 Cross-correlation analysis of atmospheric trace concentrations of N2O, CH4 and CO2 determined by continuous gas-chromatographic monitoring
15 Environment (pollution, health protection, safety) extending the well-being framework to include reliability worth parameters are illustrated by application to a small reliability test system designated RBTS. Customer interruption data from the four countries are used in conjunction with the RBTS subtransmission system in order to obtain the reliability worth indices.
05•02309 Cross-correlation analysis of atmospheric trace concentrations of N20 , CH 4 and CO2 determined by continuous gas-chromatographic monitoring Akimoto, F. et al. Energy, 2005, 30, (2 4), 299 311. Recently, the concentration of nitrous oxide (N20) has been studied, because N20 is a greenhouse gas whose effect per molecule is more significant than that of carbon dioxide (CO2), and also like chlorofluorocarbons (CFCs) and other ozone-destroying chemical elements it can cause ozone layer depletion. From 1996, the continuous monitoring of N20 has been done by gas-chromatography with an electron capture detector at Nagoya University (RAN) in Japan. Data of N20 were analysed together with monitoring data of CO2 and methane (CH4) at the same university, by applying power spectral density, autocorrelation and cross-correlation techniques. As a result, weak correlations between N20 and CO2 or CH4 were found though their origins are thought to be different. This suggests that they are affected by the same phenomena at least partially. Moreover, correlations with the meteorological elements probably associated with the N20 data are investigated. The paper discusses the origins of N20 in a suburb of Nagoya on the basis of temporal variations and correlations with various elements.
05•02310 Degradation of toluene and acetaldehyde with Ptloaded TiO2 catalyst and parabolic trough concentrator Sano, T. et al. Solar Energy, 2005, 77, (5), 543 552. Photocatalytic degradation of volatile organic compounds (VOCs) with Pt-loaded TiOo was analysed at elevated temperatures in the laboratory experiments (,$0 190c'C) and in the field experiments (30 230c'C). The temperature of catalyst coated on the sunlight receiver was easily elevated to around 200~'C by parabolic trough concentrator (1 m x 1 m). When gaseous toluene (15 ppm) or acetaldehyde (400 ppm) was passed through the reactor, 79% of toluene or 93% of acetaldehyde was removed continuously. In the similar condition, bare TiO2 was rapidly deactivated by the formation of byproducts. The combination of sunlight concentrator and Pt TiO2 catalyst exhibited the enhancement of complete degradation of VOCs, the inhibition of deactivation, and the reactivation of photocatalyst. The contributions of photocatalytic and catalytic activities of P~TiO2 were analysed by using UV lamp and electric heater. Acetaldehyde is thermocatalytically degraded by photodeposited Pt on TiO2 at 70 190~'C without UV irradiation, however the UV irradiation is necessary for the complete oxidation of acetaldehyde into CO2. It is inferred that the degradation of VOCs is enhanced by the combined effect of Pt thermocatalyst and P~TiO2 photocatalyst.
05/02311 Effects of CO and H 2 on the formation of N20 via catalytic NO reduction Takigawa, A. et al. Energy, 2005, 30, (2 4), 475 484. The formation of N20 in a mixture of NO, CO, H2, O2 and N2 was investigated experimentally in a tubular-flow reactor containing a catalyst. It was found that the reduction of NO is enhanced by the presences of H2, and to a lesser extent CO, and that N20 is formed as a by-product of NH3 decomposition and NO reduction in the presence of H2, and through NO reduction in the presence of CO. The main product of NH3 oxidation is N2 in addition to the products of NO and N20, and the rate of conversion for NH3 to N20 is about 10%. The conversion of NO to N20 is higher in the presence of H2 than in the presence of CO at lower temperature, and there is a range of temperature in which the formation of N20 is enhanced in the presence of either H2 or CO, whereas CO enhances N20 production from catalytic NO reduction more than H2 in a CO/H2/NO/O2/N2 gas system.
05•02312 flames
Fuel effects on NOxemissions in partially premixed
Naha, S. and Aggarwal, S. K. Combustion andFlame, 2004, 139, (1 2), 90 105. The requirement to significantly reduce NO~ and particulate emissions while maintaining combustor performance is one of the main drivers for internal combustion engine research. Partially premixing and using fuel blends represent two promising approaches for reducing both the NO~ and the particulate emissions from flames. This paper reports on the results of a numerical investigation on the effects of using different fuels on NO~ emissions in counterflow partially premixed flames. The fuels investigated include methane, n-heptane, and their blends with hydrogen. The methane flame is computed using the GRI-3.0 mechanism, while the n-heptane flame is computed by combining the Held et al. oxidation mechanism with the Li and Williams NO~ mechanism. Results indicate that, with regard to their NO~ character-
istics, partially premixed flames can be grouped into two distinct regimes, namely a double-flame regime, characterized by high levels of partial premixing and/or low strain rates (as) with two physically separated reaction zones, and a merged-flame regime, characterized by low levels of partial premixing and/or high as with nearly merged reaction zones. In the first regime, NO~ characteristics of both methane and n-heptane flames are strongly affected by changes in equivalence ratio (40 and strain rate, while in the second regime, they exhibit a relatively weak dependence on 4) and as. In addition, the n-heptane and methane flames established under identical conditions exhibit widely different NO~ emission behaviour in the first regime but qualitatively similar behaviour in the second regime. Major differences include (i) significantly higher NO level and NO~ emission index, (ii) much wider double-flame regime with regard to 4) and as, (iii) dominance of the prompt mechanism over the thermal mechanism in the entire partially premixed regime, and (iv) noticeable reduction in NO~ emission with hydrogen addition for n-heptane flames compared to methane flames. These differences are attributable to the different fuel pyrolysis/ oxidation chemistry of the two fuels, as the consumption of n-heptane occurs mainly through the C2 path, while that of methane occurs mainly through the C1 path. As a result, the amounts of C2H2 and, consequently, of CH radicals formed in n-heptane flames are significantly higher than those in methane flames and are responsible for the observed differences in NO~ characteristics of the two fuels.
05•02313 Fuel-based inventory of NOx and SO2 emissions from motor vehicles in the Hiroshima Prefecture, Japan Nurrohim, A. and Sakugawa, H. Applied Energy, 2005, 80, (3), 291 305. In order to attain the 2010 target of reducing national greenhouse gases by 6% to the 1990 level, with reference to the Kyoto Protocol, the Government of Japan has planned and implemented some measures, as well as related policies. This paper discusses the possible impact of these measures on the nitrogen-oxide and sulfur-dioxide emissions from road vehicles in the Hiroshima Prefecture (approximately 3 million population). The number of road vehicles based on vehicle and fuel types in the Hiroshima Prefecture for 1990 2000 are presented, as well as projections for the years 2005 and 2010 using the Gompertz model. Three scenarios were developed to assess the emissions, referring to the possible achievement of related measures and policies as well as new vehicle technologies. Prediction results show that nitrogen-oxide emissions may be decreased from 14.7 kton in 1990 to 9.3 kton in 2010 if Japanese energy-policy and new vehicle developments are successfully implemented. If they are less successfully implemented, the emissions will decrease slightly to 14 kton, in which the decrease of emissions was mostly from gasoline vehicle. The emission of sulfur dioxide was projected to decrease from 1.2 kton in 1990 to within the range 0.45 0.49 kton by 2010, as a result of measures to reduce sulfur content in diesel oil.
05•02314 Green hope or greenwash? The actions of the European Union at the World Summit on sustainable development Lightfoot, S. and Burchell, J. Global Environmental Change Part A, 2004, 14, (4), 337 344. This article examines whether the European Union (EU) could be seen as a normative power at the recent World Summit on Sustainable Development. The paper explains how the EU operationalized its commitment to the concept of sustainable development before highlighting the impact the EU had on the final summit outcomes. It shows that although in many areas the EU was able to offer leadership, internal policy coherence prevented it fully being able to develop that role and thus fully promoting the norm of sustainable development.
05•02315 Greenhouse gas emission during storage of pig manure on a pilot scale Wolter, M. et al. Bioresource Technology, 2004, 95, (3), 235 244. The greenhouse gas emissions (COz, CH4, NzO) from a 2 ton (4.4 m 3) deep litter pig manure pile (storage time 113 days during winter season) were quantified by using a tent, which covered the whole pile during the measuring periods only. The emissions were calculated in CO2 equivalents per kilogram dry matter by. Additionally the retention time (use of tracer gas SF6) and the concentrations of the gases in different parts of the pile were determined. The average retention time of the gases in the pile was less than 2 h. CH4 is assumed to have been generated only in the centre of the pile, whereas CO2 was assumed to have been generated in a wider zone. The emissions of CH4, CO2 and N20 were at the highest in the beginning when nearly the whole pile had temperatures in the range of thermophilic microorganisms. This leads to the assumption that mainly thermophilic microorganisms formed the gases. The most important gas for global warming was found to be nitrous oxide.
Fuel and Energy Abstracts
September 2005
337
05•02309 Cross-correlation analysis of atmospheric trace concentrations of N20 , CH 4 and CO2 determined by continuous gas-chromatographic monitoring Akimoto, F. et al. Energy, 2005, 30, (2 4), 299 311. Recently, the concentration of nitrous oxide (N20) has been studied, because N20 is a greenhouse gas whose effect per molecule is more significant than that of carbon dioxide (CO2), and also like chlorofluorocarbons (CFCs) and other ozone-destroying chemical elements it can cause ozone layer depletion. From 1996, the continuous monitoring of N20 has been done by gas-chromatography with an electron capture detector at Nagoya University (RAN) in Japan. Data of N20 were analysed together with monitoring data of CO2 and methane (CH4) at the same university, by applying power spectral density, autocorrelation and cross-correlation techniques. As a result, weak correlations between N20 and CO2 or CH4 were found though their origins are thought to be different. This suggests that they are affected by the same phenomena at least partially. Moreover, correlations with the meteorological elements probably associated with the N20 data are investigated. The paper discusses the origins of N20 in a suburb of Nagoya on the basis of temporal variations and correlations with various elements.
05•02310 Degradation of toluene and acetaldehyde with Ptloaded TiO2 catalyst and parabolic trough concentrator Sano, T. et al. Solar Energy, 2005, 77, (5), 543 552. Photocatalytic degradation of volatile organic compounds (VOCs) with Pt-loaded TiOo was analysed at elevated temperatures in the laboratory experiments (,$0 190c'C) and in the field experiments (30 230c'C). The temperature of catalyst coated on the sunlight receiver was easily elevated to around 200~'C by parabolic trough concentrator (1 m x 1 m). When gaseous toluene (15 ppm) or acetaldehyde (400 ppm) was passed through the reactor, 79% of toluene or 93% of acetaldehyde was removed continuously. In the similar condition, bare TiO2 was rapidly deactivated by the formation of byproducts. The combination of sunlight concentrator and Pt TiO2 catalyst exhibited the enhancement of complete degradation of VOCs, the inhibition of deactivation, and the reactivation of photocatalyst. The contributions of photocatalytic and catalytic activities of P~TiO2 were analysed by using UV lamp and electric heater. Acetaldehyde is thermocatalytically degraded by photodeposited Pt on TiO2 at 70 190~'C without UV irradiation, however the UV irradiation is necessary for the complete oxidation of acetaldehyde into CO2. It is inferred that the degradation of VOCs is enhanced by the combined effect of Pt thermocatalyst and P~TiO2 photocatalyst.
05/02311 Effects of CO and H 2 on the formation of N20 via catalytic NO reduction Takigawa, A. et al. Energy, 2005, 30, (2 4), 475 484. The formation of N20 in a mixture of NO, CO, H2, O2 and N2 was investigated experimentally in a tubular-flow reactor containing a catalyst. It was found that the reduction of NO is enhanced by the presences of H2, and to a lesser extent CO, and that N20 is formed as a by-product of NH3 decomposition and NO reduction in the presence of H2, and through NO reduction in the presence of CO. The main product of NH3 oxidation is N2 in addition to the products of NO and N20, and the rate of conversion for NH3 to N20 is about 10%. The conversion of NO to N20 is higher in the presence of H2 than in the presence of CO at lower temperature, and there is a range of temperature in which the formation of N20 is enhanced in the presence of either H2 or CO, whereas CO enhances N20 production from catalytic NO reduction more than H2 in a CO/H2/NO/O2/N2 gas system.
05•02312 flames
Fuel effects on NOxemissions in partially premixed
Naha, S. and Aggarwal, S. K. Combustion andFlame, 2004, 139, (1 2), 90 105. The requirement to significantly reduce NO~ and particulate emissions while maintaining combustor performance is one of the main drivers for internal combustion engine research. Partially premixing and using fuel blends represent two promising approaches for reducing both the NO~ and the particulate emissions from flames. This paper reports on the results of a numerical investigation on the effects of using different fuels on NO~ emissions in counterflow partially premixed flames. The fuels investigated include methane, n-heptane, and their blends with hydrogen. The methane flame is computed using the GRI-3.0 mechanism, while the n-heptane flame is computed by combining the Held et al. oxidation mechanism with the Li and Williams NO~ mechanism. Results indicate that, with regard to their NO~ character-
istics, partially premixed flames can be grouped into two distinct regimes, namely a double-flame regime, characterized by high levels of partial premixing and/or low strain rates (as) with two physically separated reaction zones, and a merged-flame regime, characterized by low levels of partial premixing and/or high as with nearly merged reaction zones. In the first regime, NO~ characteristics of both methane and n-heptane flames are strongly affected by changes in equivalence ratio (40 and strain rate, while in the second regime, they exhibit a relatively weak dependence on 4) and as. In addition, the n-heptane and methane flames established under identical conditions exhibit widely different NO~ emission behaviour in the first regime but qualitatively similar behaviour in the second regime. Major differences include (i) significantly higher NO level and NO~ emission index, (ii) much wider double-flame regime with regard to 4) and as, (iii) dominance of the prompt mechanism over the thermal mechanism in the entire partially premixed regime, and (iv) noticeable reduction in NO~ emission with hydrogen addition for n-heptane flames compared to methane flames. These differences are attributable to the different fuel pyrolysis/ oxidation chemistry of the two fuels, as the consumption of n-heptane occurs mainly through the C2 path, while that of methane occurs mainly through the C1 path. As a result, the amounts of C2H2 and, consequently, of CH radicals formed in n-heptane flames are significantly higher than those in methane flames and are responsible for the observed differences in NO~ characteristics of the two fuels.
05•02313 Fuel-based inventory of NOx and SO2 emissions from motor vehicles in the Hiroshima Prefecture, Japan Nurrohim, A. and Sakugawa, H. Applied Energy, 2005, 80, (3), 291 305. In order to attain the 2010 target of reducing national greenhouse gases by 6% to the 1990 level, with reference to the Kyoto Protocol, the Government of Japan has planned and implemented some measures, as well as related policies. This paper discusses the possible impact of these measures on the nitrogen-oxide and sulfur-dioxide emissions from road vehicles in the Hiroshima Prefecture (approximately 3 million population). The number of road vehicles based on vehicle and fuel types in the Hiroshima Prefecture for 1990 2000 are presented, as well as projections for the years 2005 and 2010 using the Gompertz model. Three scenarios were developed to assess the emissions, referring to the possible achievement of related measures and policies as well as new vehicle technologies. Prediction results show that nitrogen-oxide emissions may be decreased from 14.7 kton in 1990 to 9.3 kton in 2010 if Japanese energy-policy and new vehicle developments are successfully implemented. If they are less successfully implemented, the emissions will decrease slightly to 14 kton, in which the decrease of emissions was mostly from gasoline vehicle. The emission of sulfur dioxide was projected to decrease from 1.2 kton in 1990 to within the range 0.45 0.49 kton by 2010, as a result of measures to reduce sulfur content in diesel oil.
05•02314 Green hope or greenwash? The actions of the European Union at the World Summit on sustainable development Lightfoot, S. and Burchell, J. Global Environmental Change Part A, 2004, 14, (4), 337 344. This article examines whether the European Union (EU) could be seen as a normative power at the recent World Summit on Sustainable Development. The paper explains how the EU operationalized its commitment to the concept of sustainable development before highlighting the impact the EU had on the final summit outcomes. It shows that although in many areas the EU was able to offer leadership, internal policy coherence prevented it fully being able to develop that role and thus fully promoting the norm of sustainable development.
05•02315 Greenhouse gas emission during storage of pig manure on a pilot scale Wolter, M. et al. Bioresource Technology, 2004, 95, (3), 235 244. The greenhouse gas emissions (COz, CH4, NzO) from a 2 ton (4.4 m 3) deep litter pig manure pile (storage time 113 days during winter season) were quantified by using a tent, which covered the whole pile during the measuring periods only. The emissions were calculated in CO2 equivalents per kilogram dry matter by. Additionally the retention time (use of tracer gas SF6) and the concentrations of the gases in different parts of the pile were determined. The average retention time of the gases in the pile was less than 2 h. CH4 is assumed to have been generated only in the centre of the pile, whereas CO2 was assumed to have been generated in a wider zone. The emissions of CH4, CO2 and N20 were at the highest in the beginning when nearly the whole pile had temperatures in the range of thermophilic microorganisms. This leads to the assumption that mainly thermophilic microorganisms formed the gases. The most important gas for global warming was found to be nitrous oxide.
Fuel and Energy Abstracts
September 2005
337