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01123 Experimental studies of the performance of adsorbed natural gas storage system during discharge
03 Gaseous fuels (economics, business, marketing, policy) solutions used consisted of 0.1, 0.05, 0.01 and 0.005 M sodium bicarbonate (NaHCO3) for the slow strain rate testing (SSRT) technique and hydrogen permeation measurements at 50°C. Hydrogen permeation increased with solution concentration and was maximum for the quenched steel. Pre-charging of specimens with hydrogen did not have any effect on the mechanical properties of the as-received or water-sprayed steel but it did in the quenched and the quenched+tempered steels. In all the heat treatments, the mechanical properties of the steel were seriously affected only in 0.005 M NaHCO3, the steel in the quenched condition being the most susceptible. The cracking mechanism is dominated by anodic dissolution, film rupture of the steel in the as-received and water-sprayed conditions. But it was dominated by hydrogen embrittlement for the quenched and the quenched+tempered steels.
06101123 Experimental studies of the performance of adsorbed natural gas storage system during discharge Yang, X. D. et al. Applied Thermal Engineering, 2005, 25, (4), 591 601. In this work, comparative experiments were carried out to study the thermal effect of the adsorption heat on the discharge performance of an adsorbed natural gas (ANG) storage system. A storage vessel with u-shaped heat exchanging pipe round the central region was designed according to the temperature field determined by the finite element analysis of the adsorbent bed within 1 L cylinder. Discharge performances of the ANG on the activated carbon within the storage vessel were tested on a volumetrically built experimental unit. Results show that the central region of the adsorbent bed suffers from the severest temperature fluctuation in a short period of the initial discharge state; introduction of the hot water whose temperature is similar to that of the cooling water of a vehicular engine can significantly moderate the temperature fluctuation of the adsorbent bed, shorten the discharge process for about 60 % in comparing with that without the application of the supplemental heat. Conclusions are drawn that the heat from the cooling water of a vehicular engine should be a consideration to improve the discharge performance of the ANG storage system.
Economics, business, marketing, policy 06101124 A comparative study on the autoxidation of dimethyl ether (DME) comparison with diethyl ether (DEE) and diisopropyl ether (DIPE) Naito, M. et al. Journal of Loss Prevention in the Process Industries, 2005, 18, (4 6), 469 473. The Japanese government is planning to introduce DME as a substituted energy for oil and LNG. Introduction of DME could contribute greatly to both the prevention of global warming and the formation of resource-recycling societies. In these circumstances, a safety assessment of DME is very important when DME is used on a large scale. There is a possibility that prolonged exposure in air induces autoxidation to produce explosive organic peroxides during transportation and storage of DME. Therefore, the reactivity of DME with oxygen and the mechanism of the autoxidation were investigated. Accelerating Rate Calorimetry (ARC) was used to evaluate the thermal stability of DME and DIPE, a known peroxide producers, under adiabatic and various atmospheric conditions. In ARC studies of DME under oxygen, exothermic decompositions were detected although its self-heating rate was low in comparison with DIPE. Oven storage tests were carried out and iodimetry was used to measure the concentration of peroxides produced from DME in comparison with DIPE and DEE. However, no products could be found for DME either by GC/MS or by iodimetry, while some evidence of autoxidation of both DEE and DIPE were obtained from these experiments.
06•01125
A new approach to utilize Hydrogen as a safe fuel
Abdel-Aal, H. K. et al. International Journal o/" Hydrogen Energy, 2005, 30, (13 14), 1511 1514. Fundamental to the creation of a hydrogen economy is a viable, safe and affordable hydrogen-energy-system. Examining carefully some of the key properties of hydrogen that are related to fire and explosion, it is found that hydrogen is combustible over a wide range of concentrations. At atmospheric pressure, it is combustible at concentrations from 4% to 74.2% by volume. It has the highest flame velocity of any gas and its ignition energy is very low, which is 32% less than methane gas. In this paper, the problem of 'safe hydrogen' is tackled using a new theoretical approach. Hydrogen is mixed with predetermined amounts of methane gas and to be sold as 'Hydrothane'. The properties of this mixture most important are the flame speed, lower explosion limit (LEL) and upper explosion limit (UEL) are to be developed as a function of the ratio of the hydrogen methane. The maximum flame speed, cm/s, for a selected number of hydrocarbons
along with the corresponding volume percentage of combustible mixture (fuel in air) are used in the proposed analysis. In addition, Le Chatelier's law is used to predict limits of flammability of the Hydrothane.
06•01126
Coal gasification for advanced power generation
Minchener, A J. Fuel, 2005, 84, (17), 2222 2235. This paper provides a review of the development and deployment of coal based gasification technologies for power generation. The global status of gasification is described covering the various process and technology options. The use of gasification for power generation is then highlighted including the advantages and disadvantages of this means for coal utilization. The R, D & D needs and challenges are then reviewed including the likely impact of regulatory emissions directives in moving things forward.
06101127 Hydrogen infrastructure strategic planning using multi-objective optimization Hugo, A. et al. International Journal qf Hydrogen Energy, 2005, 30, (15), 1523 1534. Increasingly, hydrogen is being promoted as an alternative energy carrier for a sustainable future. Many argue that its use as a transportation fuel in fuel cell vehicles offers a number of attractive advantages over existing energy sources, especially in terms of well-towheel greenhouse gas emissions. Following this interest, several of the leading energy companies, like BP, have started investigating strategies for its introduction. The challenge of developing a future commercial hydrogen economy clearly still remains, though: what are the energy efficient, environmentally benign and cost effective pathways to deliver hydrogen to the consumer? Establishing what these 'best' pathways may be is not trivial, given that a large number of technological options exist and are still in development for its manufacturing, storage, distribution and dispensing. Cost, operability, reliability, environmental impacts, safety and social implications are all performance measures that should be considered when assessing the different pathways as viable long-term alternatives. To aid this decision-making process, a generic optimization-based model is presented for the strategic longrange investment planning and design of future hydrogen supply chains. By utilizing Mixed Integer Linear Programming (MILP) techniques, the model is capable of identifying optimal investment strategies and integrated supply chain configurations from the many alternatives. Realizing also that multiple performance criteria are of interest, the optimization is conducted in terms of both investment and environmental criteria, with the ultimate outcome being a set of optimal trade-off solutions representing conflicting infrastructure pathways. Since many agree that there is no one single template strategy for investing in a hydrogen infrastructure across the globe, emphasis is placed on developing a generic model such that it can be readily applied to different scenarios, geographical regions and case studies. As such, the model supports BP's strategic hydrogen infrastructure planning using high-level optimization programming, and is coined bpIC-H2. The features and capabilities of the model are illustrated through the application to a case study.
06•01128 Natural gas and the environmental results of life cycle assessment Riva, A. et al. Energy, 2006, 31, (1), 138 148. Life cycle assessment (LCA) is a method aimed at identifying the environmental effects connected with a given product, process or activity along its life cycle. This paper presents results of the application of LCA method in order to evaluate the environmental advantages of natural gas over other fossil fuels and to have advanced techniques for analysing the environmental aspects of the gas industry. The evaluation of published studies and the application of the method to electricity production with fossil fuels, by using data from published databases and data collected by the gas industry, demonstrate the importance and difficulties of having reliable and updated data required for a significant LCA. Results show that the environmental advantages of natural gas over the other fossil fuels in the final use stage increase still further if the whole life cycle of the fuels, from production to final consumption, is taken into account.
06•01129
Steps toward the hydrogen economy
Penner, S. S. Energy, 2006, 31, (1), 33 43. The hydrogen economy is defined as the industrial system in which one of the universal energy carriers is hydrogen (the other is electricity) and hydrogen is oxidized to water that may be reused by applying an external energy source for dissociation of water into its component elements hydrogen and oxygen. There are three different primary energy-supply system classes which may be used to implement the hydrogen economy, namely, fossil fuels (coal, petroleum, natural gas, and as yet largely unused supplies such as shale oil, oil from tar sands, natural gas from geo-pressured locations, etc.), nuclear reactors including fission reactors and breeders or fusion nuclear reactors over the very long term, and renewable energy sources (including
Fuel and Energy Abstracts
May 2006
171
06101123 Experimental studies of the performance of adsorbed natural gas storage system during discharge Yang, X. D. et al. Applied Thermal Engineering, 2005, 25, (4), 591 601. In this work, comparative experiments were carried out to study the thermal effect of the adsorption heat on the discharge performance of an adsorbed natural gas (ANG) storage system. A storage vessel with u-shaped heat exchanging pipe round the central region was designed according to the temperature field determined by the finite element analysis of the adsorbent bed within 1 L cylinder. Discharge performances of the ANG on the activated carbon within the storage vessel were tested on a volumetrically built experimental unit. Results show that the central region of the adsorbent bed suffers from the severest temperature fluctuation in a short period of the initial discharge state; introduction of the hot water whose temperature is similar to that of the cooling water of a vehicular engine can significantly moderate the temperature fluctuation of the adsorbent bed, shorten the discharge process for about 60 % in comparing with that without the application of the supplemental heat. Conclusions are drawn that the heat from the cooling water of a vehicular engine should be a consideration to improve the discharge performance of the ANG storage system.
Economics, business, marketing, policy 06101124 A comparative study on the autoxidation of dimethyl ether (DME) comparison with diethyl ether (DEE) and diisopropyl ether (DIPE) Naito, M. et al. Journal of Loss Prevention in the Process Industries, 2005, 18, (4 6), 469 473. The Japanese government is planning to introduce DME as a substituted energy for oil and LNG. Introduction of DME could contribute greatly to both the prevention of global warming and the formation of resource-recycling societies. In these circumstances, a safety assessment of DME is very important when DME is used on a large scale. There is a possibility that prolonged exposure in air induces autoxidation to produce explosive organic peroxides during transportation and storage of DME. Therefore, the reactivity of DME with oxygen and the mechanism of the autoxidation were investigated. Accelerating Rate Calorimetry (ARC) was used to evaluate the thermal stability of DME and DIPE, a known peroxide producers, under adiabatic and various atmospheric conditions. In ARC studies of DME under oxygen, exothermic decompositions were detected although its self-heating rate was low in comparison with DIPE. Oven storage tests were carried out and iodimetry was used to measure the concentration of peroxides produced from DME in comparison with DIPE and DEE. However, no products could be found for DME either by GC/MS or by iodimetry, while some evidence of autoxidation of both DEE and DIPE were obtained from these experiments.
06•01125
A new approach to utilize Hydrogen as a safe fuel
Abdel-Aal, H. K. et al. International Journal o/" Hydrogen Energy, 2005, 30, (13 14), 1511 1514. Fundamental to the creation of a hydrogen economy is a viable, safe and affordable hydrogen-energy-system. Examining carefully some of the key properties of hydrogen that are related to fire and explosion, it is found that hydrogen is combustible over a wide range of concentrations. At atmospheric pressure, it is combustible at concentrations from 4% to 74.2% by volume. It has the highest flame velocity of any gas and its ignition energy is very low, which is 32% less than methane gas. In this paper, the problem of 'safe hydrogen' is tackled using a new theoretical approach. Hydrogen is mixed with predetermined amounts of methane gas and to be sold as 'Hydrothane'. The properties of this mixture most important are the flame speed, lower explosion limit (LEL) and upper explosion limit (UEL) are to be developed as a function of the ratio of the hydrogen methane. The maximum flame speed, cm/s, for a selected number of hydrocarbons
along with the corresponding volume percentage of combustible mixture (fuel in air) are used in the proposed analysis. In addition, Le Chatelier's law is used to predict limits of flammability of the Hydrothane.
06•01126
Coal gasification for advanced power generation
Minchener, A J. Fuel, 2005, 84, (17), 2222 2235. This paper provides a review of the development and deployment of coal based gasification technologies for power generation. The global status of gasification is described covering the various process and technology options. The use of gasification for power generation is then highlighted including the advantages and disadvantages of this means for coal utilization. The R, D & D needs and challenges are then reviewed including the likely impact of regulatory emissions directives in moving things forward.
06101127 Hydrogen infrastructure strategic planning using multi-objective optimization Hugo, A. et al. International Journal qf Hydrogen Energy, 2005, 30, (15), 1523 1534. Increasingly, hydrogen is being promoted as an alternative energy carrier for a sustainable future. Many argue that its use as a transportation fuel in fuel cell vehicles offers a number of attractive advantages over existing energy sources, especially in terms of well-towheel greenhouse gas emissions. Following this interest, several of the leading energy companies, like BP, have started investigating strategies for its introduction. The challenge of developing a future commercial hydrogen economy clearly still remains, though: what are the energy efficient, environmentally benign and cost effective pathways to deliver hydrogen to the consumer? Establishing what these 'best' pathways may be is not trivial, given that a large number of technological options exist and are still in development for its manufacturing, storage, distribution and dispensing. Cost, operability, reliability, environmental impacts, safety and social implications are all performance measures that should be considered when assessing the different pathways as viable long-term alternatives. To aid this decision-making process, a generic optimization-based model is presented for the strategic longrange investment planning and design of future hydrogen supply chains. By utilizing Mixed Integer Linear Programming (MILP) techniques, the model is capable of identifying optimal investment strategies and integrated supply chain configurations from the many alternatives. Realizing also that multiple performance criteria are of interest, the optimization is conducted in terms of both investment and environmental criteria, with the ultimate outcome being a set of optimal trade-off solutions representing conflicting infrastructure pathways. Since many agree that there is no one single template strategy for investing in a hydrogen infrastructure across the globe, emphasis is placed on developing a generic model such that it can be readily applied to different scenarios, geographical regions and case studies. As such, the model supports BP's strategic hydrogen infrastructure planning using high-level optimization programming, and is coined bpIC-H2. The features and capabilities of the model are illustrated through the application to a case study.
06•01128 Natural gas and the environmental results of life cycle assessment Riva, A. et al. Energy, 2006, 31, (1), 138 148. Life cycle assessment (LCA) is a method aimed at identifying the environmental effects connected with a given product, process or activity along its life cycle. This paper presents results of the application of LCA method in order to evaluate the environmental advantages of natural gas over other fossil fuels and to have advanced techniques for analysing the environmental aspects of the gas industry. The evaluation of published studies and the application of the method to electricity production with fossil fuels, by using data from published databases and data collected by the gas industry, demonstrate the importance and difficulties of having reliable and updated data required for a significant LCA. Results show that the environmental advantages of natural gas over the other fossil fuels in the final use stage increase still further if the whole life cycle of the fuels, from production to final consumption, is taken into account.
06•01129
Steps toward the hydrogen economy
Penner, S. S. Energy, 2006, 31, (1), 33 43. The hydrogen economy is defined as the industrial system in which one of the universal energy carriers is hydrogen (the other is electricity) and hydrogen is oxidized to water that may be reused by applying an external energy source for dissociation of water into its component elements hydrogen and oxygen. There are three different primary energy-supply system classes which may be used to implement the hydrogen economy, namely, fossil fuels (coal, petroleum, natural gas, and as yet largely unused supplies such as shale oil, oil from tar sands, natural gas from geo-pressured locations, etc.), nuclear reactors including fission reactors and breeders or fusion nuclear reactors over the very long term, and renewable energy sources (including
Fuel and Energy Abstracts
May 2006
171