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Effect of the use of a gas motor in a biomass-based electric power plant
10 Engines (power generation and propulsion, electrical vehicles) steam addition, the production rates of HCN and N radicals decrease dramatically, and NO formation is suppressed as a whole. These results may be useful to predict NOx emissions in a high-temperature gas turbine system with steam or water addition.
03100738 Control of nitrogen injection into gas turbine combustors for reduced nitrogen oxide emissions, especially in combined-cycle power generation Arar, M. I. and Hadley, J. M. U.S. Pat. Appl. Publ. US 2002 88,236 (CI. 60-781; F02C3/283, 11 Jul 2002, Appl, 758,718, 11 Jan 2001.8. A nitrogen compressor in an IGCC (integrated gasification, combinedcycle) system, for combustion of fuel gas in the turbine combustor, provides gaseous nitrogen to be directly injected for reduction of total NO,, emissions. The nitrogen is injected at substantially the same pressure as the output pressure from the nitrogen compressor. The compressor is controlled to adjust the output pressure of the nitrogen to match the nitrogen injection pressure of the combustor. By controlling the flow (pressure) of the nitrogen injected to a combustor of a gas turbine at the nitrogen compressor, the compressor does not have to overcome the pressure loss through the nitrogen injection valves (which are run at or near full open throughout the operation of the nitrogen injection process).
03100739 Design studies of mobile applications with SOFCheat engine modules Winkler, W. and Lorenz, H. Journal of Power Sources, 2002, 106, (1-2), 338-343. The recent development of thin tubular solid oxide fuel cells (SOFCs), microturbines and Stirling engines has inspired design studies of the integration of a SOFC-heat engine (HE) system within a car. The total power system consists of a SOFC-HE power generation unit, a power storage (battery) system, a power management system and electric motors at the wheels. The sizes of the HE and the SOFC stack are to be matched by the start-up requirements. The use of micro tubes allows a very high power density of the stack. The thermodynamic calculation of the cycle gives the actual design values for the study and indicates further steps for system optimization. The first SOFC-GT layout lead to an electric efficiency of 45% for the cycle used as a base for a design study. The design study shows that the space available in a mid-class car allows the integration of such a system including space reserves. A further improvement of the system might allow an electric efficiency of more than 55%. The integration of a Stirling engine instead of the microturbine is a second possibility and the object of an ongoing study. This was motivated by interesting results from the development of solar powered Stirling engines. Generally, the analyses show that the optimal match of the SOFC and the HE will be a key issue for any engineering solution.
03/00740 Development of general-purpose software to analyze the steady state of power generation systems Koda, E. and Takahashi, T. Energy Conversion and Management, 2002, 43, (9-12), 1407-1416. it is important to improve the power generation efficiency of thermal power generation while promoting the location of nuclear power generation to reduce discharge of carbon dioxide from the power generation plants. Software, which effectively examines the performance of the power generation system of various configurations, can contribute to the development of highly effective environmental thermal power generation systems. For this purpose, the authors developed a new method to calculate the steady state of power generation systems, such as heat and mass balance, efficiencies, etc. This method is very flexible in calculation condition setting. Following on from this, a general-purpose software was developed by which the steady state behaviour of the power generation system is analysed easily.
03/00741 Effect of the use of a gas motor in a biomassbased electric power plant Jurado, F. e/aL Energy Sources, 2002, 24, (8), 743-751. Biomass gasification is a technology that transforms solid biomass into gas. A gasifier is capable of converting wood into a gaseous fuel that is fed into a gas motor. The gas motor controller regulates both the gas motor and the gas motor generator. In this paper tw o fuzzy logic controllers have been developed using speed and mechanical power deviations, and a neural network has been designed to tune the gains of the fuzzy logic controllers based on the operating conditions of the biomass-based electric power plant.
03/00742 Ethanol reforming for hydrogen production in a hybrid electric vehicle: process optimisation Klouz, V. et al. Journal of Power Sources, 2002, I, (5), 26-34. This work is focused at optimizing an ethanol reforming process over a Ni/Cu catalyst to produce a hydrogen rich stream in order to feed a solid polymer fuel cell (SPFC). The effect of the reaction temperature,
HzO/EtOH and O2/EtOH molar ratios of the feed to the reformer was studied under diluted conditions in order to maximize the hydrogen content and the COz/COx molar ratio at the outlet of the ethanol reformer. Based on the experimental results, a detailed kinetic scheme of the ethanol reforming was discussed as a function of the temperature, special attention was paid to the role of oxygen in the reaction selectivity and coke formation. Moreover, the coke nature was evaluated by transmission electron microscopy (TEM) and TPO and TPH experiments. The tests carried out at on-board reformer conditions allowed a hydrogen rich mixture (33%) in the outlet reformer flow that can be further increased by water gas sift reactions downstream. The high hydrogen content of the flow to the fuel cell together with the stability of the Ni/Cu catalyst, fully demonstrated by long time runs, can be considered of high interest for SPFC applications.
03•00743 Fuel economy and life-cycle cost analysis of a fuel cell hybrid vehicle Kwi, S. J. and Byeong, S. O. Journal of Power Sources, 2002, 105, (1), 58-65. The most promising vehicle engine that can overcome the problem of present internal combustion is the hydrogen fuel cell. Fuel cells are devices that change chemical energy directly into electrical energy without combustion. Pure fuel cell vehicles and fuel cell hybrid vehicles (i.e. a combination of fuel cell and battery) as energy sources are studied. Considerations of efficiency, fuel economy, and the characteristics of power output in hybridization of fuel cell vehicle are necessary. In the case of Federal Urban Driving Schedule (FUDS) cycle simulation, hybridization is more efficient than a pure fuel cell vehicle. The reason is that it is possible to capture regenerative braking energy and to operate the fuel cell system within a more efficient range by using battery. Life-cycle cost is largely affected by the fuel cell size, fuel cell cost, and hydrogen cost. When the cost of fuel cell is high, hybridization is profitable, but when the cost of fuel cell is less than 400 US$/kW, a pure fuel cell vehicle is more profitable.
03/00744 Further research zero CO2 emission power production: the 'COOLENERG' process Staicovici, M. D. Energy, 2002, 27, (9), 831 844. Trans-critical CO2 quasi-combined cycles have recently been systematically analysed, in order that the zero emission fuel-fired power units concept may be promoted. A 0.35-0.49 efficiency of such cycles-based plants were reported, in spite of the power use for 02 production and COz condensation. In this paper, a zero emission CO2 capture power process and plant, COOLENERG (CO2 Loop for Energy and Nature, Enhanced by Refrigeration and Gas-turbines), a patent filed by the author, is thermodynamically modelled. The plant is operated by a CO2 quasi-combined two-stage gas-turbine cycle with CH4 gas burning in an O2/recycled CO2 mixture. It originally uses the advanced thermal absorption technology in cogeneration of power and cooling for its own benefit. Technical calculations show an important benefit of the COOLENERG, expressed by the net power efficiency (0.54), which is more than 1.09 times higher than that of COOPERATE working with same parameters. The increase of the advanced absorption unit efficiency favours the net global efficiency of the power plant and promotes safer and cheaper transport and disposal of the condensed CO2 to the sequestering place. The economic assessment indicates a payback period of 3.5-7 months of the COOLENERG additional investment as compared to COOPERATE.
03/00745 cycle
Industrial applications of the air bottoming
Korobitsyn, M. Energy Conversion and Management, 2002, 43, (9-123, 1311-1322. An air bottoming cycle (ABC) was proposed in the late 1980s as an alternative for the conventional steam bottoming cycle. Now this cycle is being considered as a compact and simple bottoming cycle in various applications: as an upgrading option for simple-cycle gas turbines in the offshore industry; as a hot-air cogeneration plant; or as a heat recovery installation at high-temperature furnaces. This paper evaluates the technical and economic feasibility of the ABC in the cogeneration scheme, where hot air from the air turbine is supplied to food processing industries (industrial bakeries and milk powder factories). Another application is the heat recovery unit of a glassmelting furnace. In this option the air turbine driven by waste heat also provides pre-heated air to the furnace. Based on the results of this study, two demonstration projects are scheduled for realization with support from a governmental agency and industrial partners.
03/00746 Internal combustion engine cleaning compositions Hayward, J. PCT Int. Appl. WO 02 55,640 (CI. C11D1/72) 18 Jul 2002, GB Appl. 2001/28,736 Nov 2001. 15.
Fuel and Energy Abstracts
March 2003 99
03100738 Control of nitrogen injection into gas turbine combustors for reduced nitrogen oxide emissions, especially in combined-cycle power generation Arar, M. I. and Hadley, J. M. U.S. Pat. Appl. Publ. US 2002 88,236 (CI. 60-781; F02C3/283, 11 Jul 2002, Appl, 758,718, 11 Jan 2001.8. A nitrogen compressor in an IGCC (integrated gasification, combinedcycle) system, for combustion of fuel gas in the turbine combustor, provides gaseous nitrogen to be directly injected for reduction of total NO,, emissions. The nitrogen is injected at substantially the same pressure as the output pressure from the nitrogen compressor. The compressor is controlled to adjust the output pressure of the nitrogen to match the nitrogen injection pressure of the combustor. By controlling the flow (pressure) of the nitrogen injected to a combustor of a gas turbine at the nitrogen compressor, the compressor does not have to overcome the pressure loss through the nitrogen injection valves (which are run at or near full open throughout the operation of the nitrogen injection process).
03100739 Design studies of mobile applications with SOFCheat engine modules Winkler, W. and Lorenz, H. Journal of Power Sources, 2002, 106, (1-2), 338-343. The recent development of thin tubular solid oxide fuel cells (SOFCs), microturbines and Stirling engines has inspired design studies of the integration of a SOFC-heat engine (HE) system within a car. The total power system consists of a SOFC-HE power generation unit, a power storage (battery) system, a power management system and electric motors at the wheels. The sizes of the HE and the SOFC stack are to be matched by the start-up requirements. The use of micro tubes allows a very high power density of the stack. The thermodynamic calculation of the cycle gives the actual design values for the study and indicates further steps for system optimization. The first SOFC-GT layout lead to an electric efficiency of 45% for the cycle used as a base for a design study. The design study shows that the space available in a mid-class car allows the integration of such a system including space reserves. A further improvement of the system might allow an electric efficiency of more than 55%. The integration of a Stirling engine instead of the microturbine is a second possibility and the object of an ongoing study. This was motivated by interesting results from the development of solar powered Stirling engines. Generally, the analyses show that the optimal match of the SOFC and the HE will be a key issue for any engineering solution.
03/00740 Development of general-purpose software to analyze the steady state of power generation systems Koda, E. and Takahashi, T. Energy Conversion and Management, 2002, 43, (9-12), 1407-1416. it is important to improve the power generation efficiency of thermal power generation while promoting the location of nuclear power generation to reduce discharge of carbon dioxide from the power generation plants. Software, which effectively examines the performance of the power generation system of various configurations, can contribute to the development of highly effective environmental thermal power generation systems. For this purpose, the authors developed a new method to calculate the steady state of power generation systems, such as heat and mass balance, efficiencies, etc. This method is very flexible in calculation condition setting. Following on from this, a general-purpose software was developed by which the steady state behaviour of the power generation system is analysed easily.
03/00741 Effect of the use of a gas motor in a biomassbased electric power plant Jurado, F. e/aL Energy Sources, 2002, 24, (8), 743-751. Biomass gasification is a technology that transforms solid biomass into gas. A gasifier is capable of converting wood into a gaseous fuel that is fed into a gas motor. The gas motor controller regulates both the gas motor and the gas motor generator. In this paper tw o fuzzy logic controllers have been developed using speed and mechanical power deviations, and a neural network has been designed to tune the gains of the fuzzy logic controllers based on the operating conditions of the biomass-based electric power plant.
03/00742 Ethanol reforming for hydrogen production in a hybrid electric vehicle: process optimisation Klouz, V. et al. Journal of Power Sources, 2002, I, (5), 26-34. This work is focused at optimizing an ethanol reforming process over a Ni/Cu catalyst to produce a hydrogen rich stream in order to feed a solid polymer fuel cell (SPFC). The effect of the reaction temperature,
HzO/EtOH and O2/EtOH molar ratios of the feed to the reformer was studied under diluted conditions in order to maximize the hydrogen content and the COz/COx molar ratio at the outlet of the ethanol reformer. Based on the experimental results, a detailed kinetic scheme of the ethanol reforming was discussed as a function of the temperature, special attention was paid to the role of oxygen in the reaction selectivity and coke formation. Moreover, the coke nature was evaluated by transmission electron microscopy (TEM) and TPO and TPH experiments. The tests carried out at on-board reformer conditions allowed a hydrogen rich mixture (33%) in the outlet reformer flow that can be further increased by water gas sift reactions downstream. The high hydrogen content of the flow to the fuel cell together with the stability of the Ni/Cu catalyst, fully demonstrated by long time runs, can be considered of high interest for SPFC applications.
03•00743 Fuel economy and life-cycle cost analysis of a fuel cell hybrid vehicle Kwi, S. J. and Byeong, S. O. Journal of Power Sources, 2002, 105, (1), 58-65. The most promising vehicle engine that can overcome the problem of present internal combustion is the hydrogen fuel cell. Fuel cells are devices that change chemical energy directly into electrical energy without combustion. Pure fuel cell vehicles and fuel cell hybrid vehicles (i.e. a combination of fuel cell and battery) as energy sources are studied. Considerations of efficiency, fuel economy, and the characteristics of power output in hybridization of fuel cell vehicle are necessary. In the case of Federal Urban Driving Schedule (FUDS) cycle simulation, hybridization is more efficient than a pure fuel cell vehicle. The reason is that it is possible to capture regenerative braking energy and to operate the fuel cell system within a more efficient range by using battery. Life-cycle cost is largely affected by the fuel cell size, fuel cell cost, and hydrogen cost. When the cost of fuel cell is high, hybridization is profitable, but when the cost of fuel cell is less than 400 US$/kW, a pure fuel cell vehicle is more profitable.
03/00744 Further research zero CO2 emission power production: the 'COOLENERG' process Staicovici, M. D. Energy, 2002, 27, (9), 831 844. Trans-critical CO2 quasi-combined cycles have recently been systematically analysed, in order that the zero emission fuel-fired power units concept may be promoted. A 0.35-0.49 efficiency of such cycles-based plants were reported, in spite of the power use for 02 production and COz condensation. In this paper, a zero emission CO2 capture power process and plant, COOLENERG (CO2 Loop for Energy and Nature, Enhanced by Refrigeration and Gas-turbines), a patent filed by the author, is thermodynamically modelled. The plant is operated by a CO2 quasi-combined two-stage gas-turbine cycle with CH4 gas burning in an O2/recycled CO2 mixture. It originally uses the advanced thermal absorption technology in cogeneration of power and cooling for its own benefit. Technical calculations show an important benefit of the COOLENERG, expressed by the net power efficiency (0.54), which is more than 1.09 times higher than that of COOPERATE working with same parameters. The increase of the advanced absorption unit efficiency favours the net global efficiency of the power plant and promotes safer and cheaper transport and disposal of the condensed CO2 to the sequestering place. The economic assessment indicates a payback period of 3.5-7 months of the COOLENERG additional investment as compared to COOPERATE.
03/00745 cycle
Industrial applications of the air bottoming
Korobitsyn, M. Energy Conversion and Management, 2002, 43, (9-123, 1311-1322. An air bottoming cycle (ABC) was proposed in the late 1980s as an alternative for the conventional steam bottoming cycle. Now this cycle is being considered as a compact and simple bottoming cycle in various applications: as an upgrading option for simple-cycle gas turbines in the offshore industry; as a hot-air cogeneration plant; or as a heat recovery installation at high-temperature furnaces. This paper evaluates the technical and economic feasibility of the ABC in the cogeneration scheme, where hot air from the air turbine is supplied to food processing industries (industrial bakeries and milk powder factories). Another application is the heat recovery unit of a glassmelting furnace. In this option the air turbine driven by waste heat also provides pre-heated air to the furnace. Based on the results of this study, two demonstration projects are scheduled for realization with support from a governmental agency and industrial partners.
03/00746 Internal combustion engine cleaning compositions Hayward, J. PCT Int. Appl. WO 02 55,640 (CI. C11D1/72) 18 Jul 2002, GB Appl. 2001/28,736 Nov 2001. 15.
Fuel and Energy Abstracts
March 2003 99