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02305 Alkali separation in steam injected cyclone wood powder gasifier for gas turbine application
10
conditions. The technique operates in inert environments to isolate the thermal deactivation mechanisms from possible oxidative mechanisms occurring in true combustion experiments. The technique, based on an inert-gas-purged, refractory-metal, high-temperature wire mesh, is demonstrated here on monomaceral-rich fractions from four parent coals of diverse origin. The results show that char reactivity is quite sensitive to preparation conditions in the range of interest to combustion, decreasing by a factor of 30-50 between 1000°C and 1800°C in only 2 s of treatment for seven of eight samples examined. The 1800°C chars have similar reactivities to boiler fly-ash chars measured previously, lending support for the thermal deactivation hypothesis. The results also show that thermal deactivation propensity is a function of precursor, with vitrinite-rich fractions deactivating more readily than inertinite-rich fractions. The propensity for deactivation is shown to correlate with the extent of crystal order development as observed by high-resolution TEM fringe imaging. The relationship between fuel chemistry and deactivation propensity, as well as the implications of the reactivity results for combustion processes are discussed in the paper.
10
Engines (power generation
and propulsion,
electrical vehicles)
mounted on the engine spark plug, but in Diesel engines, the transducer must be mounted separately. The main scope of the present work is to examine the effect of the transducer position on the measured pressure diagram in high speed diesel engines. For this purpose, in the present work, a theoretical investigation is conducted using a simulation model developed by the authors, where the unsteady flow problem in the connecting pipeline from the combustion chamber to the transducer is solved using a finite difference scheme. The operation of a high speed diesel engine at various conditions is simulated with a simple combustion model. The results reveal the limits within which the pressure measurements are reliable and may be possibly used to develop a method for correcting the measured pressure diagram.
Impact of energy efficient motors in the petrochemical industry F;_ele5r. K. F. and Pillay, P. Electric Power Systems Research, 1997, 42, (1)
96lO2306
An in-depth survey of moors in two chemical plants of similar size is reported. The energy and demand savings potential was determined and hence the dollar savings using a sliding rate structure currently applicable to the petrochemical industry in Louisiana. Energy and demand savings were determined with extensive use of the MotorMaster programme.
ENGINES Method and apparatus for coal direct combustion gas-turbine combined-cycle power generation with alkali metal vapor stripping
98/02309
Power Generation and Propulsion, Electrical Vehicles Alkali separation in steam injected cyclone wood powder gasifier for gas turbine application
96lo2305
Fredriksson, C. and Kjellstrom, B. Dev. Thermochem. Biomass Convers., A. V. and Boocock, D. G. B., 1997, 2, 921-931. Edited by Bridgwater, Blackie, London, UK. A study of cyclone gasification of wood powder at atmospheric pressure was conducted. The cyclone gasifier also works as a particle separator and the wood powder is injected into the cyclone with air or air or steam as the transport medium. The effects of stoichiometry and steam injection on the gasification temperature and separation of char particles were investigated, and the experimental results compared with theoretical predictions. The amount of potassium and sodium that can be separated together with the char was also studied since this is of special interest if the gas is used to operate a gas turbine. The fuel flow was 26 kg/h corresponding to a thermal input of 140 kW. The equivalence ratio varied from 0.15 and 0.4. Wood powder was injected with air only or air and steam with steam mass flows of 50-80% of the fuel flow. It has been possible to separate 20-40% of the potassium and lo-20% of the sodium supplied with the wood, and as a result the alkali content in the gas entering a turbine at a temperature of 850°C is between 4 and 8 mg/kg gas.
Commercializing black liquor and biomass gasifier/ gas turbine technology
96lQ2306
Larson, E. D. and Raymond, D. R. Tappi J., 1997, 80, (12), 50-57. As most existing powerhouses in the USA will require major rebuilding or replacement within the next 5-15 years, the prospects for the commercial introduction of black liquor and biomass gasification/combined cycle technologies (BLGCC and GGCC) into US Mills are very favourable. GCC systems would provide multiple benefits, for example, the US industry would gain technological leadership in the powerhouse area and powerhouse environmental performance would be enhanced at lower levels of capital investment. Several equipment developers are pursuing development of black liquor and biomass gasification technologies and recent efforts have brought several technologies successfully to pilot scale. All that remains is to verify the technology at a commercial level. Successful commercialization will mean the availability of a revolutionary new class of powerhouse technologies. To this end, an alliance of paper companies is being pursued to work with the government to fund the demonstration programme needed to make the technology ready commercially. 96102307
Effect of pressure transducer position on measured cylinder pressure diagram of high speed diesel engines Hountalas, D. T. and Anestis, A. Energy Comers. Mgmt, 1998, 39, (7), 589-607. If processed, the cylinder pressure diagram is a valuable source of information for reciprocating internal combustion engines, providing information concerning the combustion process inside the engine cylinder. A problem that usually arises during this process is the proper mounting of the pressure sensor on the cylinder head. The optimum is to flush-mount the transducer to the cylinder head so that it can be directly in contact with the gas. In many cases this is unfortunately not always possible, so the engineer must position the transducer in a location away from the cylinder head to bring it to continuous contact with the cylinder gas through a duct. Experiments reveal this may result in errors in the measured values of the gas pressure that differ from the actual ones inside the combustion chamber. In the case of spark ignition engines, pressure sensors are
Takao, S. et al. Jpn. Kokai Tokkyo Koho JP 09,303,158 [97,303,158] (Cl. F02C3128). 25 Nov 1997, Appl. 961141,033, 10 May 1996, 6 pp. (In Japanese) The method comprises cooling the gas containing SO, and alkali metal vapours generated from a pressurized coal partial combustor to 550-1100°C by passing to a gas cooler. A high-temperature dust-collection apparatus is used for dedusting and the dedusted gas is introduced into an alkali metalremoval apparatus filled with alkali metal-removal agents for the removal of alkali metal vapours and mist. The resultant gas is introduced into a gas turbine for combustion. The alkali metal-removal agents contain AlzOs and SiOz.
96lO2316 Method and apparatus for dividing and feeding fuel gases to fuel cell and turbine Noelscher, C. and Suchy, P. Ger. Offen. DE 19,535,288 (Cl. F02C3/28), 27 Mar 1997, Appl. 19,535,288, 22 Sep 1995, 7 pp. (In German) Obtained by reforming natural gas or by gasification of coal, wastes, etc., the fuel gases are led into a purification unit and then through a hydrogenseparation unit. The separated hydrogen is subsequently led into a hydrogen-oxygen fuel cell and the cobalt-containing part of the fuel gases is supplied to the turbine. 96io2311 MILP optimization of a CHP energy system BojiC, M. and Stojanovic, B. Energy Convers. Mgmt, 1998, 39, (7), 637-642. Heat and power consumed by a factory to support its technology can be produced inside the factory or bought from an outside plant. A CHP energy system consisting of a steam boiler and a backpressure turbine is used to produce these energies. Using a steady-state, bottom-up approach, a network of energy modules and mixed integer linear programming (MILP), a software package-KOM9-has been developed. Depending on the unit costs of different kinds of energies, the cost region diagram was derived. This diagram gives an energy plant operator a recommendation for the use of an optimum energy consumption of particular composition. This yields the minimum energy expense and, at most, 65.6% in cost saving. Despite inexpensive production of the power, it is shown that sometimes it may not be optimal to operate the turbine. This is the case when refuse steam for heating purposes is available.
96102312 Next-generation integration separation units and gas turbines
concepts
for air
Smith, A. R. ef al. J. Eng. Gas Turbines Power, 1997, 119, (2), 298-304. Concepts involving the integration of a cryogenic air separation unit (ASU) with the gas turbine combined-cycle module have aided the commercialization of integrated gasification combined cycle (IGCC) power. Other processes, such as coal-based ironmaking and combined power/industrial gas production facilities, can also benefit from the integration. A widely accepted concept is that of the ASU designed for ‘elevated pressure’ service and optimally integrated with the gas turbine can increase overall IGCC power output, increase overall efficiency and decrease the net cost of power generation in comparison with non-integrated facilities employing lowpressure ASUs. The specific gas turbine, gasification technology, NO, emission specification and other site specific factors determine the optimal degree of compressed air and nitrogen stream integration. Continuing advancements in both air separation and gas turbine technologies offer new integration opportunities to improve performance and reduce costs. The basic integration principles are reviewed and next-generation concepts based on advanced high pressure ratio gas turbines, humid air turbine (HAT) cycles and integration of compression heat and refrigeration sources from the ASU are the subject of discussion. Further evaluation is carried out on operability issues associated with integration and control measures for the safe, efficient and reliable operation of these facilities are discussed.
Fuel and Energy Abstracts
May 1996
209
conditions. The technique operates in inert environments to isolate the thermal deactivation mechanisms from possible oxidative mechanisms occurring in true combustion experiments. The technique, based on an inert-gas-purged, refractory-metal, high-temperature wire mesh, is demonstrated here on monomaceral-rich fractions from four parent coals of diverse origin. The results show that char reactivity is quite sensitive to preparation conditions in the range of interest to combustion, decreasing by a factor of 30-50 between 1000°C and 1800°C in only 2 s of treatment for seven of eight samples examined. The 1800°C chars have similar reactivities to boiler fly-ash chars measured previously, lending support for the thermal deactivation hypothesis. The results also show that thermal deactivation propensity is a function of precursor, with vitrinite-rich fractions deactivating more readily than inertinite-rich fractions. The propensity for deactivation is shown to correlate with the extent of crystal order development as observed by high-resolution TEM fringe imaging. The relationship between fuel chemistry and deactivation propensity, as well as the implications of the reactivity results for combustion processes are discussed in the paper.
10
Engines (power generation
and propulsion,
electrical vehicles)
mounted on the engine spark plug, but in Diesel engines, the transducer must be mounted separately. The main scope of the present work is to examine the effect of the transducer position on the measured pressure diagram in high speed diesel engines. For this purpose, in the present work, a theoretical investigation is conducted using a simulation model developed by the authors, where the unsteady flow problem in the connecting pipeline from the combustion chamber to the transducer is solved using a finite difference scheme. The operation of a high speed diesel engine at various conditions is simulated with a simple combustion model. The results reveal the limits within which the pressure measurements are reliable and may be possibly used to develop a method for correcting the measured pressure diagram.
Impact of energy efficient motors in the petrochemical industry F;_ele5r. K. F. and Pillay, P. Electric Power Systems Research, 1997, 42, (1)
96lO2306
An in-depth survey of moors in two chemical plants of similar size is reported. The energy and demand savings potential was determined and hence the dollar savings using a sliding rate structure currently applicable to the petrochemical industry in Louisiana. Energy and demand savings were determined with extensive use of the MotorMaster programme.
ENGINES Method and apparatus for coal direct combustion gas-turbine combined-cycle power generation with alkali metal vapor stripping
98/02309
Power Generation and Propulsion, Electrical Vehicles Alkali separation in steam injected cyclone wood powder gasifier for gas turbine application
96lo2305
Fredriksson, C. and Kjellstrom, B. Dev. Thermochem. Biomass Convers., A. V. and Boocock, D. G. B., 1997, 2, 921-931. Edited by Bridgwater, Blackie, London, UK. A study of cyclone gasification of wood powder at atmospheric pressure was conducted. The cyclone gasifier also works as a particle separator and the wood powder is injected into the cyclone with air or air or steam as the transport medium. The effects of stoichiometry and steam injection on the gasification temperature and separation of char particles were investigated, and the experimental results compared with theoretical predictions. The amount of potassium and sodium that can be separated together with the char was also studied since this is of special interest if the gas is used to operate a gas turbine. The fuel flow was 26 kg/h corresponding to a thermal input of 140 kW. The equivalence ratio varied from 0.15 and 0.4. Wood powder was injected with air only or air and steam with steam mass flows of 50-80% of the fuel flow. It has been possible to separate 20-40% of the potassium and lo-20% of the sodium supplied with the wood, and as a result the alkali content in the gas entering a turbine at a temperature of 850°C is between 4 and 8 mg/kg gas.
Commercializing black liquor and biomass gasifier/ gas turbine technology
96lQ2306
Larson, E. D. and Raymond, D. R. Tappi J., 1997, 80, (12), 50-57. As most existing powerhouses in the USA will require major rebuilding or replacement within the next 5-15 years, the prospects for the commercial introduction of black liquor and biomass gasification/combined cycle technologies (BLGCC and GGCC) into US Mills are very favourable. GCC systems would provide multiple benefits, for example, the US industry would gain technological leadership in the powerhouse area and powerhouse environmental performance would be enhanced at lower levels of capital investment. Several equipment developers are pursuing development of black liquor and biomass gasification technologies and recent efforts have brought several technologies successfully to pilot scale. All that remains is to verify the technology at a commercial level. Successful commercialization will mean the availability of a revolutionary new class of powerhouse technologies. To this end, an alliance of paper companies is being pursued to work with the government to fund the demonstration programme needed to make the technology ready commercially. 96102307
Effect of pressure transducer position on measured cylinder pressure diagram of high speed diesel engines Hountalas, D. T. and Anestis, A. Energy Comers. Mgmt, 1998, 39, (7), 589-607. If processed, the cylinder pressure diagram is a valuable source of information for reciprocating internal combustion engines, providing information concerning the combustion process inside the engine cylinder. A problem that usually arises during this process is the proper mounting of the pressure sensor on the cylinder head. The optimum is to flush-mount the transducer to the cylinder head so that it can be directly in contact with the gas. In many cases this is unfortunately not always possible, so the engineer must position the transducer in a location away from the cylinder head to bring it to continuous contact with the cylinder gas through a duct. Experiments reveal this may result in errors in the measured values of the gas pressure that differ from the actual ones inside the combustion chamber. In the case of spark ignition engines, pressure sensors are
Takao, S. et al. Jpn. Kokai Tokkyo Koho JP 09,303,158 [97,303,158] (Cl. F02C3128). 25 Nov 1997, Appl. 961141,033, 10 May 1996, 6 pp. (In Japanese) The method comprises cooling the gas containing SO, and alkali metal vapours generated from a pressurized coal partial combustor to 550-1100°C by passing to a gas cooler. A high-temperature dust-collection apparatus is used for dedusting and the dedusted gas is introduced into an alkali metalremoval apparatus filled with alkali metal-removal agents for the removal of alkali metal vapours and mist. The resultant gas is introduced into a gas turbine for combustion. The alkali metal-removal agents contain AlzOs and SiOz.
96lO2316 Method and apparatus for dividing and feeding fuel gases to fuel cell and turbine Noelscher, C. and Suchy, P. Ger. Offen. DE 19,535,288 (Cl. F02C3/28), 27 Mar 1997, Appl. 19,535,288, 22 Sep 1995, 7 pp. (In German) Obtained by reforming natural gas or by gasification of coal, wastes, etc., the fuel gases are led into a purification unit and then through a hydrogenseparation unit. The separated hydrogen is subsequently led into a hydrogen-oxygen fuel cell and the cobalt-containing part of the fuel gases is supplied to the turbine. 96io2311 MILP optimization of a CHP energy system BojiC, M. and Stojanovic, B. Energy Convers. Mgmt, 1998, 39, (7), 637-642. Heat and power consumed by a factory to support its technology can be produced inside the factory or bought from an outside plant. A CHP energy system consisting of a steam boiler and a backpressure turbine is used to produce these energies. Using a steady-state, bottom-up approach, a network of energy modules and mixed integer linear programming (MILP), a software package-KOM9-has been developed. Depending on the unit costs of different kinds of energies, the cost region diagram was derived. This diagram gives an energy plant operator a recommendation for the use of an optimum energy consumption of particular composition. This yields the minimum energy expense and, at most, 65.6% in cost saving. Despite inexpensive production of the power, it is shown that sometimes it may not be optimal to operate the turbine. This is the case when refuse steam for heating purposes is available.
96102312 Next-generation integration separation units and gas turbines
concepts
for air
Smith, A. R. ef al. J. Eng. Gas Turbines Power, 1997, 119, (2), 298-304. Concepts involving the integration of a cryogenic air separation unit (ASU) with the gas turbine combined-cycle module have aided the commercialization of integrated gasification combined cycle (IGCC) power. Other processes, such as coal-based ironmaking and combined power/industrial gas production facilities, can also benefit from the integration. A widely accepted concept is that of the ASU designed for ‘elevated pressure’ service and optimally integrated with the gas turbine can increase overall IGCC power output, increase overall efficiency and decrease the net cost of power generation in comparison with non-integrated facilities employing lowpressure ASUs. The specific gas turbine, gasification technology, NO, emission specification and other site specific factors determine the optimal degree of compressed air and nitrogen stream integration. Continuing advancements in both air separation and gas turbine technologies offer new integration opportunities to improve performance and reduce costs. The basic integration principles are reviewed and next-generation concepts based on advanced high pressure ratio gas turbines, humid air turbine (HAT) cycles and integration of compression heat and refrigeration sources from the ASU are the subject of discussion. Further evaluation is carried out on operability issues associated with integration and control measures for the safe, efficient and reliable operation of these facilities are discussed.
Fuel and Energy Abstracts
May 1996
209