1995
Informes técnicos
Bilbao, Rafael; Alzueta, María U; Millera, Ángela; Duarte, Mario
Simplified Kinetic Model of the Chemistry in the Reburning Zone Using Natural Gas Informe técnico
1995.
@techreport{Bilbao1995c,
title = {Simplified Kinetic Model of the Chemistry in the Reburning Zone Using Natural Gas},
author = {Rafael Bilbao and María U Alzueta and Ángela Millera and Mario Duarte},
url = {https://pubs.acs.org/sharingguidelines},
year = {1995},
date = {1995-01-01},
booktitle = {Ind. Eng. Chem. Res},
volume = {34},
pages = {4540--4548},
abstract = {A simplified kinetic model of the chemistry of NO reduction by the action of natural gas has been obtained. This model consists of 87 elementary reactions and 38 chemical species. It takes into account the natural gas decomposition and oxidation, the interaction between NO and hydrocarbons, and the conversion of the intermediate nitrogenous species. The concentrations of the species calculated with the model have been compared with those obtained experimentally using the operating conditions for which a good efficiency in the rebuming zone is achieved. The comparison between the theoretical and experimental data of NO, HCN, CO, and CO2 has been extended to the results obtained over a wide range of values of the operating conditions in the reburning zone.},
keywords = {},
pubstate = {published},
tppubtype = {techreport}
}
A simplified kinetic model of the chemistry of NO reduction by the action of natural gas has been obtained. This model consists of 87 elementary reactions and 38 chemical species. It takes into account the natural gas decomposition and oxidation, the interaction between NO and hydrocarbons, and the conversion of the intermediate nitrogenous species. The concentrations of the species calculated with the model have been compared with those obtained experimentally using the operating conditions for which a good efficiency in the rebuming zone is achieved. The comparison between the theoretical and experimental data of NO, HCN, CO, and CO2 has been extended to the results obtained over a wide range of values of the operating conditions in the reburning zone.
1994
Artículos de revista
Bilbao, Rafael; Salvador, María L; Arauzo, Jesús
Influence of the heating rate on the temperature profiles and on the conversion rate of powdery cellulose and pine sawdust Artículo de revista
En: Journal of Analytical and Applied Pyrolysis, vol. 30, no 2, pp. 145–159, 1994, ISSN: 01652370.
@article{Bilbao1994,
title = {Influence of the heating rate on the temperature profiles and on the conversion rate of powdery cellulose and pine sawdust},
author = {Rafael Bilbao and María L Salvador and Jesús Arauzo},
doi = {10.1016/0165-2370(94)00809-4},
issn = {01652370},
year = {1994},
date = {1994-12-01},
journal = {Journal of Analytical and Applied Pyrolysis},
volume = {30},
number = {2},
pages = {145--159},
publisher = {Elsevier},
abstract = {An experimental study of the thermal decomposition of powdered cellulose and pine sawdust has been performed. The influence of the heating rate on the temperature profiles in the sample and on the solid conversion rate has been studied. A mathematical model without adjustable parameters has been used to calculate the temperature at different points in the solid bed and the average total solid conversion. The experimental results have been compared with those calculated by the model. A good agreement has been obtained for sawdust. Some differences are observed for cellulose at high heating rates, and the influence of the thermal conductivity and the reaction heat on the results has been analysed. textcopyright 1994.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
An experimental study of the thermal decomposition of powdered cellulose and pine sawdust has been performed. The influence of the heating rate on the temperature profiles in the sample and on the solid conversion rate has been studied. A mathematical model without adjustable parameters has been used to calculate the temperature at different points in the solid bed and the average total solid conversion. The experimental results have been compared with those calculated by the model. A good agreement has been obtained for sawdust. Some differences are observed for cellulose at high heating rates, and the influence of the thermal conductivity and the reaction heat on the results has been analysed. textcopyright 1994.
Bilbao, Rafael; Millera, Ángela; Alzueta, María U
Influence of the Temperature and Oxygen Concentration on NOx Reduction in the Natural Gas Reburning Process Artículo de revista
En: Industrial and Engineering Chemistry Research, vol. 33, no 11, pp. 2846–2852, 1994, ISSN: 15205045.
@article{Bilbao1994a,
title = {Influence of the Temperature and Oxygen Concentration on NOx Reduction in the Natural Gas Reburning Process},
author = {Rafael Bilbao and Ángela Millera and María U Alzueta},
url = {https://pubs.acs.org/sharingguidelines},
doi = {10.1021/ie00035a039},
issn = {15205045},
year = {1994},
date = {1994-11-01},
journal = {Industrial and Engineering Chemistry Research},
volume = {33},
number = {11},
pages = {2846--2852},
publisher = {American Chemical Society},
abstract = {The reburning process with natural gas is an effective technique which can be applied in existing coal combustors in order to reduce the NOx emissions. The influence of the reburning temperature (1200–1500 °C) and the oxygen concentration coming from the primary combustion zone (0–5%) have been studied. Experimental results of NO, HCN, NH3, CO, CO2, and CH4 concentrations in the exit gas have been determined. The influence of the natural gas decomposition on these results has been analyzed. The experimental trends obtained have been compared with those calculated with the model of Kilpinen et al. (1992). textcopyright 1994, American Chemical Society. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The reburning process with natural gas is an effective technique which can be applied in existing coal combustors in order to reduce the NOx emissions. The influence of the reburning temperature (1200–1500 °C) and the oxygen concentration coming from the primary combustion zone (0–5%) have been studied. Experimental results of NO, HCN, NH3, CO, CO2, and CH4 concentrations in the exit gas have been determined. The influence of the natural gas decomposition on these results has been analyzed. The experimental trends obtained have been compared with those calculated with the model of Kilpinen et al. (1992). textcopyright 1994, American Chemical Society. All rights reserved.
Arauzo, Jesús; Radlein, D; Piskorz, J; Scott, D S
A New Catalyst for the Catalytic Gasification of Biomass Artículo de revista
En: Energy and Fuels, vol. 8, no 6, pp. 1192–1196, 1994, ISSN: 15205029.
@article{Arauzo1994,
title = {A New Catalyst for the Catalytic Gasification of Biomass},
author = {Jesús Arauzo and D Radlein and J Piskorz and D S Scott},
url = {https://pubs.acs.org/sharingguidelines},
doi = {10.1021/ef00048a005},
issn = {15205029},
year = {1994},
date = {1994-11-01},
journal = {Energy and Fuels},
volume = {8},
number = {6},
pages = {1192--1196},
publisher = {American Chemical Society},
abstract = {Various kinds of catalysts are being developed and tested for the pyrolytic gasification of biomass using the Waterloo Fast Pyrolysis Process (WFPP) technology. The present report describes gasification tests with wood in a continuous bench scale fluidized bed reactor but with no added air or oxygen in the region of 500–700 °C and at short gas contact times, using a crystalline nickel aluminate catalyst. The objective was to determine the most appropriate operating conditions for this catalyst and its performance for the production of a synthesis gas in high yields. Experiments were carried out with this catalyst in both inert and reactive gasification media, but without any oxygen or air addition. The results show the influence of the catalyst on the nature of the gasification products and the effect of operating variables. Gas compositions are given for typical WFPP operating conditions. Evidence is presented which indicates that the gasification mechanism is a fast thermal pyrolysis followed by catalytic reforming of the vapors with a high yield of synthesis gas. textcopyright 1994, American Chemical Society. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Various kinds of catalysts are being developed and tested for the pyrolytic gasification of biomass using the Waterloo Fast Pyrolysis Process (WFPP) technology. The present report describes gasification tests with wood in a continuous bench scale fluidized bed reactor but with no added air or oxygen in the region of 500–700 °C and at short gas contact times, using a crystalline nickel aluminate catalyst. The objective was to determine the most appropriate operating conditions for this catalyst and its performance for the production of a synthesis gas in high yields. Experiments were carried out with this catalyst in both inert and reactive gasification media, but without any oxygen or air addition. The results show the influence of the catalyst on the nature of the gasification products and the effect of operating variables. Gas compositions are given for typical WFPP operating conditions. Evidence is presented which indicates that the gasification mechanism is a fast thermal pyrolysis followed by catalytic reforming of the vapors with a high yield of synthesis gas. textcopyright 1994, American Chemical Society. All rights reserved.
García-Bacaicoa, Pedro; Bilbao, Rafael; Arauzo, Jesús; Salvador, María L
Scale-up of downdraft moving bed gasifiers (25-300 kg/h) – Design, experimental aspects and results Artículo de revista
En: Bioresource Technology, vol. 48, no 3, pp. 229–235, 1994, ISSN: 09608524.
@article{Garcia-Bacaicoa1994,
title = {Scale-up of downdraft moving bed gasifiers (25-300 kg/h) - Design, experimental aspects and results},
author = {Pedro García-Bacaicoa and Rafael Bilbao and Jesús Arauzo and María L Salvador},
doi = {10.1016/0960-8524(94)90151-1},
issn = {09608524},
year = {1994},
date = {1994-01-01},
journal = {Bioresource Technology},
volume = {48},
number = {3},
pages = {229--235},
publisher = {Elsevier},
abstract = {Two installations with different biomass processing capacities (25-50 and 200-300 kg/h) were designed and constructed for air gasification of lignocellulosic biomass. This paper describes both installations as well as the experimental procedure. The influence of operating conditions on the amount and quality of products was determined. The results obtained from processing forestry waste are analysed. Values above 90% for mass conversion efficiency and over 70% for cold gas efficiency were reached. textcopyright 1994.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Two installations with different biomass processing capacities (25-50 and 200-300 kg/h) were designed and constructed for air gasification of lignocellulosic biomass. This paper describes both installations as well as the experimental procedure. The influence of operating conditions on the amount and quality of products was determined. The results obtained from processing forestry waste are analysed. Values above 90% for mass conversion efficiency and over 70% for cold gas efficiency were reached. textcopyright 1994.
1993
Artículos de revista
Bilbao, Rafael; Salvador, María L; García-Bacaicoa, Pedro; Arauzo, Jesús
Solid weight loss in the thermal decomposition of cellulose and pine sawdust Artículo de revista
En: Journal of Analytical and Applied Pyrolysis, vol. 24, no 3, pp. 257–271, 1993, ISSN: 01652370.
@article{Bilbao1993a,
title = {Solid weight loss in the thermal decomposition of cellulose and pine sawdust},
author = {Rafael Bilbao and María L Salvador and Pedro García-Bacaicoa and Jesús Arauzo},
doi = {10.1016/0165-2370(93)85005-J},
issn = {01652370},
year = {1993},
date = {1993-02-01},
journal = {Journal of Analytical and Applied Pyrolysis},
volume = {24},
number = {3},
pages = {257--271},
publisher = {Elsevier},
abstract = {An experimental study of the thermal decomposition of powdered lignocellulosic biomass was performed in a macrobalance system. Weight loss and temperature profiles in the bed for different heating rates were determined using mainly cellulose and pine sawdust. Some experiments with xylan and lignin were also carried out. A simple model was used to calculate weight loss and temperature at different points. An average temperature allows comparison of the results obtained. textcopyright 1993.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
An experimental study of the thermal decomposition of powdered lignocellulosic biomass was performed in a macrobalance system. Weight loss and temperature profiles in the bed for different heating rates were determined using mainly cellulose and pine sawdust. Some experiments with xylan and lignin were also carried out. A simple model was used to calculate weight loss and temperature at different points. An average temperature allows comparison of the results obtained. textcopyright 1993.
Bilbao, Rafael; Millera, Ángela; Murillo, María Benita
Temperature Profiles and Weight Loss in the Thermal Decomposition of Large Spherical Wood Particles Artículo de revista
En: Industrial and Engineering Chemistry Research, vol. 32, no 9, pp. 1811–1817, 1993, ISSN: 15205045.
@article{Bilbao1993,
title = {Temperature Profiles and Weight Loss in the Thermal Decomposition of Large Spherical Wood Particles},
author = {Rafael Bilbao and Ángela Millera and María Benita Murillo},
url = {https://pubs.acs.org/sharingguidelines},
doi = {10.1021/ie00021a003},
issn = {15205045},
year = {1993},
date = {1993-01-01},
journal = {Industrial and Engineering Chemistry Research},
volume = {32},
number = {9},
pages = {1811--1817},
publisher = {American Chemical Society},
abstract = {The thermal decomposition of relatively large particles of pine wood has been studied. By use of spherical particles of different sizes (2–5.6 cm in diameter), the experimental solid conversion values and the temperature at different points of the solid are analyzed for different heating rates of the system. The experimental results have been compared with those calculated with a simple model, which involves the solution of the heat and mass balances and the kinetic equations, using experimental values as boundary conditions. A good agreement has been obtained for particles up to 4 cm in diameter. For larger particles the mass transfer resistance inside the solid and the existence of secondary reactions may acquire an appreciable importance. textcopyright 1993, American Chemical Society. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The thermal decomposition of relatively large particles of pine wood has been studied. By use of spherical particles of different sizes (2–5.6 cm in diameter), the experimental solid conversion values and the temperature at different points of the solid are analyzed for different heating rates of the system. The experimental results have been compared with those calculated with a simple model, which involves the solution of the heat and mass balances and the kinetic equations, using experimental values as boundary conditions. A good agreement has been obtained for particles up to 4 cm in diameter. For larger particles the mass transfer resistance inside the solid and the existence of secondary reactions may acquire an appreciable importance. textcopyright 1993, American Chemical Society. All rights reserved.
1992
Artículos de revista
Bilbao, Rafael; Murillo, María Benita; Millera, Ángela
Angular and radial temperature profiles in the thermal decomposition of wood Artículo de revista
En: Thermochimica Acta, vol. 200, no C, pp. 401–411, 1992, ISSN: 00406031.
@article{Bilbao1992a,
title = {Angular and radial temperature profiles in the thermal decomposition of wood},
author = {Rafael Bilbao and María Benita Murillo and Ángela Millera},
doi = {10.1016/0040-6031(92)85133-G},
issn = {00406031},
year = {1992},
date = {1992-07-01},
journal = {Thermochimica Acta},
volume = {200},
number = {C},
pages = {401--411},
publisher = {Elsevier},
abstract = {During the thermal decomposition of wood, an increase in the particle size produces an important decrease in the weight loss of the solid caused by significant temperature profiles, both radial and angular, inside the solid. In order to determine these profiles, experiments with different particle sizes (2, 3, 4 and 5.6 cm in diameter) have been carried out. In these experiments, temperatures at different points corresponding to various values of radii and angles were measured. An analysis of the different values and trends obtained has been performed. textcopyright 1992.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
During the thermal decomposition of wood, an increase in the particle size produces an important decrease in the weight loss of the solid caused by significant temperature profiles, both radial and angular, inside the solid. In order to determine these profiles, experiments with different particle sizes (2, 3, 4 and 5.6 cm in diameter) have been carried out. In these experiments, temperatures at different points corresponding to various values of radii and angles were measured. An analysis of the different values and trends obtained has been performed. textcopyright 1992.
Bilbao, Rafael; Murillo, María Benita; Millera, Ángela; Arauzo, Jesús; Caleya, José María
Thermal decomposition of a wood particle. Temperature profiles on the solid surface Artículo de revista
En: Thermochimica Acta, vol. 197, no 2, pp. 431–442, 1992, ISSN: 00406031.
@article{Bilbao1992,
title = {Thermal decomposition of a wood particle. Temperature profiles on the solid surface},
author = {Rafael Bilbao and María Benita Murillo and Ángela Millera and Jesús Arauzo and José María Caleya},
doi = {10.1016/0040-6031(92)85044-V},
issn = {00406031},
year = {1992},
date = {1992-03-01},
journal = {Thermochimica Acta},
volume = {197},
number = {2},
pages = {431--442},
publisher = {Elsevier},
abstract = {The calculation of the weight loss during the thermal decomposition of lignocellulosic materials involves the solution of the heat and mass balance equations. In order to solve these equations it is necessary to know the temperature on the solid surface, which can vary at different points and can also be very different from the gas temperature. In this work, an experimental study was carried out in a system which allows the use of large particle sizes and the simulation of different operating conditions. In this study, the temperatures on the solid surface were measured and compared with those corresponding to the empty reactor. textcopyright 1992.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The calculation of the weight loss during the thermal decomposition of lignocellulosic materials involves the solution of the heat and mass balance equations. In order to solve these equations it is necessary to know the temperature on the solid surface, which can vary at different points and can also be very different from the gas temperature. In this work, an experimental study was carried out in a system which allows the use of large particle sizes and the simulation of different operating conditions. In this study, the temperatures on the solid surface were measured and compared with those corresponding to the empty reactor. textcopyright 1992.
1991
Artículos de revista
Bilbao, Rafael; Murillo, María Benita; Millera, Ángela; Mastral, José Francisco
Thermal decomposition of lignocellulosic materials: comparison of the results obtained in different experimental systems Artículo de revista
En: Thermochimica Acta, vol. 190, no 2, pp. 163–173, 1991, ISSN: 00406031.
@article{Bilbao1991a,
title = {Thermal decomposition of lignocellulosic materials: comparison of the results obtained in different experimental systems},
author = {Rafael Bilbao and María Benita Murillo and Ángela Millera and José Francisco Mastral},
doi = {10.1016/0040-6031(91)85242-A},
issn = {00406031},
year = {1991},
date = {1991-11-01},
journal = {Thermochimica Acta},
volume = {190},
number = {2},
pages = {163--173},
publisher = {Elsevier},
abstract = {An experimental system that allows the use of large particle sizes and the simulation of different operating conditions was built to study the thermal decomposition of lignocellulosic materials. The values of solid conversion and of temperature obtained at different points using spherical particles of pine wood 2 cm in diameter are shown. The conversion values are compared with those calculated from the equations obtained in a thermobalance for small particle sizes. textcopyright 1991.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
An experimental system that allows the use of large particle sizes and the simulation of different operating conditions was built to study the thermal decomposition of lignocellulosic materials. The values of solid conversion and of temperature obtained at different points using spherical particles of pine wood 2 cm in diameter are shown. The conversion values are compared with those calculated from the equations obtained in a thermobalance for small particle sizes. textcopyright 1991.
Bilbao, Rafael; Lezaun, J; Menéndez, Miguel; Izquierdo, Marı́a Teresa
Segregation of straw/sand mixtures in fluidized beds in non-steady state Artículo de revista
En: Powder Technology, vol. 68, no 1, pp. 31–35, 1991, ISSN: 00325910.
@article{Bilbao1991,
title = {Segregation of straw/sand mixtures in fluidized beds in non-steady state},
author = {Rafael Bilbao and J Lezaun and Miguel Menéndez and Marı́a Teresa Izquierdo},
doi = {10.1016/0032-5910(91)80061-M},
issn = {00325910},
year = {1991},
date = {1991-10-01},
journal = {Powder Technology},
volume = {68},
number = {1},
pages = {31--35},
publisher = {Elsevier},
abstract = {A model predicting the concentration profiles of straw/sand mixtures in non-steady-state fluidized beds is presented. The model is based on the mechanisms of mixing-segregation developed for these mixtures in steady state. A method to solve the mass balances is shown. Satisfactory agreement is obtained between the experimental results and the predictions of the model. The variation of mixing index with the time is also shown. textcopyright 1991.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
A model predicting the concentration profiles of straw/sand mixtures in non-steady-state fluidized beds is presented. The model is based on the mechanisms of mixing-segregation developed for these mixtures in steady state. A method to solve the mass balances is shown. Satisfactory agreement is obtained between the experimental results and the predictions of the model. The variation of mixing index with the time is also shown. textcopyright 1991.
1990
Artículos de revista
Bilbao, Rafael; Millera, Ángela; Arauzo, Jesús
Kinetics of weight loss by thermal decomposition of different lignocellulosic materials. Relation between the results obtained from isothermal and dynamic experiments Artículo de revista
En: Thermochimica Acta, vol. 165, no 1, pp. 103–112, 1990, ISSN: 00406031.
@article{Bilbao1990,
title = {Kinetics of weight loss by thermal decomposition of different lignocellulosic materials. Relation between the results obtained from isothermal and dynamic experiments},
author = {Rafael Bilbao and Ángela Millera and Jesús Arauzo},
doi = {10.1016/0040-6031(90)80210-P},
issn = {00406031},
year = {1990},
date = {1990-07-01},
journal = {Thermochimica Acta},
volume = {165},
number = {1},
pages = {103--112},
publisher = {Elsevier},
abstract = {The kinetics of weight loss in the thermal decomposition of Pinaster pine and barley straw in a nitrogen environment have been studied. The results obtained under different experimental conditions are shown and compared. These results are related by using the results of dynamic experiments with low heating rates as a reference. textcopyright 1990.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The kinetics of weight loss in the thermal decomposition of Pinaster pine and barley straw in a nitrogen environment have been studied. The results obtained under different experimental conditions are shown and compared. These results are related by using the results of dynamic experiments with low heating rates as a reference. textcopyright 1990.
1989
Artículos de revista
Bilbao, Rafael; Millera, Ángela; Arauzo, Jesús
Kinetics of weight loss by thermal decomposition of xylan and lignin. Influence of experimental conditions Artículo de revista
En: Thermochimica Acta, vol. 143, no C, pp. 137–148, 1989, ISSN: 00406031.
@article{Bilbao1989,
title = {Kinetics of weight loss by thermal decomposition of xylan and lignin. Influence of experimental conditions},
author = {Rafael Bilbao and Ángela Millera and Jesús Arauzo},
doi = {10.1016/0040-6031(89)85051-8},
issn = {00406031},
year = {1989},
date = {1989-05-01},
journal = {Thermochimica Acta},
volume = {143},
number = {C},
pages = {137--148},
publisher = {Elsevier},
abstract = {The kinetics of weight loss in the thermal decomposition of xylan and lignin in a nitrogen environment have been studied thermogravimetrically. The data from this study are analysed in the light of previous conclusions obtained with cellulose. The results from isothermal and dynamic experiments at different heating rates are related by using the results of dynamic experiments with low heating rates (1.5 °C min-1) as a reference. textcopyright 1989.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The kinetics of weight loss in the thermal decomposition of xylan and lignin in a nitrogen environment have been studied thermogravimetrically. The data from this study are analysed in the light of previous conclusions obtained with cellulose. The results from isothermal and dynamic experiments at different heating rates are related by using the results of dynamic experiments with low heating rates (1.5 °C min-1) as a reference. textcopyright 1989.
Bilbao, Rafael; Millera, Ángela; Arauzo, Jesús
Thermal decomposition of lignocellulosic materials: influence of the chemical composition Artículo de revista
En: Thermochimica Acta, vol. 143, no C, pp. 149–159, 1989, ISSN: 00406031.
@article{Bilbao1989a,
title = {Thermal decomposition of lignocellulosic materials: influence of the chemical composition},
author = {Rafael Bilbao and Ángela Millera and Jesús Arauzo},
doi = {10.1016/0040-6031(89)85052-X},
issn = {00406031},
year = {1989},
date = {1989-05-01},
journal = {Thermochimica Acta},
volume = {143},
number = {C},
pages = {149--159},
publisher = {Elsevier},
abstract = {The results obtained with different lignocellulosic materials ("Pinaster" pine and barley straw) are compared with those calculated by considering the weighted contributions of the different constituents of the materials. The results obtained in isothermal and dynamic experiments with "Pinaster" pine showed a good agreement, whereas higher divergences were found for barley straw. A different method of data analysis is proposed for barley straw, which uses results directly obtained with this material. textcopyright 1989.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The results obtained with different lignocellulosic materials (“Pinaster” pine and barley straw) are compared with those calculated by considering the weighted contributions of the different constituents of the materials. The results obtained in isothermal and dynamic experiments with “Pinaster” pine showed a good agreement, whereas higher divergences were found for barley straw. A different method of data analysis is proposed for barley straw, which uses results directly obtained with this material. textcopyright 1989.
1988
Artículos de revista
Bilbao, Rafael; Lezaun, J; Menéndez, Miguel; Abanades, J C
Model of mixing-segregation for straw/sand mixtures in fluidized beds Artículo de revista
En: Powder Technology, vol. 56, no 3, pp. 149–155, 1988, ISSN: 00325910.
@article{Bilbao1988,
title = {Model of mixing-segregation for straw/sand mixtures in fluidized beds},
author = {Rafael Bilbao and J Lezaun and Miguel Menéndez and J C Abanades},
doi = {10.1016/0032-5910(88)80026-3},
issn = {00325910},
year = {1988},
date = {1988-11-01},
journal = {Powder Technology},
volume = {56},
number = {3},
pages = {149--155},
publisher = {Elsevier},
abstract = {When a sand/straw mixture (HSF/LBP type) is fluidized with air, a high degree of segregation can appear, with the sand settling at the bottom of the bed (jetsam) and the straw rising to the top (flotsam). A new model, based on that of Gibilaro and Rowe but accounting for the particular characteristics of the solids used, has been developed. Reasonable agreement with experimental data has been obtained. The values of the parameters that fit the experimental results for a wide range of conditions are obtained. textcopyright 1988.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
When a sand/straw mixture (HSF/LBP type) is fluidized with air, a high degree of segregation can appear, with the sand settling at the bottom of the bed (jetsam) and the straw rising to the top (flotsam). A new model, based on that of Gibilaro and Rowe but accounting for the particular characteristics of the solids used, has been developed. Reasonable agreement with experimental data has been obtained. The values of the parameters that fit the experimental results for a wide range of conditions are obtained. textcopyright 1988.
Bilbao, Rafael; Millera, Ángela; Arauzo, Jesús
Product distribution in the flash pyrolysis of lignocellulosic materials in a fluidized bed Artículo de revista
En: Fuel, vol. 67, no 11, pp. 1586–1588, 1988, ISSN: 00162361.
@article{Bilbao1988a,
title = {Product distribution in the flash pyrolysis of lignocellulosic materials in a fluidized bed},
author = {Rafael Bilbao and Ángela Millera and Jesús Arauzo},
doi = {10.1016/0016-2361(88)90082-8},
issn = {00162361},
year = {1988},
date = {1988-11-01},
journal = {Fuel},
volume = {67},
number = {11},
pages = {1586--1588},
publisher = {Elsevier},
abstract = {Knowledge of the flash pyrolysis of lignocellulosic materials is of great importance because it constitutes the first step of several thermochemical processes. This work is concerned with the study of the products obtained when the pyrolysis of lignocellulosic materials is carried out in a fluidized bed reactor. Two different feeds have been used, namely, wheat straw and pine sawdust. The proportions of gas, liquid and solids in the product as well as the composition of the exit gas have been obtained for different operating conditions. textcopyright 1988.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Knowledge of the flash pyrolysis of lignocellulosic materials is of great importance because it constitutes the first step of several thermochemical processes. This work is concerned with the study of the products obtained when the pyrolysis of lignocellulosic materials is carried out in a fluidized bed reactor. Two different feeds have been used, namely, wheat straw and pine sawdust. The proportions of gas, liquid and solids in the product as well as the composition of the exit gas have been obtained for different operating conditions. textcopyright 1988.
1987
Artículos de revista
Bilbao, Rafael; Arauzo, Jesús; Millera, Ángela
Kinetics of thermal decomposition of cellulose. Part I. Influence of experimental conditions Artículo de revista
En: Thermochimica Acta, vol. 120, no C, pp. 121–131, 1987, ISSN: 00406031.
@article{Bilbao1987,
title = {Kinetics of thermal decomposition of cellulose. Part I. Influence of experimental conditions},
author = {Rafael Bilbao and Jesús Arauzo and Ángela Millera},
doi = {10.1016/0040-6031(87)80211-3},
issn = {00406031},
year = {1987},
date = {1987-10-01},
journal = {Thermochimica Acta},
volume = {120},
number = {C},
pages = {121--131},
publisher = {Elsevier},
abstract = {The kinetics of weight loss in the thermal decomposition of cellulose have been determined by means of isothermal and dynamic experiments carried out under various conditions. Values for the pyrolyzable fraction, reaction order and kinetic constant have been obtained from isothermal experiments, while the important influence of the rate of heating of the system as well as the percentages of pyrolyzed solids at T ≤ 150°C have been observed from the dynamic experiments. textcopyright 1987.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The kinetics of weight loss in the thermal decomposition of cellulose have been determined by means of isothermal and dynamic experiments carried out under various conditions. Values for the pyrolyzable fraction, reaction order and kinetic constant have been obtained from isothermal experiments, while the important influence of the rate of heating of the system as well as the percentages of pyrolyzed solids at T ≤ 150°C have been observed from the dynamic experiments. textcopyright 1987.
Bilbao, Rafael; Arauzo, Jesús; Millera, Ángela
Kinetics of thermal decomposition of cellulose. Part II. Temperature differences between gas and solid at high heating rates Artículo de revista
En: Thermochimica Acta, vol. 120, no C, pp. 133–141, 1987, ISSN: 00406031.
@article{Bilbao1987a,
title = {Kinetics of thermal decomposition of cellulose. Part II. Temperature differences between gas and solid at high heating rates},
author = {Rafael Bilbao and Jesús Arauzo and Ángela Millera},
doi = {10.1016/0040-6031(87)80212-5},
issn = {00406031},
year = {1987},
date = {1987-10-01},
journal = {Thermochimica Acta},
volume = {120},
number = {C},
pages = {133--141},
publisher = {Elsevier},
abstract = {The use of high heating rates when studying the thermal decomposition kinetics of cellulose gives rise to a gap between the solid temperature and the thermogravimetric system temperature. A model is proposed which accounts for this temperature gap and permits the calculation of the actual solid temperature. The results for various heating rates are fitted using the same kinetic equation. textcopyright 1987.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The use of high heating rates when studying the thermal decomposition kinetics of cellulose gives rise to a gap between the solid temperature and the thermogravimetric system temperature. A model is proposed which accounts for this temperature gap and permits the calculation of the actual solid temperature. The results for various heating rates are fitted using the same kinetic equation. textcopyright 1987.
0000
Artículos de revista
Tran, Luc Sy; Carstensen, Hans-Heinrich; Foo, Kae Ken; Lamoureux, Nathalie; Gosselin, Sylvie; Gasnot, Laurent; El-Bakali, Abderrahman; Desgroux, Pascale
Experimental and modeling study of the high-temperature combustion chemistry of tetrahydrofurfuryl alcohol Artículo de revista
En: Proceedings of the Combustion Institute, vol. 38, no 1, pp. 631-640, 0000, ISSN: 15407489.
@article{Tran2020,
title = {Experimental and modeling study of the high-temperature combustion chemistry of tetrahydrofurfuryl alcohol},
author = {Luc Sy Tran and Hans-Heinrich Carstensen and Kae Ken Foo and Nathalie Lamoureux and Sylvie Gosselin and Laurent Gasnot and Abderrahman El-Bakali and Pascale Desgroux},
doi = {10.1016/j.proci.2020.07.057},
issn = {15407489},
urldate = {2020-09-01},
journal = {Proceedings of the Combustion Institute},
volume = {38},
number = {1},
pages = {631-640},
publisher = {Elsevier Ltd},
abstract = {Lignocellulosic tetrahydrofuranic (THF) biofuels have been identified as promising fuel candidates for spark-ignition (SI) engines. To support the potential use as transportation biofuels, fundamental studies of their combustion and emission behavior are highly important. In the present study, the high-temperature (HT) combustion chemistry of tetrahydrofurfuryl alcohol (THFA), a THF based biofuel, was investigated using a comprehensive experimental and numerical approach. Representative chemical species profiles in a stoichiometric premixed methane flame doped with $sim$20% (molar) THFA at 5.3 kPa were measured using online gas chromatography. The flame temperature was obtained by NO laser-induced fluorescence (LIF) thermometry. More than 40 chemical products were identified and quantified. Many of them such as ethylene, formaldehyde, acrolein, allyl alcohol, 2,3-dihydrofuran, 3,4-dihydropyran, 4-pentenal, and tetrahydrofuran-2-carbaldehyde are fuel-specific decomposition products formed in rather high concentrations. In the numerical part, as a complement to kinetic modeling, high-level theoretical calculations were performed to identify plausible reaction pathways that lead to the observed products. Furthermore, the rate coefficients of important reactions and the thermochemical properties of the related species were calculated. A detailed kinetic model for high-temperature combustion of THFA was developed, which reasonably predicts the experimental data. Subsequent rate analysis showed that THFA is mainly consumed by H-abstraction reactions yielding several fuel radicals that in turn undergo either $beta$-scission reactions or intramolecular radical addition that effectively leads to ring enlargement. The importance of specific reaction channels generally correlates with bond dissociation energies. Along THFA reaction routes, the derived species with cis configuration were found to be thermodynamically more stable than their corresponding trans configuration, which differs from usual observations for hydrocarbons.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Lignocellulosic tetrahydrofuranic (THF) biofuels have been identified as promising fuel candidates for spark-ignition (SI) engines. To support the potential use as transportation biofuels, fundamental studies of their combustion and emission behavior are highly important. In the present study, the high-temperature (HT) combustion chemistry of tetrahydrofurfuryl alcohol (THFA), a THF based biofuel, was investigated using a comprehensive experimental and numerical approach. Representative chemical species profiles in a stoichiometric premixed methane flame doped with $sim$20% (molar) THFA at 5.3 kPa were measured using online gas chromatography. The flame temperature was obtained by NO laser-induced fluorescence (LIF) thermometry. More than 40 chemical products were identified and quantified. Many of them such as ethylene, formaldehyde, acrolein, allyl alcohol, 2,3-dihydrofuran, 3,4-dihydropyran, 4-pentenal, and tetrahydrofuran-2-carbaldehyde are fuel-specific decomposition products formed in rather high concentrations. In the numerical part, as a complement to kinetic modeling, high-level theoretical calculations were performed to identify plausible reaction pathways that lead to the observed products. Furthermore, the rate coefficients of important reactions and the thermochemical properties of the related species were calculated. A detailed kinetic model for high-temperature combustion of THFA was developed, which reasonably predicts the experimental data. Subsequent rate analysis showed that THFA is mainly consumed by H-abstraction reactions yielding several fuel radicals that in turn undergo either $beta$-scission reactions or intramolecular radical addition that effectively leads to ring enlargement. The importance of specific reaction channels generally correlates with bond dissociation energies. Along THFA reaction routes, the derived species with cis configuration were found to be thermodynamically more stable than their corresponding trans configuration, which differs from usual observations for hydrocarbons.
Mergulhão, Carolina S; Carstensen, Hans-Heinrich; Song, Hwasup; Wagnon, Scott W; Pitz, William J; Vanhove, Guillaume
Probing the antiknock effect of anisole through an ignition, speciation and modeling study of its blends with isooctane Artículo de revista
En: Proceedings of the Combustion Institute, vol. 38, no 1, pp. 739-748, 0000, ISSN: 15407489.
@article{Mergulhao2020,
title = {Probing the antiknock effect of anisole through an ignition, speciation and modeling study of its blends with isooctane},
author = {Carolina S Mergulhão and Hans-Heinrich Carstensen and Hwasup Song and Scott W Wagnon and William J Pitz and Guillaume Vanhove},
doi = {10.1016/j.proci.2020.08.013},
issn = {15407489},
urldate = {2020-10-01},
journal = {Proceedings of the Combustion Institute},
volume = {38},
number = {1},
pages = {739-748},
publisher = {Elsevier Ltd},
abstract = {In order to unravel the reaction pathways relevant to anisole co-oxidation within a fuel blend, a detailed study of isooctane/anisole blends was performed with the ULille RCM. Ignition delays as well as mole fraction profiles were measured during a two-stage ignition delay using sampling and GC techniques. These results are used to validate a kinetic model developed from ab initio calculations for the most relevant rate constants which included H-atom abstraction reactions from anisole, and reactions on the potential energy surfaces of methoxyphenyl + O2 and anisyl + O2. Pressure dependent rate constants were computed for the methoxyphenyl + O2 and anisyl + O2 reactive systems using master equation code analysis. The new kinetic model shows good agreement with the experimental data. Dual brute-force sensitivity analysis was performed, on both first- and second-stages of ignition, allowing the identification of the most important reactions in the prediction of both ignition delays. It was observed that while pure anisole does not show NTC behavior, a 60/40 isooctane/anisole blend displays such behavior, as well as two-stage ignition. This suggests anisole addition may not be as beneficial to knock resistance as expected from its high octane number. The kinetic modeling results demonstrate the importance of H-abstraction reactions both from the methoxy group and from the aryl ring in ortho-position and the addition of the resultant radicals to O2, mostly leading to the formation of polar or non-aromatic products.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In order to unravel the reaction pathways relevant to anisole co-oxidation within a fuel blend, a detailed study of isooctane/anisole blends was performed with the ULille RCM. Ignition delays as well as mole fraction profiles were measured during a two-stage ignition delay using sampling and GC techniques. These results are used to validate a kinetic model developed from ab initio calculations for the most relevant rate constants which included H-atom abstraction reactions from anisole, and reactions on the potential energy surfaces of methoxyphenyl + O2 and anisyl + O2. Pressure dependent rate constants were computed for the methoxyphenyl + O2 and anisyl + O2 reactive systems using master equation code analysis. The new kinetic model shows good agreement with the experimental data. Dual brute-force sensitivity analysis was performed, on both first- and second-stages of ignition, allowing the identification of the most important reactions in the prediction of both ignition delays. It was observed that while pure anisole does not show NTC behavior, a 60/40 isooctane/anisole blend displays such behavior, as well as two-stage ignition. This suggests anisole addition may not be as beneficial to knock resistance as expected from its high octane number. The kinetic modeling results demonstrate the importance of H-abstraction reactions both from the methoxy group and from the aryl ring in ortho-position and the addition of the resultant radicals to O2, mostly leading to the formation of polar or non-aromatic products.