Documents disponibles écrits par cet auteur

High-temperature reaction in the freeboard region above a bubbling fluidized bed / Miloslav Hartman in Industrial & engineering chemistry research, Vol. 49 N° 6 (Mars 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp.2672–2680 Titre : High-temperature reaction in the freeboard region above a bubbling fluidized bed Type de document : texte imprimé Auteurs : Miloslav Hartman, Auteur ; Otakar Trnka, Auteur ; Michael Pohořelý, Auteur Année de publication : 2010 Article en page(s) : pp.2672–2680 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Temperature  Freeboard  Fluidized  Bed Résumé : A plug flow model is presented for the oxidation of hazardous carbon monoxide into inert carbon dioxide taking place in the freeboard region above a freely bubbling fluidized reactor. The extent of the reaction in oxygen- and water vapor-bearing flue gas is described as a function of the fraction of solids ejected into the freeboard from the bed surface, the relative throughput, the gas density, and the global rate of reaction. Experimental measurements were conducted to determine the axial concentration profiles of carbon monoxide and other species throughout the freeboard. Steady-state measurements were carried out in an electrically heated reactor with an inner diameter of 9.36 cm above a gently fluidized bed of heat-resistant ceramsite particles in which a precursive liguid fuel (isopropanol) was burned. The global burnout reaction is assumed to be first order in carbon monoxide and one-half order with respect to oxygen and water vapor. The rate parameters for CO and O2 reacting in the freeboard were determined from the measured concentration profiles. The numeric solutions of the model equations outline the possibilities and limitations for the performance of an afterburner chamber. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901760f [article] High-temperature reaction in the freeboard region above a bubbling fluidized bed [texte imprimé] / Miloslav Hartman, Auteur ; Otakar Trnka, Auteur ; Michael Pohořelý, Auteur . - 2010 . - pp.2672–2680. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp.2672–2680 Mots-clés : Temperature  Freeboard  Fluidized  Bed Résumé : A plug flow model is presented for the oxidation of hazardous carbon monoxide into inert carbon dioxide taking place in the freeboard region above a freely bubbling fluidized reactor. The extent of the reaction in oxygen- and water vapor-bearing flue gas is described as a function of the fraction of solids ejected into the freeboard from the bed surface, the relative throughput, the gas density, and the global rate of reaction. Experimental measurements were conducted to determine the axial concentration profiles of carbon monoxide and other species throughout the freeboard. Steady-state measurements were carried out in an electrically heated reactor with an inner diameter of 9.36 cm above a gently fluidized bed of heat-resistant ceramsite particles in which a precursive liguid fuel (isopropanol) was burned. The global burnout reaction is assumed to be first order in carbon monoxide and one-half order with respect to oxygen and water vapor. The rate parameters for CO and O2 reacting in the freeboard were determined from the measured concentration profiles. The numeric solutions of the model equations outline the possibilities and limitations for the performance of an afterburner chamber. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901760f

Use of pressure fluctuations to determine online the regime of gas-solids suspensions from incipient fluidization to transport / Miloslav Hartman in Industrial & engineering chemistry research, Vol. 48 N° 14 (Juillet 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 14 (Juillet 2009) . - pp. 6830–6835 Titre : Use of pressure fluctuations to determine online the regime of gas-solids suspensions from incipient fluidization to transport Type de document : texte imprimé Auteurs : Miloslav Hartman, Auteur ; Otakar Trnka, Auteur ; Karel Svoboda, Auteur Année de publication : 2009 Article en page(s) : pp. 6830–6835 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Gas-solids  suspensions  Pressure  fluctuating  signal  Fluidization Résumé : A novel quantity, based on the concept of symmetry of the sampled pressure fluctuating signal, is developed and incorporated into our extended fluctuation model of fluidized gas−solid suspensions. The new measure of the signal symmetry makes it possible to define the transition from the final bubbling regime to the onset of turbulence in the bed. Experimental measurements were performed in a transparent glass, 6-m-tall column with an inner diameter (i.d.) of 0.08 m. Three different kinds of solids were employed in the experiments: ceramsite (particle size 1.0−1.25 mm; group D particles; spoutable particles), glass beads (particle size 0.8−1.00 mm; group D particles), and high-calcium, coarse-grained limestone (particle size 0.50−0.65 mm; group B powder; sandlike particles). It was discovered that also the different bubbling regimes and the starting point of dilute (entrainment) regimes can be identified with the aid of the proposed method. The development of the diluted beds is considerably influenced by the architecture and configuration of the top of the fluidization column. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900055x [article] Use of pressure fluctuations to determine online the regime of gas-solids suspensions from incipient fluidization to transport [texte imprimé] / Miloslav Hartman, Auteur ; Otakar Trnka, Auteur ; Karel Svoboda, Auteur . - 2009 . - pp. 6830–6835. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 14 (Juillet 2009) . - pp. 6830–6835 Mots-clés : Gas-solids  suspensions  Pressure  fluctuating  signal  Fluidization Résumé : A novel quantity, based on the concept of symmetry of the sampled pressure fluctuating signal, is developed and incorporated into our extended fluctuation model of fluidized gas−solid suspensions. The new measure of the signal symmetry makes it possible to define the transition from the final bubbling regime to the onset of turbulence in the bed. Experimental measurements were performed in a transparent glass, 6-m-tall column with an inner diameter (i.d.) of 0.08 m. Three different kinds of solids were employed in the experiments: ceramsite (particle size 1.0−1.25 mm; group D particles; spoutable particles), glass beads (particle size 0.8−1.00 mm; group D particles), and high-calcium, coarse-grained limestone (particle size 0.50−0.65 mm; group B powder; sandlike particles). It was discovered that also the different bubbling regimes and the starting point of dilute (entrainment) regimes can be identified with the aid of the proposed method. The development of the diluted beds is considerably influenced by the architecture and configuration of the top of the fluidization column. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900055x