Documents disponibles écrits par cet auteur

Activation of waste tire char upon cyclic oxygen chemisorption-desorption / Francisco Heras in Industrial & engineering chemistry research, Vol. 48 N° 10 (Mai 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 10 (Mai 2009) . - pp. 4664–4670 Titre : Activation of waste tire char upon cyclic oxygen chemisorption-desorption Type de document : texte imprimé Auteurs : Francisco Heras, Auteur ; Noelia Alasino, Auteur ; Miguel A. Gilarranz, Auteur Année de publication : 2009 Article en page(s) : pp. 4664–4670 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Waste  tire  char  Chemisorption−desorption  BET  surface Résumé : Activation of waste tire char upon cyclic oxygen chemisorption−desorption permits a controlled development of porosity versus burnoff using air as feed gas for the activation process. A slow but monotonical increase of BET surface area is obtained from cycle to cycle. Initially the process led to the development of mesoporosity without generating micropores and then the micropore volume is increased whereas a decrease of narrow mesopore (20−80 nm) volume is observed, probably as a consequence of mesopore widening. Although the SBET reaches relatively low values (below 250 m2/g) even after 15 cycles, this surface development is associated with low burnoff values (around 22% for indicated BET surface area) and corresponds in an important percentage (up to about 50%) to external (nonmicropore) area. Temperatures around 210 and 550 °C for chemisorption and desorption, respectively, have been found as optimum for the purpose of preparing granular mesoporous carbons which can be interesting candidates as catalytic supports for liquid phase applications. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801764x [article] Activation of waste tire char upon cyclic oxygen chemisorption-desorption [texte imprimé] / Francisco Heras, Auteur ; Noelia Alasino, Auteur ; Miguel A. Gilarranz, Auteur . - 2009 . - pp. 4664–4670. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 10 (Mai 2009) . - pp. 4664–4670 Mots-clés : Waste  tire  char  Chemisorption−desorption  BET  surface Résumé : Activation of waste tire char upon cyclic oxygen chemisorption−desorption permits a controlled development of porosity versus burnoff using air as feed gas for the activation process. A slow but monotonical increase of BET surface area is obtained from cycle to cycle. Initially the process led to the development of mesoporosity without generating micropores and then the micropore volume is increased whereas a decrease of narrow mesopore (20−80 nm) volume is observed, probably as a consequence of mesopore widening. Although the SBET reaches relatively low values (below 250 m2/g) even after 15 cycles, this surface development is associated with low burnoff values (around 22% for indicated BET surface area) and corresponds in an important percentage (up to about 50%) to external (nonmicropore) area. Temperatures around 210 and 550 °C for chemisorption and desorption, respectively, have been found as optimum for the purpose of preparing granular mesoporous carbons which can be interesting candidates as catalytic supports for liquid phase applications. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801764x

Wastewater treatment plant synthesis and design / Noelia Alasino in Industrial & engineering chemistry research, Vol. 49 N° 18 (Septembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 18 (Septembre 2010) . - pp. 8601–8612 Titre : Wastewater treatment plant synthesis and design : combined biological nitrogen and phosphorus removal Type de document : texte imprimé Auteurs : Noelia Alasino, Auteur ; Miguel C. Mussati, Auteur ; Nicolas J. Scenna, Auteur Année de publication : 2010 Article en page(s) : pp. 8601–8612 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Wastewater  treatment Résumé : In the present work, a previous superstructure model developed for simultaneous optimization of the process configuration and equipment dimensions, i.e., optimal process synthesis and design and the operation conditions of activated sludge wastewater treatment plants, is extended to account for phosphorus as well as nitrogen removal. Along the activated sludge treatment process, the wastewater stream is exposed to different environmental conditions (anaerobic, anoxic, and aerated zones) in order to facilitate the different microbiological processes such as the release and uptake of phosphorus and the nitrification/denitrification processes. The Activated Sludge Model No. 3 extended with the Bio-P module for computing biological phosphorus removal is used to model the reaction compartments and the Takàcs model for representing the secondary settler. The performance criterion selected is the minimization of the net present value that includes investment and operating costs while verifying compliance with the effluent permitted limits. The problem is posed as a NLP problem, specifically a nonlinear programming problem with discontinuous derivatives DNLP. The optimization model is implemented and solved using a General Algebraic Modeling System, GAMS. Optimal configurations and designs obtained for several case studies are reported and discussed. The model itself and the resolution methodology prove to be robust and flexible enough to solve efficiently scenarios with a wide range of operation conditions, embedding conventional and nonconventional process configurations. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1000482 [article] Wastewater treatment plant synthesis and design : combined biological nitrogen and phosphorus removal [texte imprimé] / Noelia Alasino, Auteur ; Miguel C. Mussati, Auteur ; Nicolas J. Scenna, Auteur . - 2010 . - pp. 8601–8612. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 18 (Septembre 2010) . - pp. 8601–8612 Mots-clés : Wastewater  treatment Résumé : In the present work, a previous superstructure model developed for simultaneous optimization of the process configuration and equipment dimensions, i.e., optimal process synthesis and design and the operation conditions of activated sludge wastewater treatment plants, is extended to account for phosphorus as well as nitrogen removal. Along the activated sludge treatment process, the wastewater stream is exposed to different environmental conditions (anaerobic, anoxic, and aerated zones) in order to facilitate the different microbiological processes such as the release and uptake of phosphorus and the nitrification/denitrification processes. The Activated Sludge Model No. 3 extended with the Bio-P module for computing biological phosphorus removal is used to model the reaction compartments and the Takàcs model for representing the secondary settler. The performance criterion selected is the minimization of the net present value that includes investment and operating costs while verifying compliance with the effluent permitted limits. The problem is posed as a NLP problem, specifically a nonlinear programming problem with discontinuous derivatives DNLP. The optimization model is implemented and solved using a General Algebraic Modeling System, GAMS. Optimal configurations and designs obtained for several case studies are reported and discussed. The model itself and the resolution methodology prove to be robust and flexible enough to solve efficiently scenarios with a wide range of operation conditions, embedding conventional and nonconventional process configurations. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1000482