Ponencias (Ingeniería Química y Ambiental)

URI permanente para esta colecciónhttps://hdl.handle.net/11441/11384

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Influencia del tiempo de exposición de temperaturas en el comportamiento en fractura de hormigones autocompactantes reforzados con fibras de polipropileno
(Asociación Científico-Técnica del Hormigón Estructural (ACHE), 2017-06) Ríos Jiménez, José David; Cifuentes-Bulté, Héctor; Leiva Fernández, Carlos; Medina Encina, Fernando; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Universidad de Sevilla. Departamento de Mecánica de Medios Continuos y Teoría de Estructuras; Ministerio de Economía y Competitividad (MINECO). España
El presente estudio está centrado en el efecto de la adición de fibras de polipropileno, de diferente longitud, al comportamiento en fractura de un hormigón de alta resistencia sometido a diferentes niveles de temperatura y tiempos de exposición. La longitud de las fibras debe influir en estas propiedades, ya que se sabe que cuanto mayor es la longitud, mayor es la resistencia del hormigón reforzado frente a la rotura. Esto es de gran interés para la aplicación de este tipo de hormigones en sistemas de almacenamiento de energía termo solar. En estas aplicaciones, el hormigón es uno de los materiales de mayor interés por su capacidad térmica de almacenamiento, su trabajabilidad, disponibilidad y bajo coste.
CO2 methanation: on the modeling of reacting laminar flows in structured Ni/MgAl2O4 catalysts
(IOP Publishing, 2022) Medina Méndez, Juan A.; González Castaño, Míriam; Baena-Moreno, Francisco M.; Arellano García, Harvey; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
This work presents an overview of issues for the modeling of laminar flows in monolith catalysts. Both 0-D and 3-D models are evaluated for a parallel channel structured honeycomb catalyst (PC-HC), and a gyroid 3-D printed structured catalyst (G-3D). At the 0-D homogeneous reactor modeling level, the analysis is focused on the effect of the bulk porosity, as well as the model choice to represent Nusselt number effects. Results show the better suitability of a long tube Nusselt number model for the representation of the maximum temperature achievable in the 0-D homogeneous reactor, as well as a modest effect of the porosity on the catalyst CO2 conversion. A more detailed insight on heat transfer and the core reaction zone inside the monolith can be obtained at the 3-D homogeneous reactor modeling level.
Advanced utilisation options for biomass gasification fl y ash
(2007) Gómez Barea, Alberto; Fernández Pereira, Constantino; Vilches Arenas, Luis Francisco; Leiva Fernández, Carlos; Campoy Naranjo, Manuel; Ollero de Castro, Pedro Antonio; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
The objective of this work was to search sustainable methods for the direct utilisation of the fly ash generated in a 150 kWth fluidised-bed pilot plant using Orujillo waste, a by-product from olive oil industry. An extensive characterization was made over raw ashes generated in the process. Existing (combustion) fly ash utilisation methods were found not to be directly applicable to these gasification ashes because of the high concentrations of unburned carbon and harmful soluble compounds. Further utilisation options for management of these ashes were identified. Two utilisation paths are investigated in detail in this work: the use of ash in the manufacture of gypsum wallboards and bricks with isolation properties. These utilisation options are based on lowcost preparation methods using ash in significant proportion, yielding a considerable high-value product. They represent promising new applications with high market potential. Dedicated tests to assess these two utilisation options are issued and from this the potential application of these routes is discussed. Keyboards: gasification; pilot plant; waste disposal
Characterisation of compounds formed and added on surface of outdoor Seville City Hall
(Elsevier, 2013) Robador González, María Dolores; Arroyo Torralvo, Fátima; Pérez Rodríguez, J.L.; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Universidad de Sevilla. Departamento de Construcciones Arquitectónicas II (ETSIE)
The study of the stone surface was helpful before the restoration of the Sevilla City Hall façade. This study supplied information of the environmental factors affecting the stone and the restoration treatments used in previous interventions. The stone was thin grained carbonate constituted essentially by fragments of bioclasts and fine sand. The stone was covered by an acrylic resin. Black crust was found. Gypsum and mortars has been added to cover losses of pieces or to fix fragments of stones. A layer of lime on the surface was also detected.
Assessment of natural radioactivity levels and radiation exposure in new building materials in Spain
(Oxford University Press, 2021) Más Balbuena, José Luis; Caro Ramírez, J. R.; Hurtado Bermúdez, Santiago José; Leiva Fernández, Carlos; Universidad de Sevilla. Departamento de Física Aplicada I; Universidad de Sevilla. Departamento de Física Aplicada II; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
Novel building materials were manufactured and analyzed for 226Ra, 232Th and 40K using an HPGe gamma-ray spectrometer. The results show that the highest value of 40K was 4530 Bq per kg which was measured in a sample containing fly ashes from olive stones. The highest values of 226Ra and 232Th activities were 181 and 185 Bq per kg, which were measured in a sample with fly ashes from the co-combustion of coal and coke, respectively. On the other hand, the lowest values of 40K, 226Ra and 232Th activities were obtained for samples incorporating mussel shells. The radiological health hazard parameters, such as radium equivalent activity (Raeq), activity concentration index (I), absorbed and effective dose rates, associated with these radionuclides were evaluated. These values are within the EU recommended limits in building materials, except for samples of concrete containing fly ashes from olive stones, coal and coke. This study has contributed to the inclusion of industrial wastes that have not been collected previously in the Naturally Occurring Radioactive Material (NORM) databases on radioactivity of building materials.
Heavy metals in sediments from the Tinto River (Spain)
(1999) Usero García, José; Morillo Aguado, José; Gracia Manarillo, Ignacio; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
A complete study was carried out on metal pollution in Tinto River sediments. In the course of the study, samples were taken at 13 sites along the river and its most important tributaries, and at 4 sites in the estuary.
Tecnología de Combustibles en el Grado de Ingeniería Química
(Universidad de Sevilla, 2019) Gallego Fernández, Luz Marina; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Universidad de Sevilla. TEP135: Ingeniería Ambiental y de Procesos
El Ciclo de Mejora o CIMA se desarrolla en la asignatura Tecnología de Combustibles impartida en el Grado de Ingeniería Química de la Escuela Técnica Superior de Ingenieros. Dicho modelo se elabora con el objetivo de sustituir la forma tradicional de impartir las clases teóricas de esta asignatura, por una dinámica de trabajo más innovadora donde los alumnos cobren un mayor protagonismo en cada una de estas sesiones. La metodología de trabajo establecida se centra en el análisis de tres problemas planteados en el contexto de esta asignatura. Éstos se trabajan en grupos reducidos de alumnos partiendo de sus ideas iniciales y analizando, posteriormente, la información introducida para contrastar los resultados obtenidos. La evaluación final del ciclo refleja un gran avance en el aprendizaje de los alumnos, así como un cambio en sus aptitudes y actitudes que se ha venido manifestando durante todo el periodo de implementación del CIMA.
Approximate Prediction of Gas-Solid Conversion in Fluidized Bed Reactors
(ECI Digital Archives, 2007) Gómez Barea, Alberto; Leckner, Bob; Campoy Naranjo, Manuel; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
A simple method is proposed to evaluate the performance of fluidized bed reactors where an nth-order gas-solid reaction occurs. The method takes into account the fluid dynamics of the fluidized bed by a two-phase flow model and the rates of diffusion in the solid reactant particles (internal and external) by a simple particle model. Approximate analytical expressions are derived in terms of three effectiveness factors: interphasic, external and intraparticle. These account for the contribution of fluid-dynamic and diffusional resistances to the overall mass-transfer resistance. Gas conversion is expressed in terms of four dimensionless governing quantities and the reaction order, in this way facilitating computations. Limiting cases of the general solution are discussed by comparison with analytical solutions found in literature. The methodology can be applied to catalytic or non-catalytic systems under isothermal conditions, where one heterogeneous reaction is involved.
The Role of Biomass in the Future Development of CSP in Southern Europe: the Case of Spain
(EUBCE, 2018) García Haro, Pedro; Peñalver Pichaco, Daniel; Suárez Almeida, Montserrat; Larson, Eric; Ghoniem, Ahmed F.; Gómez Barea, Alberto; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
For 2030, Spain has set ambitious targets for increasing intermittent renewable electricity generation. Concentrated Solar Power (CSP) plants have the capability of store solar energy during operation allowing a reduction of the external support to renewable generation to cover the demand. A model has been developed for the estimation of the impact of a CSP deployment by substituting the targeted solar photovoltaic generation in the country. The results indicate that biomass can play a role in the extension of energy storage in CSP plants and providing the residual external support needed to balance the demand.
Study of the Potential Ecological Risk of Heavy Metals in the Residue from Thermal Conversion of a Sewage Sludge
(EUBCE, 2018) Ronda Gálvez, Alicia; Ferreira, V.; Salinero González, Jesús; García Haro, Pedro; Fuentes Cano, Diego Javier; Nilsson, Susanna Louise; Gómez Barea, Alberto; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
The thermal conversion of the sewage sludge by pyrolysis, gasification and combustion can be an attractive alternative because it reduces the volume of the residue and improve its properties for safe disposal. However, the high content of some heavy metals in sewage sludge has to be carefully considered to come up with rational and sustainable disposal methods. Therefore, the study of the heavy metals distribution in the final residue after the thermal conversion of the sewage sludge is a key topic in order to implement clean methods to valorize sewage sludge. Tests were performed in a horizontal fixed-bed reactor using both nitrogen (pyrolysis) and air (combustion) atmospheres at different temperatures for tests of 20 min duration. At the end of each test, the final residue was collected, and the concentration of main heavy metals was measured by ICP. The results were analyzed through various indexes to establish the enrichment of the species in different ash stream and to assess the potential ecological risk of heavy metals. Finally, obtained value were compared with existing works and standards to assess potential the application of proper management methods.
Waste Gasification for Power Generation: Assessment of Industrial and Non-Industrial Alkaline Residues as Sorbents for Acid Gas Removal
(EUBCE, 2018) García Haro, Pedro; Arroyo, J,; Almeida, V.F. de; Salinero González, Jesús; Vidal Barrero, Fernando; Gómez Barea, Alberto; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
The search of sustainable and affordable materials for the cleaning of acid gas in biomass gasification is one of the many challenges for the development of commercial gasification-based waste-to-energy plants. This study presents the potential sorbents identified in the literature. An analysis of these alkaline residues is done inspired by the Draft Specifications for the Application of UNFC to Anthropogenic Resources (UNECE/2017/SED/78). The classification is based on three categories: technical performance, societal-economic impact and environmental impact. The most interesting residue for its use in the acid gas removal of waste gasification power generation is the red mud followed by seafood shells.
Influence of the Stoichiometric Ratio on Tar Composition during Fluidized Bed Gasification
(EUBCE, 2017) Fuentes Cano, Diego Javier; Salinero González, Jesús; García Haro, Pedro; Nilsson, Susanna Louise; Gómez Barea, Alberto; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
Fluidized bed gasification is a promising technology for the energetic valorization of biomass and wastes. However the presence of heavy tars limits the use of the gas to applications where the gas is not cooled. Several parameters such as the temperature profile inside the gasifier and the gas residence time influence the concentration and composition of the tar mixture and thus the gas dew point. In autothermal air-blown fluidized bed gasifiers the stoichiometric ratio (fed air/stoichiometric air) determines the reactor temperature but the influence over the tar composition depends on the competition of the different fractions (light gas, char and tar) for the oxygen available. This paper analyzes the tar composition in the gas produced during the conversion of biomass pellets in a fluidized bed reactor when the stoichiometric ratio is raised from 0 (pyrolysis) to 0.21 (standard autothermal gasification with air). The tests were conducted at 800°C and 900°C and constant gas residence time and volatiles/carrier gas ratio. The results are discussed and compare with previous literature works, explaining some aspects of existing tar conversion models for biomass gasification.
Heavy Metals Partitioning during Thermal Conversion of Sewage Sludge in a Fluidized Bed under Conditions Relevant for Pyrolysis and Gasification
(EUBCE, 2017) Ronda Gálvez, Alicia; Ferreira, V.; Arroyo, J.; García Haro, Pedro; Fuentes Cano, Diego Javier; Nilsson, Susanna Louise; Salinero González, Jesús; Gómez Barea, Alberto; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
There is a growing concern on the final disposal of urban organic wastes, such as municipal solid waste (MSW) and sewage sludge (SS), since they constitute an available energy and material source currently not efficiently valorized. These wastes become an attractive feedstock provided proper treatment/conversion techniques are applied, dealing with their high load of impurities. The objective of this work was to investigate the partitioning of heavy metals and other relevant species during thermal treatment of sewage sludge in order to properly valorize/dispose this feedstock. Experiments were performed in a fixed-bed and a fluidized-bed reactors under conditions relevant for pyrolysis and gasification.
Dynamic assessment of Waste-to-Energy Schemes in Current European Landfill-Dominant Regions
(EUBCE, 2017) Aracil Fernández, Carmen; García Haro, Pedro; Fuentes Cano, Diego Javier; Gómez Barea, Alberto; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Universidad de Sevilla. Departamento de Ingeniería Electrónica
Even when European regulation has been encouraging landfill reduction in the last decades, 13 out of 28 EU countries still landfill more than 50% of their municipal solid waste (MSW), mainly located in Southern and Eastern Europe. In this paper, waste-to-energy (WtE) schemes based on gasification are proposed in order to minimize the landfill disposal in European landfill-dominant regions. These schemes are assessed by means of a dynamic GHG emissions methodology since comparing with a dynamic reference system (i.e. methane emissions are delayed several years after the landfilling of the wastes and the emissions continue unevenly for at least 20 years more). The evolution of current waste management system and mix of electricity production is also modeled. The results reveal that the incorporation of gasification-based WtE plants in dominated-landfill European countries has a positive climate impact compared to current waste management in the short term. The long-term climate impact is, however, not secure since it depends on the evolution of the reference system in the analyzed region. Among the assessed configurations, the fluidised bed gasifier with internal combustion engine (FBG/ICE) configuration achieves the best climate benefit since has the highest energy efficiency.
Experimental Investigation of Olive Tree Pruning Gasification in a Bench-Scale Fluidized Bed
(EUBCE, 2016) Nilsson, Susanna Louise; Gómez Barea, Alberto; Fuentes Cano, Diego Javier; Pinna, G.; García Haro, Pedro; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
Olive tree pruning was gasified in a laboratory fluidized bed reactor using air as gasifying agent. Different operating temperatures (800, 850 and 900 ºC) and equivalence ratios (ER) (0.12-0.35) were tested and additional tests were performed varying the particle size of the fuel, the biomass feed rate and the oxygen content in the air (13-40%). The composition of the product gas was determined measuring light gas components (CO2, CO, CH4, H2, C2H4, C2H2, C3, N2), tar, inorganic contaminants (NH3, HCN, H2S, HCl), and water. Solid samples collected from the cyclone and the fluidized bed were also examined. It was found that for low temperature (800 ºC) the gasification efficiency was low (0.58) due to the low char conversion. On the contrary at 900 ºC, the gasification efficiency was above 70% even for the highest ER tested (0.35). The quality of the gas was significantly improved by using O2-enriched air up to 40%.
A Tar Conversion Model for Fluidized Bed Biomass Gasifiers
(EUBCE, 2014) Fuentes Cano, Diego Javier; Gómez Barea, Alberto; Nilsson, Susanna Louise; Campoy Naranjo, Manuel; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
A comprehensive tar conversion model for biomass gasification has not been developed up to date due to the great deal of processes involved, whose stoichiometry and kinetics are not well known. Therefore, simplified schemes of reactions are assumed in existing models, reducing their capability to predict the tar composition in the gas. In this work a model to predict tar composition from wood gasification was developed. The model takes into account both tar generation from the fuel and secondary transformations of the gas in the gasifier, mainly focused on conditions applicable to fluidized beds. The model comprises a limited number of tar compounds and reactions representing the main tar species and conversion mechanisms, which stoichiometry and kinetics are based on literature data. Comparison with measurements from literature data is presented to discuss the applicability of the model.
Gasification kinetics of char from olive tree pruning with CO2 and stema in fluidized bed
(EUBCE, 2013) Nilsson, Susanna Louise; Gómez Barea, Alberto; Fuentes Cano, Diego Javier; Pardo, I.; Pinna, G.; Silva Pérez, Manuel Antonio; Ollero de Castro, Pedro Antonio; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Universidad de Sevilla. Departamento de Ingeniería Energética; CTAER (Centro Tecnológico Avanzado de Energías Renovables de Andalucía)
Kinetics of gasification of char from olive tree pruning was measured in a fluidized bed at temperatures between 760 and 900 ºC. Experiments were carried out using H2ON2 and CO2N2 mixtures to measure the rates of the gasification reactions with H2O and CO2 and to assess the inhibition effects of H2 and CO. The reaction rates with H2O were 34 times faster than those obtained with CO2 and inhibition by CO and H2 was observed to be significant, especially at low temperature. LangmuirHinshelwood kinetics was obtained for the two gasification reactions. Additional experiments were carried out with CO2H2ON2 mixture to study the simultaneous gasification with CO2 and H2O. It was found that the char was converted slightly faster in a gas mixture containing both CO2 and H2O than in a gas with the same H2O concentration but substituting CO2 by N2.
Conversion of Olive Tree Prunings Fluidized Bed: Experiments and Gasifier Modeling
(EUBCE, 2013) Nilsson, Susanna Louise; Gómez Barea, Alberto; Campoy Naranjo, Manuel; Pinna, G.; Silva Pérez, Manuel Antonio; Ollero de Castro, Pedro Antonio; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Universidad de Sevilla. Departamento de Ingeniería Energética; CTAER (Centro Tecnológico Avanzado de Energías Renovables)
Fuel conversion measurements were conducted in a laboratory fluidized bed (FB) to characterize the most important steps taking place a FB gasifier in the range of 800.900 ºC. The main inputs for the gasifier model to be developed were obtained: product yields from devolatilization (light gas, tar and char) of olive tree pruning (OTP) and gasification kinetics of the produced char with CO2 and H2O. In the second part of this work, the obtained experimental data have been employed in a previously developed FB gasifier model to assess the gasification performance with OTP under various operating conditions. The effect of equivalence ratio, temperature of the feed gas, gasifier throughput, fuel moisture and ash content were analyzed. The main outputs from the model (bed temperature, gas composition, char conversion and gasification efficiency) are used to identify the optimal operation condition
Gasification of Wastes in a Pilot Fluidized Bed Gasifier
(EUBCE, 2011) Campoy Naranjo, Manuel; Gómez Barea, Alberto; Ollero de Castro, Pedro Antonio; Nilsson, Susanna Louise; Fuentes Cano, Diego Javier; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
A technical assessment of gasification of various wastes in fluidized bed was made by conducting test in a 100 kWth pilot plant. The reactor was operated under simulated autothermal and adiabatic conditions, thus allowing scaling-up the results to industrial units. Four feed stocks were tested: orujillo, meat and bone meal, dried sewage sludge and compost from municipal solid waste. The tests were made for each fuel by changing the air ratio (stoichiometric ratio), allowing characterization of the process in terms of gas composition, gas heating value, gasification efficiency, carbon conversion and tar content. Comparison of the results with those obtained with commercial wood pellets was made. The results show that orujillo and dried sewage sludge are a potentially fuel to be gasified if carbon conversion is increased. On the other hand, gasification of meat and bone meal was found to be a process with low efficiency, despite the fuel is fully converted in the bed. Municipal solid waste is a fuel difficult to gasify because the gasification process has low efficiency and generates a great amount of ash difficult to dispose. In order to increase carbon conversion in the reactor, co-gasification of orujillo or sewage sludge with meat and bone meal is considered a promising option.
Devolatilization of two agricultural residues in fluidized bed: product distribution and influence of fluidization agent
(EUBCE, 2011) Nilsson, Susanna Louise; Gómez Barea, Alberto; Fuentes Cano, Diego Javier; Peña, Yolanda; Ollero de Castro, Pedro Antonio; Campoy Naranjo, Manuel; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental
Devolatilization of two agricultural residues; corn stover and a solid by-product from enzymatic hydrolysis of biomass (cake), was carried out in a fluidized bed at temperatures between 750 and 900 ºC. The distribution of products and composition of the light gas were determined using N2 as fluidizing gas and the effect of the fluidizing agent was studied using N2-steam and N2-CO2 mixtures. Dedicated experiments were performed in order to measure the amount of H2O formed during devolatilization and the results had good repeatability. Expressions for calculating product yields and light gas composition as a function of temperature were obtained. These expressions are useful for gasification modeling. It was found that the composition of the fluidizing gas did not have significant effect on production of light gases during devolatilization.

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