Artículos (Ingeniería Química y Ambiental)
URI permanente para esta colecciónhttps://hdl.handle.net/11441/11382
Examinar
Envíos recientes
Artículo Low-emission hydrogen supply chain for oil refining: Assessment of large-scale production via electrolysis and gasification(Elsevier, 2025-01) Romero Piñeiro, Laura; Villanueva Perales, Ángel Luis; García Haro, Pedro; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Ministerio de Ciencia e Innovación (MICIN). España; Agencia Estatal de Investigación. España; European Union; Universidad de Sevilla. TEP135: Ingeniería Ambiental y de ProcesosThe refining industry is a major hydrogen consumer, mainly relying on fossil fuel-derived hydrogen. While recent literature has focused on the production of hydrogen from water electrolysis, (waste) biomass gasification is another effective method for low-emission hydrogen production, and the refining industry is well positioned for its rapid adoption. This study conducts a techno-economic assessment of the whole supply chain of hydrogen for oil refining and analyses the LCA-climate change for residual biomass gasification and water electrolysis pathways. The potential economic and environmental benefits of combining both production methods are also analyzed. A real case study featuring four different scenarios, using data from a refinery, coupled with local data and future projections for potential curtailment and electricity prices, is included. The hourly hydrogen generation and demand profiles of the refinery were analyzed to accurately assess storage requirements. Results indicate that combining both technologies does not result in clear environmental or cost benefits, with residual biomass gasification emerging as the most advantageous configuration for the base case. Sensitivity analysis reveals that hydrogen produced via electrolysis may become more cost-effective if residual biomass prices are high enough. The importance of underground storage (salt cavern) is highlighted due to its low investment, while other storage methods can significantly increase the Levelized Cost of Hydrogen (LCOH). This study demonstrates that hydrogen production through gasification can be less carbon-intensive and more cost-competitive than electrolysis. Achieving low LCOH values and greenhouse gas emissions is feasible in all scenarios, indicating that both water electrolysis and residual biomass gasification are economically viable options for contributing to a low-emission global energy system.
Artículo FGD-Gypsum Waste to Capture CO2 and to Recycle in Building Materials: Optimal Reaction Yield and Preliminary Mechanical Properties(Multidisciplinary Digital Publishing Institute (MDPI), 2024-08) Moreno, Virginia; González Arias, Judith; Ruiz Martínez, Jaime D.; Balart-Gimeno, Rafael; Baena Moreno, Francisco Manuel; Leiva Fernández, Carlos; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Ministerio de Ciencia e Innovación (MICIN). España; Agencia Estatal de Investigación. España; European Union (UE); Universidad de Sevilla. TEP142: Ingeniería de ResiduosThe use of waste to capture CO2 has been on the rise, to reduce costs and to improve the environmental footprint. Here, a flue gas desulfurization (FGD) gypsum waste is proposed, which allows us to obtain a CaCO3-based solid, which should be recycled. The CO2 capture stage has primarily been carried out via the direct carbonation method or at high temperature. However, a high energy penalty and/or long reaction times make it unattractive from an industrial perspective. To avoid this, herein an indirect method is proposed, based on first capturing the CO2 with NaOH and later using an aqueous carbonation stage. This allows us to capture CO2 at a near-ambient temperature, improving reaction times and avoiding the energy penalty. The parameters studied were Ca2+/CO32− ratio, L/S ratio and temperature. Each of them has been optimized, with 1.25, 100 mL/g and 25 °C being the optimal values, respectively, reaching an efficiency of 72.52%. Furthermore, the utilization of the produced CaCO3 as a building material has been analyzed. The density, superficial hardness and the compressive strength of a material composed of 10 wt% of CaCO3 and 90 wt% of commercial gypsum, with a water/solid ratio of 0.5, is measured. When the waste is added, the density and the mechanical properties decreased, although the compressive strength and superficial hardness are higher than the requirements for gypsum panels. Thus, this work is promising for the carbonation of FGD-gypsum, which involves its chemical transformation into calcium carbonate through reacting it with the CO2 of flue gasses and recycling the generated wastes in construction materials.Artículo Tandem catalytic approaches for CO2 enriched Fischer-Tropsch synthesis(Elsevier B.V., 2024-05-21) Blay Roger, José Rubén; Nawaz, Muhammad Asif; Baena-Moreno, Francisco M.; Bobadilla Baladrón, Luis Francisco; Ramírez Reina, Tomás; Ramírez Reina, Tomás; Universidad de Sevilla. Departamento de Química Inorgánica; Universidad de Sevilla. Departamento de Ingeniería Química y AmbientalFischer-Tropsch Synthesis (FTS) allows the conversion of syngas to high-density liquid fuels, playing a key role in the petrochemical and global energy sectors over the last century. However, the current Global Challenges impose the need to recycle CO2 and foster green fuels, opening new opportunities to adapt traditional processes like FTS to become a key player in future bioenergy scenarios. This review discusses the implementation of CO2-rich streams and in tandem catalysis to produce sustainable fuels via the next generation of FTS. Departing from a brief revision of the past, present, and future of FTS, we analyse a disruptive approach coupling FTS to upstream and downstream processes to illustrate the advantages of process intensification in the context of biofuel production via FTS. We showcase a smart tandem catalyst design strategy addressing the challenges to gather mechanistic insights in sequential transformations of reagents in complex reaction schemes, the precise control of structure-activity parameters, catalysts aging-deactivation, optimization of reaction parameters, as well as reaction engineering aspects such as catalytic bed arrangements and non-conventional reactor configurations to enhance the overall performance. Our review analysis includes technoeconomic elements on synthetic aviation fuels as a case of study for FTS applications in the biofuel context discussing the challenges in market penetration and potential profitability of synthetic biofuels. This comprehensive overview provides a fresh angle of FTS and its enormous potential when combined with CO2 upgrading and tandem catalysis to become a front-runner technology in the transition towards a low-carbon future.Artículo Smouldering of different dry sewage sludges and residual reactivity of their intermediates(Elsevier, 2019-07) Ronda Gálvez, Alicia; Della Zassa, Micol; Gianfelice, G.; Iáñez Rodríguez, Irene; Canu, P.; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Universidad de Granada; Universidad de Sevilla. TEP135: Ingeniería Ambiental y de ProcesosThe oxidation of dry sewage sludge evolves quite differently depending on the origin of the sludge, even in the case of predominantly municipal origin. The differences are less evident by analyzing the materials with traditional techniques of thermogravimetric analysis suggesting that they derive predominantly from physical, rather than chemical features. This is clearly indicated by thermogravimetric measurements on larger samples (tens of grams), where heat- and mass transfer emerge. Several reaction phases during smouldering are very well identified, operating at sufficiently low heating rate. Mixtures of different sewage sludges average the reactivity, but analytical vs. larger samples suggest different effects on the global reactivity; it appears anticipated in differential scanning calorimetry and reduced on larger samples, presumably because of the ashes that limit the permeation of oxygen. The attenuation of the reactivity is remarkable in the oxidation of char. The ashes produced by the more reactive component, once totally burnt, limit the oxidation of char in the less reactive one, reducing the rate of oxygen transfer. At the same time, ashes provide an additional shield to heat dissipation, allowing the smouldering to progress longer. Ashes showed clear catalytic effects on small samples, but in larger samples the ashes’ prevailing effect is a physical, non-chemical process that affect the total smouldering rate, likely to control smouldering at large scale. The large gap between analytical techniques and measurements on larger samples suggests the importance to validate the conversion of unconventional solid fuels at a larger scale, where physical processes of heat- and mass transfer likely to limit the overall rate in real scale applications can be identified. We also isolated intermediate chars showing a different reactivity depending on the origin of the sludge.Artículo Elements partitioning during thermal conversion of sewage sludge(Elsevier, 2019-04) Ronda Gálvez, Alicia; Gómez Barea, Alberto; García Haro, Pedro; Ferreira de Almeida, Vanessa; Salinero González, Jesús; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Ministerio de Economia, Industria y Competitividad (MINECO). EspañaThe concentration of a high number of elements in the solid residue after the thermal conversion of dried sewage sludge was measured, mainly targeting the change in concentration of heavy metals under different thermochemical conditions. Experiments were conducted in a laboratory fluidized bed and in a packed bed reactor under conditions relevant for pyrolysis, gasification and combustion. The concentration of twenty elements in the solid residue was measured as a function of temperature, reaction time, oxidizing atmosphere (O2 and H2O), presence of Cl in the gas and type of reactor gas-solid contact (fluidized vs packed bed). The temperature and the oxidizing conditions in the gas were shown to play a dominant role, whereas the effect of reaction time was negligible. The concentrations of most of main elements increased with temperature, whereas those of most of minor elements followed the opposite trend. The presence of chlorine in the gas resulted in higher concentration of Fe, Mg, Cu, Ni, Zn Co, Sb and V in the residue, while it promoted almost complete volatilization of Pb and Sn. The concentration of minor elements in the residue was lower in packed bed than in fluidized bed, as a result of the higher dilution caused by the lower degradation of the fuel sample in packed bed conditions. The enrichment of the elements in the solid residue decreased with the temperature, being more significant in pyrolysis than in combustion and gasification.Artículo Scale effects and mechanisms ruling the onset of wastewater sludges self-heating(2019-11) Della Zassa, Micol; Ronda Gálvez, Alicia; Gianfelice, G.; Zerlottin, M.; Canu, P.; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Universidad de Granada; European Commission. Fondo Social Europeo (FSO); Ministerio de Economia, Industria y Competitividad (MINECO). España; Universidad de SevillaWe investigated the autoignition and self-heating of three different dried, wastewater treatment sludges of different origin and share of municipal and industrial waste water. We used a custom testing apparatus to study large (approx. 20 g) samples, where heat- and mass transfer limitations are purposely relevant, as in real scale applications. We tested different particle size distributions, applying heating rates between 0.1 and 6.0 °C/min. We proved that i) ignition can occur in more than one step, ii) the same solid behaves very differently by changing its particle size distribution and the applied heating rate, iii) the onset is controlled by physical processes, rather than chemical, iv) the hazard is determined (and can be controlled) by modifying the particle size, the bed structure and density. We conclude that the hazard of self-ignition and heating is largely controlled (thus manageable) by the physical properties of the solids and its packing, given that its reactivity in air is always sufficiently high, once appropriate (and common) environmental conditions are met. Consistently, the self-heating hazard assessment requires investigation at a representative scale, where physical processes have an appreciable impact. Conclusions obtained on sludges are expected to apply to any biomass, with comparable properties.Artículo The future of European universities on the path to sustainable development(Sciendo, 2024-06-01) Korzeb, Zbigniew; Alonso-Fariñas, Bernabé; Irimia Diéguez, Ana Isabel; Jiménez Naharro, Félix; Kobylińska, Urszula; Di Pietro, Filippo; Palacín Sánchez, María José; Rollnik-Sadowska, Ewa; Szpilko, Danuta; Szydło, Joanna; Torre Gallegos, Antonio de la; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Universidad de Sevilla. Departamento de Economía Financiera y Dirección de Operaciones; Polish National Agency for Academic Exchange; Universidad de Sevilla. TEP135: Ingeniería ambiental y de procesos; Universidad de Sevilla. SEJ566: Finanzas y Responsabilidad Social Corporativa; Universidad de Sevilla. SEJ500: Grupo de Investigación en Finanzas y TurismoThe article addresses the issue of the future of European universities on the path to sustainable development. The main aim of the article is to describe foreseeable future directions of the sustainable development of universities and ways to achieve Sustainable Development Goals. In effect, the authors identify weaknesses, assess threats and recommend coordinated solutions and alternatives for the sustainable development of universities. This research will contribute to future work by explaining what the future of universities will look like on their sustainability journey. The results of the Delphi study conducted with the participation of 201 experts from 47 countries allowed for the identification of factors shaping the future of universities on the path to sustainable development.Artículo Management effectiveness evaluation in protected areas of southern Ecuador(Elsevier, 2017-04-01) López-Rodríguez, Fausto; Rosado Alcarria, Daniel; Universidad de Sevilla. Departamento de Ingeniería Química y AmbientalProtected areas are home to biodiversity, habitats and ecosystem as well as a critical component of human well-being and a generator of leisure-related revenues. However, management is sometimes unsatisfactory and requires new ways of evaluation. Management effectiveness of 36 protected areas in southern Ecuador have been assessed. The protected areas belong to three categories: Heritage of Natural Areas of the Ecuadorian State (PANE), created and funded by the State, Areas of Forest and Protective Vegetation (ABVP), created but no funded by the State, and private reserves, declared and funded by private entities. Management effectiveness was evaluated by answers of managers of the protected areas to questionnaires adapted to the socio-economic and environmental characteristics of the region. Questions were classified into six elements of evaluation: context, planning, inputs, processes, outputs and outcomes as recommended by IUCN. Results were classified into four levels: unsatisfactory, slightly satisfactory, satisfactory and very satisfactory. The PANE areas and private reserves showed higher management effectiveness levels (satisfactory and very satisfactory) than ABVP areas, where slightly satisfactory and unsatisfactory levels prevailed. Resources availability was found as the main reason behind this difference. The extension, age and province of location were found irrelevant. Outputs, inputs and processes require main efforts to improve management effectiveness. Improving planning and input in the PANE areas and inputs and outcomes on ABVP areas is necessary to obtain a similar result in all areas.Artículo Comparative study of brine management technologies for desalination plants(Elsevier, 2014-03-03) Morillo Aguado, José; Usero García, José; Rosado Alcarria, Daniel; El Bakouri, Hicham; Riaza, Abel; Bernaola, Francisco-Javier; Universidad de Sevilla. Departamento de Ingeniería Química y AmbientalIn recent years, reverse osmosis (RO) has grown as an alternative to traditional potable water sources. A major disadvantage of the RO process is the huge amount of brine and its negative impact as a result of its high salinity. This brine is usually discharged to inland water bodies or to the sea and constitutes a threat to ecosystems and species, such as Posidonia oceanica in the Mediterranean Sea; thus, further research is needed for introducing environmentally friendly and economically viable management options for RO brines.This paper gives an overview of recent research as well as different technologies available at several scales to overcome the environmental problems and evaluate profitability related to discharge of RO concentrates. The treatment options have been classified into four different groups according to their final purpose: 1) technologies for reducing and eliminating brine disposal, 2) technologies for commercial salt recovery, 3) brine adaptation for industrial uses and 4) metal recovery. Solar evaporation, two-stage reverse osmosis, electrodialysis, integrated processes and brine adaptation for the chlor-alkali industry are some of the topics that this paper deals with. In the conclusion section, all of the technologies are compared emphasizing all their advantages and drawbacks, feasibility and development stage in order to provide a decision tool to select the best technology for each situation.Artículo Lithium recovery from desalination brines using specific ion-exchange resins(Elsevier, 2019-10-15) Arroyo Torralvo, Fátima; Morillo Aguado, José; Usero García, José; Rosado Alcarria, Daniel; El Bakouri, Hicham; Universidad de Sevilla. Departamento de Ingeniería Química y AmbientalThis study evaluated the possibility of recovering lithium from brines by ion-exchange procedures. Three commercial ion-exchange resins were studied: K2629, TP207 and TP208. Different tests have been carried out with artificial solutions and real brines. In addition, tests were carried out for Li elution, regeneration of the resins and reuse of the regenerated resins. Sorption kinetics of lithium retention onto the three resins were studied and experimental data fit to the pseudo-second order kinetics model. Equilibrium sorption data were analysed by the Langmuir, Freundlich, Temkin and Dubinin-Radushkevic approaches. Langmuir isotherm model best described the process. The order of retention capacity of the amendments was TP207 > K2629 > TP208. Recovering Li from brines was possible with ion exchange resins. In solutions containing only Li, the three resins studied had high retention yields (>95%). The presence of other ions in solution negatively affects the behavior of the three resins studied. Regarding desorption, yields obtained ranged 73.8% - 89.8%, reaching the highest (>80%) using 4 M HCl as eluting solution. Regenerated resins showed similar yields to those obtained when the resin is used for the first time.Artículo Environmental quality in sediments of Cadiz and Algeciras Bays based on a weight of evidence approach (southern Spanish coast)(Elsevier, 2016-09-15) Usero, José Antonio; Rosado Alcarria, Daniel; Usero García, José; Morillo Aguado, José; Universidad de Sevilla. Departamento de Ingeniería Química y AmbientalThis research applies an integrated sediment quality assessment method using a weight of evidence approach to Cadiz and Algeciras Bays (southern Spain). The method is composed of several analyses (particle size profile, aqua regia extractable metals, acid labile metals, total organic carbon, toxicity bioassay with Photobacterium phosphoreum and macrobenthic community alteration). The proposed method provides a single result, the environmental degradation index (EDI). EDI defined samples as low degraded (outer areas of both bays) and moderately degraded (Inner Bay of Cadiz Bay, the surroundings of Algeciras port and the northern part of Algeciras Bay). These samples showed the highest concentration of aqua regia extractable metals, which exceeded effects range-low (ERL) for Zn (51–176 mg/l), Cu (11–54 mg/l), As (4.3–9.5 mg/l), Hg (0.17–0.28 mg/l), Ni (23–82 mg/l), and. Cr (37–134 mg/l). They also exceeded some quality criteria for total organic carbon (4.0–6.5%) and toxicity (120–240 TU/g) and showed poor results for macrobenthic community.Artículo Assessment of heavy metals bioavailability and toxicity toward Vibrio fischeri in sediment of the Huelva estuary(Elsevier, 2016-06-01) Rosado Alcarria, Daniel; Usero García, José; Morillo Aguado, José; Universidad de Sevilla. Departamento de Ingeniería Química y AmbientalRelationship between toxicity and bioavailable metals in sediments from the Huelva estuary and its littoral of influence was analyzed. Toxicity was assessed with Microtox® bioassay using a marine luminescent bacterium: Vibrio fischeri. Bioavailable metals were considered as both, acid extractable fraction of BCR procedure and the sum of exchangeable and bound to carbonates fractions of Tessier sequential extraction. A bioavailable metals index was calculated to integrate results in a single figure. Toxicity and bioavailable metals showed a similar pattern. Higher levels were found in the estuary than in the littoral (140 TU/g). In Huelva estuary, highest levels were found in the Tinto estuary (5725 TU/g), followed by the Odiel estuary (5100 TU/g) and the Padre Santo Canal (2500 TU/g). Results in this area were well over than those in nearby estuaries. Furthermore, they are similar to or even higher than those in other polluted sediments around the world. Bioavailable metal index showed a stronger correlation with acid extractable fraction of BCR (R^2 = 0.704) than that for the sum of exchangeable and bound to carbonates fractions of Tessier (R^2 = 0.661). These results suggest that bioavailable metals are an important source of sediment toxicity in the Huelva estuary and its littoral of influence, an area with one of the highest mortality risks of Spain.Artículo Application of a new integrated sediment quality assessment method to Huelva estuary and its littoral of influence (Southwestern Spain)(Elsevier, 2015-09-15) Rosado Alcarria, Daniel; Usero García, José; Morillo Aguado, José; Universidad de Sevilla. Departamento de Ingeniería Química y AmbientalA new integrated sediment quality assessment method composed of several assays (particle size profile, total metal content, protease K extraction, total organic carbon, toxicity bioassay with Photobacterium phosphoreum and macrobenthic community alteration) that provides a single result, the environmental degradation index (EDI), has been developed. The new method was tested on the Huelva estuary (southwest of Spain), a highly polluted area where metals dissolved in the water of the Tinto and Odiel rivers precipitate after flowing through the Iberian Pyrite Belt, one of the largest metallogenic areas of massive sulphide deposits in the world. The proposed method satisfactorily was able to reflect different degrees of pollution on the environmental degradation index. Thus, EDI categorized littoral samples as slightly degraded and all the Tinto and some of the Odiel as very highly degraded, emphasizing the lower zone of the Tinto estuary as the most deeply degraded of the entire study area.Artículo Ability of 3 extraction methods (BCR, Tessier and protease K) to estimate bioavailable metals in sediments from Huelva estuary (Southwestern Spain)(Elsevier, 2016-01-15) Rosado Alcarria, Daniel; Usero García, José; Morillo Aguado, José; Universidad de Sevilla. Departamento de Ingeniería Química y AmbientalThe bioavailable fraction of metals (Zn, Cu, Cd, Mn, Pb, Ni, Fe, and Cr) in sediments of the Huelva estuary and its littoral of influence has been estimated carrying out the most popular methods of sequential extraction (BCR and Tessier) and a biomimetic approach (protease K extraction). Results were compared to enrichment factors found in Arenicola marina. The linear correlation coefficients (R^2) obtained between the fraction mobilized by the first step of the BCR sequential extraction, by the sum of the first and second steps of the Tessier sequential extraction, and by protease K, and enrichment factors in A. marina, are at their highest for protease K extraction (0.709), followed by BCR first step (0.507) and the sum of the first and second steps of Tessier (0.465). This observation suggests that protease K represents the bioavailable fraction more reliably than traditional methods (BCR and Tessier), which have a similar ability.Artículo Synergizing Carbon Capture Storage and Utilization in a Biogas Upgrading Lab-scale Plant Based on Calcium Chloride: Influence of Precipitation Parameters(Elsevier, 2019) Baena-Moreno, Francisco M.; Rodríguez Galán, Mónica; Vega Borrero, Fernando; Ramírez Reina, Tomás; Vilches Arenas, Luis Francisco; Navarrete Rubia, Benito; Universidad de Sevilla. Departamento de Química Inorgánica; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Engineering and Physical Sciences Research Council (UK); Royal Society (UK)Herein a strategy for biogas upgrading in a continuous flow absorption unit using CaCl 2 as capturing agent is reported. This process is presented as an alternative to the standard physical regeneration processes to capture carbon dioxide (CO 2 ) from biogas effluents with inherent high energy penalties. This work showcases a systematic study of the main parameters (reaction time, reaction temperature, and molar ratio reactant/precipitator) affecting calcium carbonate (CaCO 3 ) precipitation efficiency in a reaction between sodium carbonate (Na 2 CO 3 ) and CaCl 2 . In addition, the purity and main characteristics of the obtained product were carefully analysed via in a combined characterization study using Raman, XRD, and SEM. Our results indicate that acceptable precipitation efficiencies between 62 and 93% can be reached by fine tuning the studied parameters. The characterization techniques evidence pure CaCO 3 in a calcite structure. These results confirmed the technical feasibility of this alternative biogas upgrading process through CaCO 3 production.Artículo Stepping toward Efficient Microreactors for CO2 Methanation: 3D-Printed Gyroid Geometry(ACS Publications, 2021-06) Baena-Moreno, Francisco M.; González Castaño, Miriam; Navarro de Miguel, Juan Carlos; Miah, Kamal U.M.; Ossenbrink, Ralf; Odriozola Gordón, José Antonio; Arellano García, Harvey; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Universidad de Sevilla; Ministerio de Ciencia, Innovación y Universidades (MCIU). España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER); Universidad de Sevilla. TEP135: Ingeniería Ambiental y de ProcesosThis work presents a comparative study toward the development of efficient microreactors based on three-dimensional (3D)-printed structures. Thus, the study evaluates the influence of the metal substrate geometry on the performance of structured catalysts for the CO2 methanation reaction. For this purpose, the 0.5%Ru–15%Ni/MgAl2O4 catalyst is washcoated over two different micromonolithic metal substrates: a conventional parallel channel honeycomb structure and a novel 3D-printed structure with a complex gyroid geometry. The effect of metal substrate geometry is analyzed for several CO2 sources including ideal flue gas atmospheres and the presence of residual CH4 and CO in the flue gas, as well as simulated biogas sources. The advantages of the gyroid 3D complex geometries over the honeycomb structures are shown for all evaluated conditions, providing in the best-case scenario a 14% improvement in CO2 conversion. Moreover, this contribution shows that systematically tailoring geometrical features of structured catalysts becomes an effective strategy to achieve improved catalyst performances independent of the flue gas composition. By enhancing the transport processes and the gas–catalyst interactions, the employed gyroid 3D metal substrates enable boosted CO2 conversions and greater CH4 selectivity within diffusion-controlled regimes.Artículo Bio-methane and bio-methanol co-production from biogas: A profitability analysis to explore new sustainable chemical processes(Elsevier, 2020-08) Baena-Moreno, Francisco M.; Pastor Pérez, Laura; Wang, Qiang; Ramírez Reina, Tomás; Universidad de Sevilla. Departamento de Ingeniería Química y Ambiental; Universidad de Sevilla; Universidad de Sevilla. TEP135: Ingeniería Ambiental y de ProcesosHerein a potential synergy between biogas upgrading and CO2 conversion to bio-methanol is investigated. This novel idea arises as an alternative path to the traditional biogas – to – bio-methane route which involves CO2 separation. In this work a techno-economic analysis of the process was performed to study the profitability for potential investors. A total of 15 scenarios were analysed. Different biogas plant sizes were examined as baseline scenarios: 100, 250, 500, and 1000 m3/h. Furthermore the potential effect of governmental incentives through bio-methane subsidies (feed-in tariffs and investment percentage) was studied. Finally a sensitivity analysis was developed to study the effect of key parameters. The results of the baseline scenarios demonstrated that not profitable results can be obtained without subsidies. Bio-methane subsidies as feed-in tariffs proved to be effective for the 500 and 1000 m3/h plant sizes. For a feed-in tariff subsidy of 40 €/MW, 500 m3/h biogas production plants are remarkably profitable (net present value equal to 3106 k€). Concerning 1000 m3/h biogas production plants, 20 €/MW of subsidies as feed-in tariffs gives similar net present value result. Our results point out that only big biogas production can produce bio-methanol at profitable margins under 90–100% of investment subsidied. The sensitivity analysis showed that electricity, natural gas and bio-methanol price can affect considerably to the overall profitability, converting predicted positive cases in negative scenariosArtículo Efecto de la adición de nanosílice en las propiedades mecánicas de un hormigón de muy alta resistencia(Sociedad Española de Integridad Estructural. Grupo español de Fractura, 2023) Ríos Jiménez, José David; Leiva Fernández, Carlos; Cifuentes-Bulté, Héctor; 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). EspañaEl objetivo de este trabajo es analizar el efecto que la adición de nano-sílice, mezclado en solución líquida durante el proceso de amasado, provoca en las propiedades mecánicas de un hormigón de muy alta resistencia. Para ello, se analizaron diferentes mezclas, todas ellas con la misma composición inicial y diferentes porcentajes de nano-sílice (0,1,5; 2,5; 3,5; 5 y 7,5%). Se redujo el contenido de cemento, ya que cuando se añade nano-sílice en una cuantía mayor, la capacidad de autocompactación del hormigón disminuye. Los resultados mostraron una modificación de la estructura interna del material, los macroporos (entre 5 y 250 μm) disminuyen, mientras que los mesoporos con un radio medio que oscila entre 0,01 y 5 μm aumentan con la adición de nano-sílice. Las propiedades mecánicas del hormigón con nanosílice mejoraron hasta un 5% de sustitución. La energía de fractura de los hormigones no se vio afectada por la adición de nano-sílice. Por otro lado, la resistencia a la tracción aumentó ligeramente para el 1,5% de sustitución de nano-sílice.Artículo Comportamiento en fractura de un hormigón de muy alta resistencia con refuerzo multiescala(Sociedad Española de Integridad Estructural. Grupo español de Fractura, 2023) Ríos Jiménez, José David; Leiva Fernández, Carlos; Cifuentes-Bulté, Héctor; 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). EspañaEl uso del hormigón para fabricar torres de aerogeneradores es una de las aplicaciones estudiadas recientemente. Estas estructuras tubulares están expuestas a cargas cíclicas alternas. Este trabajo estudia el efecto de la adición de diferentes tipos de microfibras de carbono sobre el comportamiento en fractura de un hormigón de muy alta resistencia. Se han realizado ensayos experimentales sobre probetas prismáticas entalladas utilizando tres tipos de microfibras de carbono y diferentes contenidos (0-20 kg/m3). Todas las fibras tienen el mismo diámetro (7 μm) y diferentes longitudes (0,1, 3 y 6 mm). La resistencia a tracción de las microfibras de carbono es de 4.200 MPa, lo que reduce significativamente la probabilidad del mecanismo de fallo por rotura de la fibra. Los resultados mostraron que el uso de fibras de 6 mm con 20 kg/m3 permitieron alcanzar una mayor resistencia a tracción y energía de fractura, con incrementos del 100% y 105% respectivamente, en comparación con el hormigón de control. Las fibras más largas y con mayor contenido actuaron como barreras a la propagación de las grietas de manera más efectiva, pero la distribución de estas en la matriz fue menos uniforme y aumentó la dispersión de los resultados.Artículo Behavior of High-Strength Polypropylene Fiber-Reinforced Self-Compacting Concrete Exposed to High Temperatures(ASCE - The American Society of Civil Engineers, 2018-11-01) Ríos Jiménez, José David; Cifuentes-Bulté, Héctor; Leiva Fernández, Carlos; García Arenas, Celia; Alba, María D.; 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 (España); Universidad de Sevilla. TEP972: Mecánica de materiales y estructurasThe utilization of structural high-performance concrete reinforced with polypropylene fibers in applications demanding long exposure times to high temperatures, such as in case of thermal energy storage systems, is analyzed in this work. Different temperatures: 100, 300, 500 and 700°C (hot), as well as cooled-down states (cold) and different exposure times (6, 24 and 48 h) have been analyzed. The thermogravimetric analysis, fracture behavior, compressive strength, the Young’s modulus and tensile strength of concrete were also experimentally determined and subsequently, a comprehensive analysis of the thermal and mechanical behavior of highperformance concrete under different thermal conditions has been carried out, broadening with longer exposure times the available results about the behavior of high-performance fiber reinforced concrete subjected to high-temperatures. When the temperature is increased, the mechanical properties of this concrete diminishes. The results shown that once thermal and moisture equilibriums are reached there is no influence of the exposure time. They provide useful information about the influence of different parameters of fiber-reinforced concrete subjected to high temperatures.