Teaching Experiences in Chemical Engineering: Design, Manufacturing and Start-up of a Lab-scale Distillation Unit using Problem-based Learning

Se ha propuesto y puesto en práctica una nueva metodología de aprendizaje basado en problemas en una asignatura de carácter experimental en la carrera de ingeniería química en la Escuela Técnica Superior de Ingeniería de la Universidad de Sevilla (España). La metodología se basa en el trabajo con grupos reducidos y aprendizaje basado en problemas, proponiendo nuevos desafíos y oportunidades para el desarrollo de competencias de alumnos de ingeniería. Los alumnos han desarrollado tareas de diseño de procesos, selección de alternativas, toma de decisiones, diseño de ingeniería básica y gestión de compras, que han culminado con el montaje y puesta en marcha de una unidad de destilación a escala laboratorio. La metodología ha permitido trabajar todas las competencias adscritas a la asignatura con un alto grado de participación y motivación del alumnado. Por lo tanto, se considera una herramienta atractiva y útil para su incorporación en asignaturas de experimentación en ingeniería química.A new problem solving methodology is proposed for a course which is essentially experimental for student of chemical engineer at the Higher Technical Engineering School of the University of Seville in Spain is proposed. The methodology is based on small group work and problem-based learning, proposing new challenges and opportunities to develop skills and competencies in engineering student. The students developed tasks regarding process design, selection of optimal alternative, decision making, basic engineering design and purchase management, which concluded with the assembly and starting-up of a laboratory scales distillation unit. The methodology allowed working all subject competences with high participation and motivation from the students. Therefore, it is considered to be a useful and attractive tool to be incorporated to experimental chemical engineering courses.Departamento de Ingeniería Química y AmbientalInstituto de Ciencias de la Educación de la Universidad de Sevill

K-Promoted Ni-Based Catalysts for Gas-Phase CO2 Conversion: Catalysts Design and Process Modelling Validation

The exponential growth of greenhouse gas emissions and their associated climate change problems have motivated the development of strategies to reduce CO2 levels via CO2 capture and conversion. Reverse water gas shift (RWGS) reaction has been targeted as a promising pathway to convert CO2 into syngas which is the primary reactive in several reactions to obtain high-value chemicals. Among the different catalysts reported for RWGS, the nickel-based catalyst has been proposed as an alternative to the expensive noble metal catalyst. However, Ni-based catalysts tend to be less active in RWGS reaction conditions due to preference to CO2 methanation reaction and to the sintering and coke formation. Due to this, the aim of this work is to study the effect of the potassium (K) in Ni/CeO2 catalyst seeking the optimal catalyst for low-temperature RWGS reaction. We synthesised Ni-based catalyst with different amounts of K:Ni ratio (0.5:10, 1: 10, and 2:10) and fully characterised using different physicochemical techniques where was observed the modification on the surface characteristics as a function of the amount of K. Furthermore, it was observed an improvement in the CO selectivity at a lower temperature as a result of the K-Ni-support interactions but also a decrease on the CO2 conversion. The 1K catalyst presented the best compromise between CO2 conversion, suppression of CO2 methanation and enhancing CO selectivity. Finally, the experimental results were contrasted with the trends obtained from the thermodynamics process modelling observing that the result follows in good agreement with the modelling trends giving evidence of the promising behaviour of the designed catalysts in CO2 highscale units.Ministerio de Ciencia e Innovación PID2019-108502RJ-I00 IJC2019-040560-IMinisterio de Ciencia e Innovación RYC2018-024387-

Solvents for Carbon Dioxide Capture

Anthropogenic CO2 emissions are considered the major contributor of greenhouse gas emissions worldwide. The mitigation of this kind of CO2 emissions relies on a portfolio of alternatives where CO2 absorption appears as the nearest approach to be applied at industrial scale. Researchers have been focused on developing new formulations of solvents to make more competitive CO2 absorption as a carbon capture and storage (CCS) technology. In this sense, this chapter summarizes both the conventional solvents and the most recent investigations on this field. Chemical absorption is more suitable for a lot of industrial process due to the flue gas conditions: ambient pressure, low CO2 concentration and large volume. Therefore numerous novel solvents came up in recent years and they are further discussed in this chapter. The most recent solvents, their mechanisms and kinetics and the advantages and disadvantages are also included. Finally, physical solvents are adequate in high CO2 partial pressure applications and they are reported in the last section. Although physical absorption field is constrained to high-pressure flue gas, physical solvents provided higher performance in CO2 separation process and their characteristics are also summarized.Ministerio de Economía y Competitividad OXYSOLVENT Pro. CTM-2014-58573-RFondo Europeo de Desarrollo Regiona

Estimación de la recarga natural a los acuíferos del Norte de Gran Canaria a partir del balance de cloruros

La zona Norte de Gran Canaria se considera la de mayor recarga del acuífero insular debido a que en ella se producen los mayores registros pluviométricos de la isla y que en superficie se sitúan los materiales más jóvenes y permeables y los suelos menos retentivos, con vegetación de moderada densidad. Dentro del proyecto REDESAC se han instalado a diferentes cotas 10 colectores abiertos de agua de lluvia para muestrear mensualmente la deposición seca y húmeda. A partir de estos datos y la estimación de la concentración de cloruros del agua de recarga se ha aplicado el método del balance de cloruro para evaluar la recarga natural. Los resultados revelan que la recarga media multianual estimada supone aproximadamente un 30% de la precipitación y se incrementa al aumentar la altitud. Esto supone un incremento sobre las estimaciones previas, aunque aún está en discusión el efecto de la escorrentía superficial.The northern part of Gran Canaria is considered the largest source of aquifer recharge in the island. It is due to the greatest rainfall records of the island are located in this zone, the surface materials are younger and permeable, and the soils are less retentive, with vegetation of moderate density. Within the project REDESAC 10 open rainwater collectors were installed at different heights to sample monthly bulk (dry+wet). From these data and the estimation of the chloride concentration of recharge water, the chloride balance method was applied for evaluating natural recharge. The results show that the multi-year average recharge estimation represents approximately 30% of precipitation and increases with increasing altitude. This means an increase over previous estimates, although the effect of surface runoff is still under discussion.Universidad Nacional de La Plat

Techno-Economic Comparison of Integration Options for an Oxygen Transport Membrane Unit into a Coal Oxy-Fired Circulating Fluidized Bed Power Plant

The inclusion of membrane-based oxygen-fired combustion in power plants is considered an emerging technology that could reduce carbon emissions in a more efficient way than cryogenic oxygen-fired processes. In this paper, a techno-economic assessment was developed for a 863 MWₑₗ,ₙₑₜ power plant to demonstrate whether this CCS technique results in a reduction in efficiency losses and economic demand. Four configurations based on oxygen transport membranes were considered, while the benchmark cases were the air combustion process without CO₂ capture and a cryogenic oxygen-fired process. The type of driving force through the membrane (3-end or 4-end), the point of integration into the oxy-fuel combustion process, the heating system, and the pollutant control system were aspects considered in this work. In comparison, the efficiency losses for membrane-based alternatives were lower than those in the cryogenic oxygen-fired process, reaching savings of up to 14% net efficiency. Regarding the specific energy consumption for CO₂ capture, the configuration based on the oxygen transport membrane unit with 4-end mode and hot filtration presented 1.01 kWₑₗ,ₙₑₜ,·h/kgCO₂ captured with 100% CO₂ recovery, which is an improvement of 11% compared with the cases using cryogenic oxygen. Comparing economic aspects, the specific investment costs for cases based on the oxygen transport membrane unit varied between 2520 and 2942 $/kWₑₗ,ₙₑₜ·h. This was between 39.6 and 48.2% above the investment for the reference case without carbon capture. However, its hypothetical implantation could suppose a savings of 10.7% in terms of investment cost compared with cryogenic oxygen-based case. In terms of the levelized cost of electricity and the cost of CO₂ avoidance, the oxygen transport membrane configurations achieved more favorable results compared with the cryogenic route, reaching savings up to 14 and 38%, respectively. Although oxygen transport membrane units are currently not mature for commercial-scale applications, the results indicated that its application within carbon capture and storage technologies can be strongly competitive

Soil and Water Management Factors That Affect Plant Uptake of Pharmaceuticals: A Case Study

Water and food security are of global concern. Improving knowledge on crops’ potential uptake of pharmaceutical compounds (PhCs) is necessary to guarantee consumer health and improve the public’s perception of reclaimed water reuse. This study aimed to determine how water management (bottom-up applied for being supplied by Subsurface Drip Irrigation) and the plant rhizosphere effect on the uptake of PhCs. Five PhCs were mixed: atenolol, carbamazepine, dicoflenac, ibuprofen and valsartan. A total of 5 treatments were considered: 3 concentrations of PhCs in agricultural volcanic soil: 0.1, 10 and 100 µg·L−1; 0.1 µg·L−1 in sterilized soil; and a blank with three plant replications at 30, 45, and 60 days after emerging. The maximum quantity of the added PhCs was 100 µg·kg soil−1. A variant of the QuEChERS method was followed to extract PhCs from samples. The limits of quantification were between 10 ng·L−1 and 100 ng·L−1 in extracts. No PhCs over the limits of detection were detected (0.06–0.6 µg·kg−1 of dry plant sample). Hence, the described water reuse methodology poses a negligible consumer risk, which contrasts with hydroponic systems in which this risk has been shown. The results are discussed in terms of the effects of irrigation system, water management and the soil-plant barrier

Occurrence of Pharmaceutical Compounds in Groundwater from the Gran Canaria Island (Spain)

The presence of pharmaceutical compounds in the whole environment is a growing concern. These compounds might be present in the effluents of wastewater treatment plants and, hence, irrigation with treated sewage may be a source of groundwater pollution. The volcanic aquifer that lies NE of Gran Canaria (Spain) was studied to address the relationship of the occurrence of pharmaceutical compounds and a golf course that has been irrigated with regenerated water since 1973. Of the 14 analyzed groundwater samples, five wells were chosen to perform annual monitoring. Irrigation water and soil leachate were also evaluated. The target analytes were atenolol, metamizole, fluoxetine, ibuprofen, nicotine, permethrin, caffeine, and their metabolite paraxanthine. The environmental risk is limited as the concentrations of the pharmaceuticals measured in the sampled wells were always below 60 ng·L−1 (lower than the detected caffeine and nicotine concentrations). Wide variations for the same wells were measured among sampling campaigns, and also among the different wells. The study points to the importance of sample conservation during transport and the need to perform analyses immediately, or to follow an in-situ extraction procedure to carry concentrated samples under better conditions

Occurrence of Pharmaceutical Compounds in Groundwater from the Gran Canaria Island (Spain)

The presence of pharmaceutical compounds in the whole environment is a growing concern. These compounds might be present in the effluents of wastewater treatment plants and, hence, irrigation with treated sewage may be a source of groundwater pollution. The volcanic aquifer that lies NE of Gran Canaria (Spain) was studied to address the relationship of the occurrence of pharmaceutical compounds and a golf course that has been irrigated with regenerated water since 1973. Of the 14 analyzed groundwater samples, five wells were chosen to perform annual monitoring. Irrigation water and soil leachate were also evaluated. The target analytes were atenolol, metamizole, fluoxetine, ibuprofen, nicotine, permethrin, caffeine, and their metabolite paraxanthine. The environmental risk is limited as the concentrations of the pharmaceuticals measured in the sampled wells were always below 60 ng·L−1 (lower than the detected caffeine and nicotine concentrations). Wide variations for the same wells were measured among sampling campaigns, and also among the different wells. The study points to the importance of sample conservation during transport and the need to perform analyses immediately, or to follow an in-situ extraction procedure to carry concentrated samples under better conditions

Aplicación de las TIC como apoyo al proceso de enseñanza-aprendizaje de los procesos psicológicos básicos en asignaturas de primer y segundo ciclo de la Universidad de Alicante

Los materiales que se presentan a continuación están elaborados por la Red Tecnológica de Innovación Educativa "Aplicación de las TIC como apoyo al proceso de enseñanza-aprendizaje de los procesos psicológicos básicos en asignaturas de primer y segundo ciclo de la Universidad de Alicante". La idea del presente proyecto surge de la necesidad de generar herramientas de trabajo, adaptadas a las nuevas tecnologías de la información y la comunicación, que nos ayuden a promover la docencia de calidad en nuestras asignaturas.Vicerrectorado de Tecnología e Innovación Educativa de la Universidad de Alicant