11 research outputs found

    The biomass based electricity generation potential of the Province of Cienfuegos, Cuba

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    By 2013, the province of Cienfuegos in Cuba consumed about 5165 GWh of primary energy, of which an estimated 60 % was used to produce 767 GWh of electricity. 29 % of the primary energy was obtained from renewable fuel, and only less than 5 % of the biomass energy, was used to produce about 27 GWh of biomass based electricity. This study proposes and assesses opportunities to produce electricity from biomass in the sugar industry of the province. The scenarios considered include: upgrading the agricultural yield of sugarcane, producing energy cane and combusting it after the sugarcane milling season, combusting the filter cake, combusting marabu (Dichrostachys cinerea, a bush tree considered a plague in Cuba) after the sugarcane milling season, and updating the electricity generation technology. Results are given for the different scenarios and it is shown that a combined scenario, including upgrading agricultural yield of sugarcane, upgrading electricity generation technology, combusting filter cake, and producing energy cane to generate electricity after the sugarcane milling season, thus allowing to use the generation units in sugar factories during 8000 h per year affords a potential production of 1150 GWh of electricity, 50 % more than consumed in Cienfuegos province in 2013. © 2016, Springer Science+Business Media Dordrecht

    Metal release from contaminated estuarine sediment under pH changes in the marine environment

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    The contaminant release from estuarine sediment due to pH changes was investigated using a modified CEN/TS 14429 pH-dependence leaching test. The test is performed in the range of pH values of 0-14 using deionised water and seawater as leaching solutions. The experimental conditions mimic different circumstances of the marine environment due to the global acidification, carbon dioxide (CO2) leakages from carbon capture and sequestration technologies, and accidental chemical spills in seawater. Leaching test results using seawater as leaching solution show a better neutralisation capacity giving slightly lower metal leaching concentrations than when using deionised water. The contaminated sediment shows a low base-neutralisation capacity (BNCpH 12 = -0.44 eq/kg for deionised water and BNCpH 12 = -1.38 eq/kg for seawater) but a high acid-neutralisation capacity when using deionised water (ANCpH 4 = 3.58 eq/ kg) and seawater (ANCpH 4 = 3.97 eq/kg). Experimental results are modelled with the Visual MINTEQ geochemical software to predict metal release from sediment using both leaching liquids. Surface adsorption to iron- and aluminium- (hydr)oxides was applied for all studied elements. The consideration of the metal-organic matter binding through the NICA-Donnan model and Stockholm Humic Model for lead and copper, respectively, improves the former metal release prediction. Modelled curves can be useful for the environmental impact assessment of seawater acidification due to its match with the experimental values.This work was supported by the Spanish Ministry of Economy and Competitiveness, Project No. CTM 2011-28437-C02-01, ERDF included. M. C. Martı´n-Torre was funded by the Spanish Ministry of Economy and Competitiveness by means of FPI. Fellowship No. BES-2012-053816

    Persistent cAMP-Signals Triggered by Internalized G-Protein–Coupled Receptors

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    Real-time monitoring of G-protein-coupled receptor (GPCR) signaling in native cells suggests that the receptor for thyroid stimulating hormone remains active after internalization, challenging the current model for GPCR signaling

    Datos que respaldan la evaluación de la electricidad basada en biomasa y la reducción de emisiones de ghg en Cuba

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    Assessing the biomass based electricity potential of developing nations like Cuba can help to reduce the fossil fuels dependency and the greenhouse gas emissions. The data included in this study present the evolution of electricity production and greenhouse gas emissions in Cuba. Additionally, the potentialities to produce biomass based electricity by using the most significant biomass sources in Cuba are estimated. Furthermore, estimations of the potential reductions of greenhouse gas emissions, resulting from implementing the biomass based electricity potential of the different sources discussed in the study, are included. Results point to the most promising biomass sources for electricity generation and their potential to reduce GHG emissionsEvaluar el potencial eléctrico de biomasa basado en el desarrollo Naciones como Cuba pueden ayudar a reducir la dependencia de los combustibles fósiles. y las emisiones de gases de efecto invernadero. Los datos incluidos en este estudio. Presentar la evolución de la producción de electricidad y gases de efecto invernadero. Emisiones en cuba. Además, las potencialidades para producir electricidad basada en biomasa utilizando la biomasa más significativa Se estiman fuentes en cuba. Además, las estimaciones de la reducciones potenciales de las emisiones de gases de efecto invernadero, Se incluye la implementación del potencial eléctrico basado en biomasa de las diferentes fuentes discutidas en el estudio. Los resultados apuntan a Las fuentes de biomasa más prometedoras para la generación de electricidad y Su potencial para reducir las emisiones de GEI

    Interacción universidad-industria en la producción más limpia. El caso del centro de producción más limpia en la universidad de cienfuegos en cuba, un país en transición.

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    Universities are key stakeholders in teaching, researching and supporting the implementation of cleaner production activities. This case study discusses the experience of establishing and operating the Cleaner Production Center at the University of Cienfuegos (Cuba). Establishing, starting-up and running the center during its first four years of activity was supported by two projects targeted to inter-university cooperation. The collaboration allowed to establish a master program on cleaner production which acts as a bridge between the university, and the production industry and the services sector in the province of Cienfuegos. Currently 32 students from the first two promotions graduated and the program of two other promotions is ongoing. The master thesis research works are defined improving the environmental performance of the companies or organizations the student originate from. This results in a measurable improvement of the air and surface water quality in Cienfuegos city. An estimated yearly reduction of the emission of 60,000 ton of carbon dioxide equivalents and of 400 MWh at a cement plant have been realized. Research activities currently target the pollution inventory of Cienfuegos, energy production from local biomass, and establishing indicators for sustainable development for Cienfuegos. The inter-university collaboration resulted in several publications in international peer reviewed journals. The successful inter-university North–South collaboration between Cuba and Belgium, targeted at capacity building, transfer of experience and expertise, proved to be most crucial during these first years the center was active. It allowed generating the necessary funds which are often difficult to raise in developing countries. Therefore this is a unique case of building academic experience on cleaner production.Las universidades son partes interesadas clave en la enseñanza, la investigación y el apoyo a la implementación de actividades de producción más limpia. Este estudio de caso analiza la experiencia de establecer y operar el Centro de Producción más Limpia en la Universidad de Cienfuegos (Cuba). El establecimiento, la puesta en marcha y el funcionamiento del centro durante sus primeros cuatro años de actividad se apoyaron en dos proyectos orientados a la cooperación interuniversitaria. La colaboración permitió establecer un programa maestro sobre producción más limpia que actúa como un puente entre la universidad, la industria de producción y el sector de servicios en la provincia de Cienfuegos. Actualmente, 32 estudiantes de las dos primeras promociones se graduaron y el programa de otras dos promociones está en curso. Los trabajos de investigación de tesis de maestría se definen mejorando el desempeño ambiental de las compañías u organizaciones de las que se originan los estudiantes. Esto resulta en una mejora medible de la calidad del aire y del agua superficial en la ciudad de Cienfuegos. Se ha realizado una reducción anual estimada de la emisión de 60,000 toneladas de equivalentes de dióxido de carbono y de 400 MWh en una planta de cemento. Las actividades de investigación apuntan actualmente al inventario de contaminación de Cienfuegos, la producción de energía a partir de biomasa local y el establecimiento de indicadores para el desarrollo sostenible de Cienfuegos. La colaboración interuniversitaria dio lugar a varias publicaciones en revistas internacionales revisadas por pares. La exitosa colaboración interuniversitaria Norte-Sur entre Cuba y Bélgica, enfocada en el desarrollo de capacidades, la transferencia de experiencia y experiencia, demostró ser crucial durante estos primeros años en que el centro estuvo activo. Permitió generar los fondos necesarios que a menudo son difíciles de recaudar en los países en desarrollo. Por lo tanto, este es un caso único de construcción de experiencia académica en producción más limpia

    Herramientas para mejorar la previsión y control del consumo eléctrico en hoteles

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    Hotels are among the most energy intensive tourism facilities. To monitor and control the monthly and yearly energy consumption in hotels, different indicators have been proposed. These indicators, developed on yearly or annual basis, do not permit rapid detection and mitigation of malpractices and overconsumptions in hotel facilities. Moreover, these indicators do not consider the influence of physical parameters such as outdoor temperature, or, when they do, rather complex coefficients are used, precluding implementation in hotel facilities. This study discusses the use of Energy Performance Indicators to assess and control the electricity consumption in hotels. To this end a new indicator considering the outdoor temperature is introduced. Based on this indicator daily control graphs are developed, allowing a more rapid detection of overconsumptions and malpractices towards a higher electricity efficiency. One advantage of this approach is that no investments are required to implement it. The tools were implemented in two Cuban hotels of different characteristics, where reductions of the electricity consumption in 2014 compared to 2013 of 10 and 11%, were achieved.Los hoteles se encuentran entre las instalaciones turísticas más intensivas en energía. Para monitorear y controlar el consumo de energía mensual y anual en hoteles, se han propuesto diferentes indicadores. Estos indicadores, desarrollados en forma anual o anual, no permiten una rápida detección y mitigación de malas prácticas y excesos de consumo en las instalaciones del hotel. Además, estos indicadores no consideran la influencia de parámetros físicos como la temperatura exterior o, cuando lo hacen, se utilizan coeficientes más bien complejos, lo que excluye la implementación en las instalaciones del hotel. Este estudio analiza el uso de indicadores de rendimiento energético para evaluar y controlar el consumo de electricidad en los hoteles. Para ello se introduce un nuevo indicador considerando la temperatura exterior. Sobre la base de este indicador, se desarrollan gráficos de control diario, que permiten una detección más rápida de los excesos de consumo y las malas prácticas hacia una mayor eficiencia de la electricidad. Una ventaja de este enfoque es que no se requieren inversiones para implementarlo. Las herramientas se implementaron en dos hoteles cubanos de diferentes características, donde se lograron reducciones en el consumo de electricidad en 2014 en comparación con 2013 de 10 y 11%

    DGT-measured fluxes explain the chloride-enhanced cadmium uptake by plants at low but not at high Cd supply

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    The technique of diffusive gradients in thin films (DGT) has been shown to be a promising tool to assess metal uptake by plants in a wide range of soils. With the DGT technique, diffusion fluxes of trace metals through a diffusion layer towards a resin layer are measured. The DGT technique therefore mimics the metal uptake by plants if uptake is limited by diffusion of the free ion to the plant roots, which may not be the case at high metal supply. This study addresses the capability of DGT to predict cadmium (Cd) uptake by plants at varying Cd supply. To test the performance of DGT in such conditions, we used the chloride (Cl-) enhancement effect, i.e. the increase in Cd solution concentrations-due to chloride complexation of Cd-and Cd uptake with increasing Cl- concentrations, as previously characterized in pot, field and solution culture experiments. The uptake of Cd by spinach was assessed in soil amended with Cd (0.4-10.5 mg Cd kg-1) and NaCl (up to 120 mM) in a factorial design. Treatments with NaNO3 were included as a reference to correct for ionic strengths effects. The effect of Cl- on the shoot Cd concentrations was significant at background Cd but diminished with increasing soil Cd. Increasing Cl- concentrations increased the root area based Cd uptake fluxes by more than a factor of 5 at low soil Cd, but had no significant effect at high soil Cd. Short-term uptake of Cd in spinach from nutrient solutions confirmed these trends. In contrast, increasing Cl - concentrations increased the DGT measured fluxes by a factor of 5 at all Cd levels. As a result, DGT fluxes were able to explain soil Cl - effects on plant Cd concentrations at low but not at high Cd supply. This example illustrates under which conditions DGT mimics trace metal bioavailability. If biouptake is controlled by diffusive limitations, DGT should be a successful tool for predicting ion uptake across different conditions. © 2008 Springer Science+Business Media B.V.Carla Oporto, Erik Smolders, Fien Degryse, Liesbeth Verheyen, Carlo Vandecasteel
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