Calcium-Looping performance of mechanically modified Al2O3-CaO composites for energy storage and CO2 capture

This work reports the Calcium-Looping (CaL) multicycle performance under energy storage and CO2 capture conditions of different Al-composites prepared by milling mixtures of nanoalumina and natural limestone powders. The micro- and nanostructure of the composites have been analyzed by X-ray diffraction, scanning electron microscopy and high-resolution transmission electron microscopy as affected by the type of CaL conditions employed, either for energy storage in Concentrated Solar Power (CSP) plants or for post-combustion CO2 capture. Two types of calcium aluminates are formed under these diverse CaL conditions. A calcium aluminate with ratio Ca/Al 1) under CaL-CO2 capture conditions presumably due to the higher calcination temperature, which withdraws from the sorbent a relatively higher amount of active Ca. Moreover, the addition of nano-alumina, and the consequent generation of calcium aluminate, affects in a diverse way the microstructure and morphology of the CaO particles as depending on the CaL application, which critically modifies the performance of the composites.Ministerio de Economia y Competitividad CTQ2014-52763-C2, CTQ2017-83602-C

Low-cost Ca-based composites synthesized by biotemplate method for thermochemical energy storage of concentrated solar power

An ever more environmentally conscious society demands the use of green, sustainable and high-efficiency renewable energy resources. However, large-scale energy storage remains a challenge for a deep penetration of power produced from renewables into the grid. The Calcium-Looping (CaL) process, based on the reversible carbonation/calcination of CaO, is a promising technology for thermochemical energy storage (TCES) in Concentrated Solar Power (CSP) plants. Natural limestone to be used as CaO precursor is cheap, non-toxic and abundant. Nevertheless, recent works have shown that carbonation of CaO derived limestone at optimum conditions for TCES is limited by pore-plugging, which leads to severe deactivation for large enough particles to be employed in practice. In our work, we have synthesized inexpensive CaO/SiO2 composites by means of a biotemplate method using rice husk as support. The morphological and compositional features of the biomorphic materials synthesized help improve the CaO multicycle activity under optimum CSP storage conditions and for particles sufficiently large to be managed in practical processes.Ministerio de Economía y Competitividad CTQ2014-52763-C2, CTQ2017-83602-C

Spatiotemporal evolution of U and Th isotopes in a mine effluent highly polluted by Acid Mine Drainage (AMD)

The spatiotemporal evolution of both U and Th isotopes in a mine effluent highly polluted by acid mine drainage (AMD) was evaluated. The acidic tributary, which born from the outflows of an abandoned sulfide mine, flows into the Odiel River. AMD comprises an important source of natural radionuclides, presenting concentrations of 238U and 232Th, two and four orders of magnitude higher, respectively, than the background values of surface continental waters. These natural radionuclides behave conservatively along the mine effluent (pH < 2.5) throughout the hydrological year. Under AMD conditions uranium is in the hexavalent state U(VI) and the main dissolved species are uranyl sulfate complexes. The polluted tributary has a significant impact on the Odiel River acidifying its waters during the low flow season and increasing up to one order of magnitude the activity concentrations of U and Th isotopes. U presented a conservative behavior in the Odiel River during the low flow season (pH ≈ 3), however it is removed from the liquid phase in the wet season (pH ≈ 6), probably due its coprecipitation/adsorption onto Al-phases. Th shows a high sensitivity to small increases of pH, and it is strongly coprecipitated/adsorbed with or onto Fe-oxyhydroxydizes in the river.This research was funded by the University of Huelva and the Operative FEDER Program-Andalucía 2014–2020 (UHU-1255876, UHU-202020); The European Regional Development Fund through the Agencia Estatal de Investigaci´on (research grant PID2020–116461RBC21 and 116461RA-C22), and the Andalusian government (I+D+i- JAPAIDI-Retos project PY20_00096). Jos´e Luis Guerrero thank the Spanish Ministry of Universities for the Margarita Salas research grant. Funding for open access charge: Universidad de Huelva / CBUA

A Review of the Commercial Uses of Sulphate Minerals from the Titanium Dioxide Pigment Industry: The Case of Huelva (Spain)

This study was focused on the historical evolution of the waste management policy carried out by the Spanish industry devoted to titanium dioxide pigments manufacturing for minimising its environmental impact. This challenge was achieved by modifying the original chemical process and converting the originally dissolved sulphate and sulphuric acid present in the final streams of the factory into sulphate minerals (melanterite FeSO4 7H2O, szomolnokite FeSO4 H2O, and gypsum CaSO4 2H2O). These by-products were physicochemically, mineralogically and radiologically characterised in order to gain basic information for its subsequent commercial use. Some of the uses summarised in this study for both ferrous sulphates are as a supplier of iron to prevent chlorosis, animal food, manufacture of cement (to reduce Cr VI), primary flocculants for ferrous sulphates, magnetite nanoparticle and nano-Fe2O3 formation, production of magnetite concentrate, remediation of polluted soils with metals, and treatment of wastewaters. Red gypsum was analysed as a substitute for natural gypsum in the manufacture of cement, construction materials, inhibitor in soil erosion, and the immobilisation of heavy metals in agricultural soils and carbonation processes.This research was partially supported by the Spanish Government Department of Science and Technology (MINECO) through the project "Fluxes of Radionuclides Emitted by the Phosphogypsum Piles Located at Huelva; Assessment of the Dispersion, Radiological Risks and Remediation Proposals" (Ref. CTM, 2015-68628-R)), the Regional Government of Andalusia project called "Basic processes regulating the fractionations and enrichments of natural radionuclides under acid mine drainage conditions" (Ref.: UHU-1255876), and the University of Cadiz project called "New methodogy of radioisotope isolation with environmental interest for its measurement by alpha spectrometry" (Ref: PR2019-024). Documen

Metabarcoding data of prokaryotes and eukaryotes inhabiting the phosphogypsum stockpiles on the salt marshes of Huelva (SW Spain)

Artículo científico de metadatos bioinformáticosAround 100 Mt of phosphogypsum (PG) of extreme acidity and with high concentrations of heavy metals and radionuclides have been deposited on the salt marshes of the Tinto River estuary in Huelva (SW Spain) for more than forty years. The microbial community able to thrive in these adverse conditions remains totally unknown, despite the fact that it can highly influence the biogeochemical cycle of the phospho- gypsum components and include new species with biotechnological interest. High throughput sequencing of 16S/18S rRNA encoding genes is a potent tool to uncover the microbial diversity of extreme environments. This data article de- scribes for the first time the prokaryotic and eukaryotic diversity of two water samples collected in the Huelva phosphogypsum stacks. The raw amplicons of the 16S/18S rRNA maker genes for the two phosphogypsum samples and two reference samples (seawater and the Tinto River water) obtained after sequencing on MiSeq platform are provided. The operational taxonomic units (OTUs) obtained after the treatment and clustering of the obtained reads with the QIIME2 pipeline and their taxonomic assignation performed by comparison with the SILVA database are also presented to complete the information of the article “Exploring the microbial community inhabiting the phosphogypsum stacks of Huelva (SW, Spain) by a high throughput 16S/18S rDNA Sequencing approach”.Funding for open access charge: Universidad de Huelva / CBUAThe authors thank Fertiberia S.A. for its support in obtaining the water samples used in this study. P. Gómez-Villegas acknowledges the financial support of the University of Huelva (EPIT 2016–17). This research was funded by University of Huelva and the Operative FEDER Program- Andalucía 2014-2020 (UHU-1257518 and UHU-1255876); The SUBV. COOP.ALENTEJO-ALGARVE- ANDALUCIA 2021; The European Regional Development Fund through the Agencia Estatal de In- vestigación (research grant PID 2019–110438RB-C22) and the Andalucian government (I + D + i- JA-PAIDI-Retos project 2020- PY20_00728)Funding for open access charge: Universidad de Huelva / CBU

High-performance and low-cost macroporous calcium oxide based materials for thermochemical energy storage in concentrated solar power plants

High energy density, cycling stability, low cost and scalability are the main features required for thermochemical energy storage systems to achieve a feasible integration in Concentrating Solar Power plants (CSP). While no system has been found to fully satisfy all these requirements, the reversible CaO/CaCO3 carbonation reaction (CaL) is one of the most promising since CaO natural precursors are affordable and earth-abundant. However, CaO particles progressively deactivate due to sintering-induced morphological changes during repeated carbonation and calcinations cycles. In this work, we have prepared acicular calcium and magnesium acetate precursors using a simple, cost-effective and easily scalable technique that requires just the natural minerals and acetic acid, thereby avoiding expensive reactants and environmentally unfriendly solvents. Upon thermal decomposition, these precursors yield a stable porous structure comprised of well dispersed MgO nanoparticles coating the CaO/CaCO3 grains that is resistant to pore-plugging and sintering while at the same time exhibits high long term effective conversion. Process simulations show that the employment of these materials could significantly improve the overall CSP-CaL efficiency at the industrial level.Ministerio de Economía y Competitividad CTQ2014-52763-C2, CTQ2017-83602-C

Sanitation network sulfide modeling as a tool for asset management. The case of the city of Murcia (Spain)

Hydrogen sulfide (H2S) generated in sewer networks induces corrosion which today constitutes the main cause of deterioration of concrete pipes. Information regarding the H2S concentration inside sewer networks, as well as its control and reduction, has become one of the most important concerns in sanitation systems management nowadays. Modeling sulfide dynamics is the key to understanding corrosion processes. A dynamic model (called EMU-SANETSUL) was developed to calculate the H2S concentration in both the water and the gas phases of the main sewers of the city of Murcia (Spain). The model was calibrated with data from field measurements taken from both the gas phase and wastewater. Samples were taken in the network from 2016 to 2019. The model achieved an accuracy index and error index in the ranges of 57% and 15%, respectively. Empirical equations of reaction are used, and calibration parameters are detailed. The code uses an explicit discretization technique, named the Discrete Volume Element Method (DVEM). A map with the annual average concentration of H2S at the gas phase inside each pipe of the simulated network is presented. Values are compared with the mechanical deterioration inventory from closed-circuit television (CCTV) inspections performed by the Municipal Sanitation Company of the city of Murcia (EMUASA). Mechanical deterioration of pipes has diverse causes, including corrosion of pipes by H2S. Sections with high H2S concentrations that match with mechanical wear can be considered susceptible to being prioritized when rehabilitation works are being planned. Therefore, H2S concentration modeling provides valuable information for asset management of the sewer network.This research was funded by the Municipal Sanitation Company of the city of Murcia (EMUASA), grant numbers 4904/17IC-C and 5397/18IC-C from 2016 to 2019 for the Study of preventive and corrective measures to be applied in the sewerage network to minimize corrosion in the concrete pipes of the sewerage network of the city of Murcia by the action of hydrogen sulfide

El Conjunto Mínimo Básico de Datos como herramienta de vigilancia epidemiológica de la Incidencia Diabetes Mellitus 1: Experiencia en Extremadura.

The 'gold standard' of knowledge of the epidemiological evolution of the diseases that require hospitalization for diagnosis are the medical records, although the data collection is slow, difficult and time consuming, so if another faster, easier and cheaper source of data was validated, it would be very useful for epidemiological studies. Objectives. To verify The Minimum Basic Data (CMBD) validity as a source of epidemiological vigilance, comparing the CMBD data to the collected information in the medical record. Methodology. The CMBD data compared with the records of the medical records of incident cases of type 1 diabetes mellitus (DM 1) in the population under 15 years of Extremadura during 2003-2007 in a retrospective observational study and descriptive with capture-recapture method. Results. The cases were selected from 208. In 2.40% of cases, the results do not coincide with diabetes coding. 6.73% of cases, the results in the CMBD are coded with other types of diabetes or other pathology. 20.75% of the coded cases as DM 1 in with ketoacidosis doesn´t have ketoacidosis in its history, and 69.71% the medical history matches with the CMBD. Discussion. Despite of its limitations, the CMBD has proved to be a valuable source of information. Conclusion. The CMBD serves as a source of information, but not as DM 1 in epidemiological surveillanceEl 'gold standard' del conocimiento de la evolución epidemiológica de las patologías que para su diagnóstico necesitan hospitalización, son las historias clínicas, aunque la recogida de datos de ella es lenta, dificultosa y costosa en tiempo, por lo que si validáramos otra fuente de datos que fuese más rápida, fácil y barata sería de gran utilidad para los estudios epidemiológicos. Objetivos. Verificar la validez del el Conjunto Mínimo Básico de Datos (CMBD) como fuente de vigilancia epidemiológica, comparando los datos del CMBD y los recogidos en la historia clínica. Metodología. Comparamos los datos CMBD con los registros de las historias clínicas de los casos de incidencias de la DM 1 en la población menor de 15 años de Extremadura durante 2003-2007 en un estudio observacional retrospectivo y descriptivo, con método de captura-recaptura. Resultados. Los casos seleccionados fueron de 208. En el 2,40 % de los casos no coincide con la codificación de diabetes. En un 6,73 % de los casos en el CMBD están codificados con otros tipos de diabetes u otra patología. De los codificados como DM 1 con cetoacidosis, el 20,75 % no consta cetoacidosis en la historia, y en el 69,71 % coinciden historia y el CMBD. Discusión a pesar de sus limitaciones, el CMBD ha demostrado ser una fuente de información valiosa. Conclusión El CMBD sirve como fuente de información, pero no como vigilancia de la epidemiológica DM 1

Recomendaciones del Grupo GARIN para el manejo de pacientes no críticos con diabetes o hiperglucemia de estrés y nutrición artificial

Background & aims: By means of this update, the GARIN working group aims to define its position regarding the treatment of patients with diabetes or stress hyperglycaemia and artificial nutrition. In this area there are many aspects of uncertainty, especially in non-critically ill patients. Methods: Bibliographical review, and specific questions in advance were discussed and answered at a meeting in the form of conclusions. Results: We propose a definition of stress hyperglycaemia. The indications and access routes for artificial nutrition are no different in patients with diabetes/stress hyperglycaemia than in non-diabetics. The objective must be to keep pre-prandial blood glucose levels between 100 and 140 mg/dl and post-prandial levels between 140 and 180 mg/dl. Hyperglycemia can be prevented through systematic monitoring of capillary glycaemias and adequately calculate energy-protein needs. We recommend using enteral formulas designed for patients with diabetes (high monounsaturated fat) to facilitate metabolic control. The best drug treatment for treating hyperglycaemia/diabetes in hospitalised patients is insulin and we make recommendations for adapt the theoretical insulin action to the nutrition infusion regimen. We also addressed recommendations for future investigation. Conclusions: This recommendations about artificial nutrition in patients with diabetes or stress hyperglycaemia can add value to clinical work.Introducción y objetivos: En el tratamiento de los pacientes con diabetes o hiperglucemia de estrés y la nutrición artificial existen muchas áreas de incertidumbre, sobre todo en pacientes no críticos. El grupo de trabajo GARIN tiene como objetivo definir su posición en este campo. Material y métodos: Revisión bibliográfica previa y reunión presencial en la que se discutieron y contestaron preguntas específicas sobre el tema. Resultados: Proponemos una definición de hiperglucemia de estrés. Las indicaciones y las rutas de acceso a la nutrición artificial no difieren en los pacientes con hiperglucemia de estrés o diabetes respecto a los no diabéticos. El objetivo debe ser mantener los niveles de glucemia preprandial entre 100 y 140 mg/dl y postprandial entre 140 y 180 mg/dl. La hiperglucemia puede prevenirse a través de una monitorización sistemática de las glucemias capilares y un cálculo adecuado de las necesidades energético-proteicas. Recomendamos el uso de fórmulas enterales diseñadas para pacientes con diabetes (alto contenido en grasas monoinsaturadas) para facilitar el control metabólico. El mejor tratamiento farmacológico para tratar la hiperglucemia/diabetes en pacientes hospitalizados es la insulina, aconsejando adaptar la acción teórica de la insulina al régimen de infusión de la nutrición. También realizamos recomendaciones para investigaciones futuras. Conclusiones: Estas recomendaciones aportan respuestas concretas sobre cuestiones comunes en la asistencia a pacientes con diabetes o hiperglucemia de estrés y nutrición artificial