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Construction involves the use of significant quantities of raw materials and entails high-energy consumption. For the sake of choosing the most appropriate solution that considers environmental and sustainable concepts, tools such as the integrated value model for sustainable assessment (Modelo Integrado de Valor para una Evaluación Sostenible, MIVES) used in Spain, plays a key role in obtaining the best solution. MIVES is a multi-criteria decision-making method based on the value function concept and the seminars delivered by experts. Such tools, in order to show how they may work, require application to case studies. In this paper, two concrete slabs manufactured with differing reinforcements during the construction of the La Canda Tunnels are compared by means of MIVES. The two concrete slabs were reinforced with a conventional steel-mesh and with polyolefin fibres. This research was focussed on the main aspects affecting the construction. That is to say, the environmental, economic, and social factors were assessed by the method, being of special impact the issues related with maintenance of the structure. The results showed that from the point of view of sustainability, the use of polyolefin fibres provided a significant advantage, mainly due to the lower maintenance required.

The ethanolic fermentation of liquid fractions (hydrolysates) issued from dilute acid pre-treatment of olive tree biomass by Pichia stipitis is reported for the first time. On the one side, P. stipitis has been reported as the most promising naturally occurring C5 fermenting microorganism; on the other side, olive tree biomass is a renewable, low cost, and lacking of alternatives agricultural residue especially abundant in Mediterranean countries. The study was performed in two steps. First, the fermentation performance of P. stipitis was evaluated on a fermentation medium also containing the main inhibitors found in these hydrolysates (acetic acid, formic acid, and furfural), as well as glucose and xylose as carbon sources. The effect of inhibitors, individually or in a mixture, on kinetic and yield parameters was calculated. In a second step, hydrolysates obtained from 1% (w/w) sulfuric acid pre-treatment of olive tree biomass at 190ºC for 10 min were used as a real fermentation medium with the same microorganism. Due to inhibition, effective fermentation required dilution of the hydrolysate and either overliming or activated charcoal treatment. Results show that ethanol yields obtained from hydrolysates, ranging from 0.35 to 0.42 g/g, are similar to those from synthetic medium, although the process proceeds at lower rates. Inhibiting compounds affect the fermentation performance in a synergistic way. Furfural is rapidly assimilated by the yeast; acetic acid and formic acid concentrations decrease slowly during the process. Activated charcoal or overliming detoxification improve the fermentability of diluted hydrolysates.

El proyecto REVen “Rehabilitación energética de viviendas sociales, aplicando productos innovadores de ventana con marcado CE” (BIA2014-56650-JIN), tiene como objetivo realizar un análisis integral del impacto de la ventana en los aspectos relativos a eficiencia energética y calidad ambiental. Para caracterizar los flujos de energía y las condiciones ambientales internas se ha construido el Laboratorio REVen. Este artículo describe la construcción y la monitorización de este laboratorio analizando los datos de su primer año de funcionamiento. Los resultados permiten afirmar que se logra una mejora significativa del confort térmico obteniendo un ahorro de energía anual del 25 %.

Considering recent environmental regulations, the need to adapt domestic biomass combustion systems to models that generate less emissions has gained relative importance. The present research proposes an analysis of the bed cooling effects on emission patterns, specifically focusing on the concentration, typology and morphological aspects of the released particles. The study was carried out by comparing the behaviour of a small-scale pilot plant with air stratification, with and without bed cooling. The results revealed an optimal behaviour of the facility with distributions of 30% primary-70% secondary air, accompanied by a significant decrease in emissions due to the reduction in the operating temperatures. More than 75% of the particles were retained in the bed on the cooled surfaces due to the effect of the prominent temperature gradient that was produced. Among the types of emitted particles (mostly with sizes below 0.1 μm), the presence of partial biomass degradation remnants was observed, representing three-quarters of the total collected matter. To a lesser extent, the presence of carbonaceous agglomerates was detected and usually in very compact clusters; however, in cases of high primary air supply, large amounts of immature soot were observed. Agencia Estatal de Investigación | Ref. RTI2018-100765-B-I00

This work evaluates, for the first time, the possibility of producing multifunctional alkali-activated composites combining ultra-low density, low thermal conductivity, high acoustic absorption, and good moisture buffering capacity. The composites were prepared using cork as a lightweight aggregate. This novel material might promote energy savings and tackle the CO2 emissions of the building sector, while simultaneously improve the comfort for inhabitants (e.g. humidity levels regulation and sound pollution reduction). The composites apparent density (as low as 168 kg/m3) and thermal conductivity (as low as 68 mW/m K) are amongst the lowest ever reported for alkali-activated materials (AAM) composites and foams, while their sound absorption ability is comparable to the best performing AAM foams reported to date, but in addition these eco-friendly composites also show good ability to passively adjust the humidity levels inside buildings. The multifunctional properties shown by the cork – AAM composites set them apart from other conventional building materials and might contribute to the global sustainability of the construction sector. Peer Reviewed

Abstract The impact of CO 2 leakage from underground storage formations on shallow water resources is a concerning aspect in CO 2 capture and storage (CCS) risk assessment. In Campo de Calatrava region (Spain), natural CO 2 fluxes from the Earth’s mantle interact with shallow aquifers, resulting in significant changes in their physical and chemical properties. The resultant water is slightly acidic (pH 5.9-6.4), oxidizing, and enriched in iron (up to 6.1×10 -4 mol·L -1 ) and other metals usually found at trace concentrations. Thermodynamic calculations reveal that aqueous Fe(III) carbonate complexes play an important role in the persistence of this high concentration of iron and trace metals in solution.