• Energy Research
• 12. Responsible consumption close
• Spanish National Research Council close

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Abstract Fuel staging is a common alternative for flame stabilization in the vicinity of the lean blowout limit in gas turbine combustors. Whereas this technique has been normally applied to stabilize very lean flames, fuel staging could also have some effect at richer conditions, due to the modification of the spatial distribution of fuel-air ratio, even for a constant global equivalence ratio. This could bring some benefits in syngas flames, where flashback and instabilities may become the main operating issues. However, no previous reference on the effects of fuel staging on those phenomena has been found in published works. The main objective of this work was, therefore, studying the impact and potential benefits of fuel staging with regard to two important syngas combustion issues: widening the stability range of syngas flames and reducing (or, if possible, avoiding) flashback-induced instabilities. At the same time, the effect on pollutant emissions was determined, with a view to minimize their increase or even to attempt to achieve further reduction. In addition, the influence of the injector geometry was also analyzed by comparing the results of different configurations. The results revealed that, if the secondary injector was properly designed, a small quantity of secondary fuel could be enough for avoiding flashback, at the same time that the pressure fluctuations, in case of flashback-induced instabilities, were almost totally removed without significantly increasing pollutant emissions. This finding could be exploited for practical applications, as fuel staging strategies could be useful to alleviate the operational problems due to syngas burning in lean premixed combustors.

Surplus of glycerol due to the increase of biodiesel production has become an economic drawback for the development of biofuel itself. In this work, we show that it is possible to take advantage of glycerol for the synthesis of derivatives such as ketals, which can be used in biodiesel blends. The synthesis of ketals has been successfully carried out in good yields by using a cheap and reusable catalyst, K10 montmorillonite. The analysis of biodiesel blends quality parameters revealed the improvement of their cold properties, but some parameters such as fatty acid methyl ester (FAME) content and oxidation stability do not reached EN14214 specifications. In order to overcome this issue, esterification of the free hydroxyl group has been carried out leading to products with improved and promising properties for biodiesel blends. The authors acknowledge Entaban Biocombustibles del Pirineo (Project OTRI 2009), MICINN (Projects Consolider Ingenio 2010 CSD 2006-0003 and CTQ2008-05138) and DGA (grant of M. De Torres). Peer reviewed

The paper elaborates an empirical study on the relation between trade competitiveness and energy policy based on a bilateral gravity model applied to a panel of 19 EU countries over the period 1990–2015. We focus on harmonisation of domestic policies and on the speed of convergence towards low-carbon energy targets. By explicitly connecting international trade with innovation and economic competitiveness, we fill a gap in the literature on the sustainable energy transition. Our analysis yields three main findings. First, bilateral policy alignment matters for trade performance. Second, the more balanced and comprehensive the domestic policy mix, the higher the export capacity. Third, countries at the frontier of the EU transition process gain market shares at the expense of those lagging behind. We are grateful to the editor in chief and three anonymous referees for constructive comments. DC acknowledges financial support of Ministerio Ciencia e Innovación (Ref. PID2020-119096RB-I00/MCIN/AEI/10.13039/501100011033). Ministero dell'Istruzione e dell'Università The usual caveat applies.

Populations of Moina micrura and Brachionus rubens in a deep waste treatment pond were exposed to the natural short-term fluctuations of unionised ammonia (90-min intervals of monitoring) that occur in the course of a day during a summer algal bloom. Under natural conditions, three replicate experiments were conducted in which water temperature, pH, dissolved oxygen, total ammonia, unionised ammonia, phytoplankton biomass and zooplankton (number of living and dead organisms, mortality rate and instant mortality) were studied. The time-course of unionised ammonia concentration was consistent with those shown by temperature, pH, phytoplankton biomass, dissolved oxygen, Moina micrura mortality and Brachionus rubens mortality. On the other hand, temperature, pH and dissolved oxygen never exceeded the tolerance ranges described for Moina and Brachionus, which led us to attribute the cause of zooplankton mortality to unionised ammonia toxicity. Mortality rates of 63%, 27% and 34% were recorded for Moina in each replicate experiment. Brachionus was less affected, with mortalities of 7.3%, 6.2% and 6.0%. These results confirm previous field observations (Water Res. 34(14) (2000) 3666; Water Res. 37(5) (2003) 1048) that attributed a reduction in zooplankton biomass during certain periods of summer (algal blooms) to a harmful side-effect of an excessive increase in phytoplankton biomass: high photosynthetic activity during these periods of proliferation of algae gives rise to an increased pH (>/=8) and, subsequently, leads to production of unionised ammonia (toxic for aquatic organisms) from its ionised fraction.

9 figures, 2 tables. Chemical looping with oxygen uncoupling (CLOU) process, involves the use of two interconnected fluidized bed reactors, where oxygen carrier particles are able to release O2 at the fuel reactor operation conditions. Cu-based oxygen carriers containing a kaolin-reinforced MnFe mixed oxide as magnetic support, were prepared by granulation to improve their oxygen carrier properties by means of a simplified preparation method. A study was performed into the effect of kaolin concentration and calcination temperature on magnetic permeability, crushing strength, attrition, agglomeration resistance, and reactivity. Two oxygen carriers containing 28.5 wt% CuO-5 wt% kaolin and 30 wt% CuO-7.5 wt% kaolin, respectively, and both calcined at 1100 °C, were selected because they maintained their magnetic properties and reactivity after kaolin addition and showed improvement in their mechanical resistance. They were tested in a batch fluidized bed reactor (BFBR) to evaluate their fluidization behaviour. Low attrition rate without any agglomeration phenomena was observed for both of oxygen carriers up to temperature of 950 °C. The material prepared with 7.5 wt% kaolin demonstrated improved mechanical resistance, very low attrition rate and higher CuO utilization for the CLOU process after use in the BFBR, while maintaining reactivity during redox cycles and magnetic properties without agglomeration problems. This work was supported by the SWINELOOP project, Grant PID2019-106441RB-I00 funded by MICIN/AEI/http://dx.doi.org/10.13039/501100011033, the Gobierno de Aragón – Dpto. de Ciencia, Universidad y Sociedad del Conocimiento - Project LMP166_21, and the Spanish Research Council (CSIC) through the Intramural Project (201980E043). I. Adánez-Rubio acknowledges for “Juan de la Cierva” Program (Grant IJC2019-038987-I funded by MCIN/AEI/http://dx.doi.org/10.13039/501100011033). A. Filsouf thanks Combustión y Gasificación T05_20R for the funding received. Peer reviewed

The Miño is the most important river in the NW Iberian Peninsula. When it flows through Ourense town (Spain), the attractiveness of the thermal springs hides the importance of the fluvial potholes developed over bedrock. These forms reflect the strength of erosion processes, linked to fluvial incision over time. Potholes have an environmental, didactic, socio-economic and cultural potential. In order to promote their integration within territorial heritage, this research is focused on a place-based knowledge and practice. This study aimed to define the meanings and interests of fluvial potholes, regarding their sustainable uses as georesources and offering fit information for the key social actors to assist territorial development. An inventory of sculpted forms was carried out in an urban reach of the Miño River. After the site diagnosis and form characterisation, a set of fluvial potholes (82 cases) was identified within the thermal area. The assessment of the geomorphological and use/management interests delivered their values as resources for territorial sustainability. Ten potholes, selected from a preliminary list and identified through the methodology, have a potential for education, leisure and recreation. Actions designed to raise awareness of the interests and values of these geodiversity components are also presented. Xunta de Galicia | Ref. ED481A-2015/410 Universidade de Vigo | Ref. INOU15-02 G501 Deputación de Ourense | Ref. INOU15-02 G501

A novel method for sewage sludge treatment based on subjecting the wet sludge to high temperature thermal treatment in a microwave is being investigated at INCAR. Under the appropriate operating conditions, drying, pyrolysis and gasification of the sewage sludge take place, giving rise to a gas with a high CO and H2 content and an oil with a low PAH content. Moreover, due to the high temperatures that can be attained during the process it is possible to obtain a solid residue which is partially vitrified. Unlike other methods aimed at maximizing the porous texture of the solid residue in order to produce adsorbents, the aim of the method proposed in this work is to obtain a solid residue with minimal porous textural development, where the heavy metals present in the residue are occluded in a glassy-like matrix. The advantages of this technique are a substantial volume reduction with respect to the initial sludge and a solid residue that is more resistant to the leaching of organic substances and heavy metals than the char obtained by conventional pyrolysis.