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This study aimed to evaluate the potential of microalgae grown in wastewater to recover carotenoids and biogas in a biorefinery approach. To this end, two pilot raceway ponds treating real wastewater were operated with a hydraulic retention time (HRT) of 8 and 6 days. The maximum total carotenoid content in harvested biomass was 4.3 mg·gDW-1 with a HRT of 8 days, while it stabilized at 1.5–2.2 mg·gDW-1 with a HRT of 6 days. Biochemical methane potential tests were then run to quantify the biogas production from carotenoid-extracted biomass (136.3 mLCH4·gVS-1), which corresponded to 86% of the methane yield achievable from raw microalgal biomass. Co-digestion with primary sludge increased the methane yield production both for raw and carotenoid-extracted biomass by 58 and 86%, respectively, when a 75:25 ratio was employed and by 28 and 44%, respectively, when a 50:50 ratio (VS basis) was used. This approach is promising for recovering resources (bio-based products and bioenergy) in the framework of a circular bioeconomy. This research has received funding from MCIN/AEI/10.13039/501100011033 and “ERDF A way of making Europe’’ under the projects AL4BIO (RTI2018-099495-B-C21) and Cyan2Bio (PID2021-126564OB-C32). E. Ruales acknowledges her grant 2020 FISDUR 00592 funded by AGAUR (Generalitat de Catalunya). M. Bellver acknowledges her grant PRE2019-091552 funded by MCIN/AEI/ 10.13039/501100011033 and “ESF Investing in your future”.

Abstract The sustainability of the built environment largely depends on its energy and environmental performances. The overall objective, across the different phases of the building life cycle, is to improve building and system performances in terms of economics, comfort, environmental impact and durability. Several modelling methodologies have been developed in order to evaluate the energy performance of buildings. Generally, every modelling methodology responds effectively to some specific tasks, but there exists a lack of integration in particular with respect to the cross-disciplinary role of data. Given the multi-scale and multi-objective nature of the problem of optimization of the energy and environmental performances of the built environment, an appropriate synthesis and integration process in modelling methodologies has to be identified, addressing realistically the uncertainties inherently present in modelling strategies. Visualization and data analysis techniques are successfully used in a wide variety of applications, both in theoretical and applied domains, but questions remains about their robustness, efficiency and applicability to the problems introduced before. The paper aims to analyze critically these topics by means of case studies, showing a possible path to create a multi-scale methodology able to synthesize all the relevant aspects.

ABSTRACTDifferent tourism development models have different implications in terms of their economic, social and environmental impact. This article analyses the sustainability of tourism development...

AbstractIntroductionFoetal alcohol spectrum disorders (FASD) are a set of preventable conditions where the foetus is exposed to alcohol in utero and as a result suffers adverse consequences. To develop a public health strategy related to FASD, it is important to first establish what is known by the public about this condition. This study aimed to assess the current level of knowledge about FASD in the UK general population.MethodsA mixed methodology study was conducted using a 17‐item questionnaire and focus group sessions. Four focus groups were held with an average of 10 people in each group. Semi‐structured questions and thematic analysis of interviews alongside quantitative analysis of the questionnaire data was completed. The research was approved by an National Health service (NHS) research ethical committee.ResultsA total of 674 people responded to the questionnaire and a majority (86.7%) had heard about FASD, with most receiving their information from the media (26.2%) or from their work (27.7%). Four broad themes emerged. Overall these were: a general lack of knowledge about the subject; information about the subject needed to be personally relevant; there was a need for further education; and there was a lack of clarity in the current guidance on alcohol use in pregnancy.Discussion and conclusionsCurrently there appears to be a superficial level of knowledge about FASD in the UK general public. More detailed work in subgroups, such as young women, to identify their specific needs may be necessary before targeted public health and educational interventions can be developed to meet the needs of the general public.

The deployment of a wireless sensor and actuator network (WSAN) in IoT applications is a complex task. The need to establish the number of nodes, sensors and actuators, as well as their location and characteristics, requires a tool that allows preliminary determination of these data. In addition, because of the IoT scenarios where present a large number of sensors and actuators, it is necessary to analyze the scalability of these systems. This article proposes the study of the scalability of IoT Applications by means of simulation techniques. The Ptolemy II simulation tool and a real MQTT message broker were used. The authors present a case study related to the deployment of networks of sensors and actuators as an integral part of an IoT application to monitor and control the parks of a city. Experimental results demonstrate that the use of simulation techniques allow to analyze the scalability of this t ype o f applications.

Thermophilic co-digestion of sewage sludge with three different doses of trapped grease waste (GW) from the pre-treatment of a WWTP has been assessed in a CSTR bench-scale reactor. After adding 12% and 27% of grease waste (on COD basis), the organic loading rate increased from 2.2 to 2.3 and 2.8 kgCOD m-3 d-1 respectively, and the methane yield increased 1.2 and 2.2 times. Further GW increase (37% on COD basis) resulted in an unstable methane yield and in long chain fatty acids (LCFA) accumulation. Although this inestability, the presence of volatile fatty acids in the effluent was negligible, showing good adaptation to fats of the thermophilic biomass. Nevertheless, the presence of LCFA in the effluent worsens its dewatering properties. Specific methanogenic activity tests showed that the addition of grease waste ameliorates the acetoclastic activity in detriment of the hydrogenotrophic activity, and suggests that the tolerance to LCFA can be further enhanced by slowly increasing the addition of lipidrich materials.

Artículos en revistas A new multistage and stochastic mathematical model of an integrated distribution system planning problem is described in Part I. The efficiency and validity of this model are tested by carrying out a case study on a standard IEEE 41-bus radial distribution system. The numerical results show that the simultaneous integration of energy storage systems (ESSs) and reactive power sources largely enables a substantially increased penetration of variable generation (wind and solar) in the system, and consequently, reduces overall system costs and network losses. For the system, a combined wind and solar PV power of up to nearly three times the base-case peak load is installed over a three-year planning horizon. In addition, the proposed planning approach also considerably defers network expansion and/or reinforcement needs. Generally, it is clearly demonstrated in an innovative way that the joint planning of distributed generation, reactive power sources, and ESSs, brings significant improvements to the system such as reduction of losses, electricity cost, and emissions as a result of increased renewable energy sources (RESs) penetration. Besides, the proposed modeling framework considerably improves the voltage profile in the system, which is crucial for a normal operation of the system as a whole. Finally, the novel planning model proposed can be considered as a major leap forward toward developing controllable grids, which support large-scale integration of RESs info:eu-repo/semantics/publishedVersion

The increasing effects of climate change and extreme weather events on the operation of power systems highlight the need for developing effective techniques and models for evaluating the challenges that power systems may have to deal with in the future for maintaining high levels of resilience. Within this context, the aim of the `Resilient Electricity Networks for Great Britain (RESNET)' project is to develop and demonstrate a comprehensive approach to analyse the effects of climate-related changes on the resilience of the Great Britain's electricity system, and to develop tools for quantifying the value of adaptation measures that would enhance its resilience. This paper presents an overview of the key research activities and findings of RESNET project, specifically addressing possible climate change implications related to demand and supply scenarios, component ratings, and impact of extreme weather on system reliability. The final aim is to provide insights on various climate and weather-related challenges that the Great Britain's electricity system might face in the future.